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At the Democratic Convention, a Historic Nomination

What story did the democrats tell about kamala harris and will it be enough to win.

This transcript was created using speech recognition software. While it has been reviewed by human transcribers, it may contain errors. Please review the episode audio before quoting from this transcript and email [email protected] with any questions.

[BACKGROUND CHATTER]

I’m standing in a sea of people coming out of this vast convention. And people are holding signs, smiling. There’s confetti everywhere. There are balloons, white, red, and blue. And there’s a lot of excitement.

From “The New York Times,” I’m Sabrina Tavernise. And this is “The Daily” from inside the Democratic National Convention Hall, where Kamala Harris has just accepted her party’s nomination, becoming the first woman of color in US history to do so.

Today, the story this convention told about Harris and whether that story could be enough to win.

It’s Friday, August 23.

[SERENE MUSIC]

The work and prayers of centuries have brought us to this day. What shall our our legacy be? What will our children say? Let me in my heart, when my days are through, America, America, I gave my best to you.

On night one of the Democratic National Convention, the evening was really defined by this very emotional, quite bittersweet goodbye from President Biden.

And there’s nothing we cannot do when we do it together.

God bless you all. And may God protect our troops.

It was the closing of one chapter so that another could begin. It was Kamala Harris’s moment.

[UPBEAT JAZZ MUSIC]

So right now, it’s 7:40. We are on the floor at the Democratic National Convention. It is a crazy party atmosphere, which is like a massive understatement.

Day two kicked off with delegates gathering on the convention floor, casting their votes in a kind of symbolic way to make Harris the party’s nominee.

This giant festival of lights, people in cowboy hats, people with blinking bracelets, people with Christmas lights wrapped around their hats, heads, shoulders, people wearing donkey hats. I mean, it’s very, very, very celebratory in here.

We need to see that we’re moving on. We are turning a chapter in America.

How do you feel right now?

Awesome, excitement, energized. Ready to win this election.

I love it. I love it. People are just excited, electrified, and they’re just loving it, and they’re happy.

This has been the most electrifying event I’ve ever attended in my life. It’s my first convention. But what a convention to come for, right? To make history right now, as we charge forward to November 5, to elect the first female Black president. I’m excited.

So with Harris now the nominee, a new campaign slogan appeared everywhere. And that was, “A new way forward.” But in a campaign that’s just four weeks old, it was really an open question what “a new way forward” actually meant.

We’re not going back!

We’re not going back! We’re not going back!

And then over the course of the week, as speaker after speaker took the stage, we started to get an answer. The story of forward would be told through the story of Kamala Harris herself. And the question hanging over the week was really whether that story could appeal to a broad majority of Americans, voters outside of the convention hall who will ultimately decide the election.

[UPBEAT MUSIC]

Astead, welcome to the show.

Thank you for having me.

Again. The second time in a week. And I’m very excited for it.

So Astead, we had on the show on Monday to answer a question for us, that I think a lot of people have, which is, who is Kamala Harris? And you ended that conversation by saying that the Democratic Party also recognizes this reality, that for a lot of people, she is still this unknown quantity.

And that the party had a big task here at the convention this week, which was to find a way to finally tell her story. It does seem like they’ve tried to do that. Let’s walk through the case that they’re making for her. And what you’ve seen here in your reporting for your show, “The Run-Up.”

Yeah, I mean, I think that the Democrats have definitely laid out a case for her as a candidate, but also a story for her as a person. They have leaned into the different parts of her biography to really follow through on what, I think, is the best version of her campaign, which is a little bit for everybody. There is a story there about more moderate legislation, but pieces of progressive history. There’s different parts of her bio that speak to Black communities, immigrant communities.

Of course, the historic nature of her gender and the roles like that. And I really think it has followed through on what I expected for this week, which is that she seems to function politically as a mirror of some sort, where the party wants to position her as someone who basically, no matter what you’re looking for in terms of a vessel to beat Donald Trump, you can find it in this candidate.

Let’s dig into that more. Where did the convention start, that story?

Hello, Democrats!

Yeah, I think it really starts in her personal biography.

And I’m here tonight to tell you all about the Kamala Harris that I know.

They have told a story that she often tells about her being a first generation American.

Her mother moved here from India at 19.

And being a daughter of an immigrant mother who really raised two daughters in the Bay Area from working class roots. And that’s been a real thing that they’ve tried to own.

Kamala was not born into privilege. She had to work for what she’s got.

When she was young, she worked at McDonald’s.

They talk about her working at McDonald’s in college.

And she greeted every person without thousand watt smile and said, how can I help you?

I think it’s overall about trying to present this as someone who pulled himself up by bootstraps. It represents the American dream. And I think for Democrats, it really returns them back to the place they want to be. Democrats like thinking of themselves as a party who appeals to the diversity of America, both in racial ways, in gender ways, but also in class ways.

In Kamala Harris, we have a chance to elect a president who is for the middle class because she is from the middle class.

And I think they used other parts of her identity, specifically thinking about being the first Black woman to accept a major party’s nomination.

We know folks are going to do everything they can to distort her truth.

And I think Michelle Obama’s speech, specifically, spoke to the power and anxiety that sometimes that identity can bring.

My husband and I sadly know a little something about this.

For years, Donald Trump did everything in his power to try to make people fear us. See, his limited, narrow view of the world made him feel threatened by the existence of two hard-working, highly educated, successful people who happen to be Black.

And I would also say that it was an implicit response to what Republicans and others have been trying to say, talking about Kamala Harris as a DEI hire, someone who was only in their position because of their identity. But the way that Michelle Obama framed it was that those identities have power.

I want to know. I want to know. Who’s going to tell him, who’s going to tell him that the job he’s currently seeking might just be one of those Black jobs?

Just because someone the first to be in a position, does not mean that is the only reason in the position. But it also doesn’t make those identities meaningless. The fact that she is a Black woman should be seen as a strength, not as a weakness.

Is there a risk to that, though? I mean, by openly talking about race, is there a risk that goes too far and begins to alienate voters outside the convention out in the world who they need to win in November.

I mean, there’s always a risk. But I don’t really think so. Democrats have had increasing trouble with Black voters. There’s been a downturn in Black vote share all the way dating back to 2012.

In Biden’s now suspended candidacy, that was one of the things driving his polling weaknesses was kind of tepid reception from Black voters. A pitch to them is something that is a upside of the Kamala Harris campaign. And the hope that they could consolidate that community is where any Democratic nominee needs to be as a baseline.

We both got our start as young lawyers, helping children who were abused and neglected.

One thing I noticed that came up a lot during the speeches was her background as a prosecutor. How did the party present that part of her biography?

As a prosecutor, Kamala stood up for children who had been victims of sexual abuse.

She put rapists, child molesters, and murderers behind bars.

They talk about it in the way that I think fuels what they want to say is the reason she can take on Trump, that this is someone who has stood up to bullies before, who’s not going to be intimidated easily —

And Kamala is as tough as it comes.

— who’s tough, and who doesn’t shirk away from a challenge.

And she knows the best way to deal with a coward is to take him head on, because we all know cowards are weak. And Kamala Harris can smell weakness.

I think all of that adds up to say, you can trust this person to go up against Donald Trump. You can trust this person to go up against the Republican Party, because she’s not someone who is scared.

She never runs from a fight.

A woman, a fierce woman for the people.

But then, of course, we heard about another side of Kamala Harris, a more personal side.

Yeah, and I think this is the part of Kamala Harris where I think was kind of most missing in the presidential run. Frankly, it’s the part that she keeps most private. She is a warm family member and friend.

Hello to my big, beautiful blended family up there.

And I think what the speech from her husband did was really show and lay that out.

I got married, became a dad to Cole and Ella. Unfortunately, went through a divorce, but eventually started worrying about how I would make it all work. And that’s when something unexpected happened, I ended up with Kamala Harris’s phone number.

He talks about the kind of awkwardness of their first interaction.

I got Kamala’s voicemail, and I just started rambling. “Hey, it’s Doug.”

And I think you have a real kind of sense of their genuine connection to one another.

By the way, Kamala saved that voicemail. And she makes me listen to it on every anniversary.

Like, yes, this is someone who is tough, who is taking on corporations and cartels and all of that stuff by day. But this is someone who also makes a point to cook Sunday dinner for family every week.

And she makes a mean brisket for Passover.

And makes sure to really go close to his kids and is very close with her family.

That’s Kamala. She’s always been there for our children. And I know she’ll always be there for yours, too.

Going back to the last time the Democratic Party nominated a woman, Hillary Clinton, she had presented herself in a very different way. She kind of ran away from that stuff. She was saying, I don’t bake cookies, that’s not what I do. I’m kind of out there with the men, fighting.

And this convention and this candidate, Harris, is very different. She’s a newer generation. And she can do her career and bake cookies. Those things are not in conflict. This is a different type of woman leader.

This week we talked to Senator Elizabeth Warren on “The Run-Up,” and one of the things that she mentioned was she feels that there’s been a big change from 2016, even 2020 to now. Not just the amount of women in public office, but she said they don’t have to choose between sides of themselves. And I think that’s what diversity means.

Of course, Kamala Harris can be a tough politician and also bake cookies. Hillary Clinton did that, too. It was just that she was told that was not the way that she had to present herself. What Kamala Harris is benefiting from is there’s a greater space and ability to choose multiple things at once. And so particularly if others are going to talk more directly about gender or race or other things, that kind of frees her from having the burden of doing that herself.

And in fact, Hillary Clinton, herself, did speak, of course, on day one. She talked about that glass ceiling in the history that has led to now, including her own experience in 2016.

Yeah, I thought the Hillary Clinton speech was really powerful. I think a lot of the speakers put this moment in historical context, both politically and personally.

My mother, Dorothy, was born right here in Chicago before women had the right to vote. That changed 104 years ago yesterday. And since that day, every generation has carried the torch forward. In 1972, a fearless Black congresswoman named Shirley Chisholm —

— she ran for president. In 1984, I brought my daughter to see Geraldine Ferraro, the first woman nominated for vice president. And then there was 2016, when it was the honor of my life to accept our party’s nomination for president.

The last time I was here in my hometown was to memorialize my mother, the woman who showed me the power of my own voice. My mother volunteered at the local school.

I’m the proud granddaughter of a housekeeper, Sarah Daisy, who raised her three children in a one-bedroom apartment. It was her dream to work in government, to help people.

My grandmother, the woman who helped raise me as a child, a little old white lady born in a tiny town called Peru, Kansas.

I want to talk now about somebody who’s not with us tonight. Tessie Prevost Williams was born in New Orleans not long after the Supreme Court ruled that segregated public schools were unconstitutional. That was in 1954, same year I was born. Parents pulled their kids out of the school.

There was a way that I think the candidacy and the person was placed in a long legacy, both about gender identity and racial identity that kind of teed up this Thursday as a culminating moment, both politically and I think, in a broader historical context.

Together, we put a lot of cracks in the highest, hardest glass ceiling. And you know what? On the other side of that glass ceiling is Kamala Harris raising her hand and taking the oath of office as our 47th president of the United States!

I wish my mother and Kamala’s mother could see us. They would say, keep going. Shirley and Jerry would say, keep going!

I think you can do a lot to set up a candidate to be in a good position. All of this stuff adds up to some part of the puzzle, but the biggest piece is the candidate themself. At the end of the day, they have to close the deal. And I think this moment is her chance to tell her own story in a way that sometimes she has not decided to. And that’s still what this whole convention success and failure will ride on.

We’re going to watch tonight. We’re going to watch with our colleague, Reid Epstein. And you are going to have a great episode of “The Run-Up” on Friday. We will all be tuning in.

Thank you. I appreciate you doing this, Sabrina.

Really thanks a lot, Astead.

Are you a delegate?

Sorry, we caught you mid French fry eating. What’s your feeling about Kamala and what her story has been? Are you getting to know her this week? Are there things you’ve learned about her this week?

Yeah, I’m learning more and more as we go along. The more and more I learn about her, the more I’m impressed with her. I mean, she worked at McDonald’s when she was going to college to try to pay her way through.

Her very small beginnings. Not a trust fund baby type of thing. I relate to that. Like, I was on food stamps this year. So it’s like if she can do it with that background, it gives everybody hope.

Hillary was my girl. When Hillary ran, I championed her as well. But I didn’t feel this way as I feel about Harris. I’m like, do I want to run for office? If she can do it, I can. She looks just like me, right? She represents, she works at McDonald’s. She paid for every. It’s relatable. And that’s what everybody needs.

We’re going to break that glass ceiling. I’m getting teary, teary in my eyes. And it just means so much to be inclusive.

[WHIMSICAL MUSIC]

What does it mean to you that Kamala Harris is a woman? What does it mean to you that she’s a Black woman?

To have a Black woman become the president of the United States, and for her to turn the world upside down in 30 days, to know that I’m in the midst of this miraculous history is phenomenal.

One delegate who really stood out to us was Beverly Hatcher, a 76-year-old Black woman from Texas.

I was raised by a wonderful Baptist mama. I just lost her. But I am who I am because of my mother. We were always pushed to do whatever we wanted to do. I’ll never forget. I wanted to be a majorette. I taught myself, because we had no money for, what is it called, lessons

And a majorette is like the baton twirler, right?

Yes. And when I did finally try out in my 11th grade, I won right off. And my classmates, who were predominantly white, as years have gone by, have told me at class reunions and stuff, Beverly, the sleepy town of Wellington woke up.

Oh, my god, we got a Black girl getting ready to be the head majorette. But it happened because I had the drive and the will. My mother and my family stood behind me, and didn’t miss a parade, or a football game, or a basketball game.

And you see that in Harris?

Beverly, what would your mom say if she saw this?

My sisters have been telling me every day how proud my mom is. And I’m just happy. I’m happy to make her happy. Yeah.

We women, who have had mothers like Kamala, like Michelle, I remember Hillary’s mother, we women value their strength and their wisdom. And we’re just glad that they gave us a legacy to pass it on.

Thank you very much.

We’ll be right back.

Reid, hello.

OK. Kamala Harris just wrapped up her acceptance speech. Before we talk about what she said and the case she presented, tell us how her campaign was thinking about the stakes of this moment.

Sabrina, this evening was one of two opportunities, along with the debate next month, for her to speak to tens of millions of people at once. And so for that, the stakes were really high.

Her goal was to present herself as a serious person and a serious candidate, who was not the candidate who flamed out in 2019 or the unsteady vice president from the beginning of her term. She had to show that she had the gravitas to be the commander in chief, the political aptitude to reach out to the middle, and also to progressives in her party all at the same time.

A very tall order. Tell us how she went about doing that.

Good evening, everyone. Good evening.

Well, she started talking around 9:30 Chicago time to a packed United Center with 14,000 or 15,000 people, many, many wearing all white, the color of the suffragettes, a color that makes a statement just by wearing it. And when Harris took the stage —

— they erupted in a cheer that forced her for a couple of minutes to wait before she could start talking.

Thank you. OK, let’s get to business. Let’s get to business. All right.

And what did she finally say once she started talking?

She told the story of her life.

The path that led me here in recent weeks was, no doubt, unexpected. But I’m no stranger to unlikely journeys.

My mother, our mother, Shyamala Harris, had one of her own. And I miss her every day, and especially right now.

She talked about the influence of her mother, who raised her and her sister.

And she also taught us, “And never do anything half-assed.” And that is a direct quote. [LAUGHS]

She spoke about her family’s humble beginnings in Oakland.

Before she could finally afford to buy a home, she rented a small apartment in the East Bay.

Then she started talking about her career as a prosecutor.

In the courtroom, I stood proudly before a judge and I said five words.

She brought back one of the lines that she used in her 2020 campaign about how when she stood up in a courtroom, she began with the same words.

Kamala Harris for the people.

And she said she would bring that same philosophy to the White House, that she was not working for specific individuals, but for the people at large.

And so on behalf of the people —

Eventually she did a bigger wind up to formally accepting the nomination.

— on behalf of every American, regardless of party, race, gender, or the language your grandmother speaks —

And listed the people on whose behalf she did so.

— on behalf of everyone whose story could only be written in the greatest nation on Earth —

It was really a kind of a feat of speech writing to build up to this big emotional moment.

— I accept your nomination to be president of the United States of America.

And what did you make of that, how she was doing that?

It was building up this speech to be a serious political document and present her as a serious figure in this moment. And so she still has to prove to people that she is capable of being the commander in chief and running the country.

And how does she try to prove that she’s capable of being a commander in chief?

What she did was try to draw the distinction between herself and Donald Trump.

In many ways, Donald Trump is an unserious man. But the consequences, but the consequences of putting Donald Trump back in the White House are extremely serious.

And she warns that Trump would not have guardrails on him if he were elected to a second term.

Just imagine Donald Trump with no guardrails.

And how he would use the immense powers of the presidency of the United States not to improve your life, not to strengthen our national security, but to serve the only client he has ever had, himself.

The speech was very clear-eyed about the stakes of the election.

They know Trump won’t hold autocrats accountable because he wants to be an autocrat himself.

There was a whole section in the middle of the speech where she ticked through, one by one, a whole series of warnings about things that Trump would do to the country if he were back in the White House.

Get this, he plans to create a national anti-abortion coordinator and force states to report on women’s miscarriages and abortions.

Simply put, they are out of their minds.

What else stuck out to you?

It was remarkable, the section of the speech where she talked about Gaza.

President Biden and I are working around the clock, because now is the time to get a hostage deal and a ceasefire deal done.

She did not veer too far to the left.

I will always stand up for Israel’s right to defend itself.

She managed to say things that would be appealing to both sides.

President Biden and I are working to end this war, such that Israel is secure, the hostages are released, the suffering in Gaza ends, and the Palestinian people can realize their right to dignity, security, freedom, and self-determination.

It was a remarkable moment to hear the arena erupt at the end of that section, to hear her support for both the Israelis and the Palestinians reveal that kind of enthusiasm, after the party has been really ripped apart for months about how to handle the situation.

Fellow Americans, I love our country with all my heart.

She ended this speech with a paean to patriotism.

We are the heirs to the greatest democracy in the history of the world.

She dove headlong into the American exceptionalism argument that is native to Republicans and to older generations of politicians, like Joe Biden.

It is now our turn to do what generations before us have done. Guided by optimism and faith to fight for this country we love. To fight —

But is not something you always hear from younger Democrats, who are a little less comfortable with some of the flag waving.

Let’s vote for it. And together, let us write the next great chapter in the most extraordinary story ever told. Thank you. God bless you and may God bless the United States of America. Thank you all.

She seemed to really be taking aim at this criticism of her, which is that she’s this radical California liberal and she can’t be trusted with the keys to the country.

I mean, that was one of the tasks that she had tonight, was to make the argument, particularly to voters in the middle, the suburban voters that used to vote for Republicans, but have been repelled by Trump and driven to Democrats in the last several years, that they can vote for her without worrying that she’s some kind of Bernie Sanders acolyte.

And some of that is based on the way she ran her last presidential campaign. Some of it, frankly, is because she’s a Black woman from California. And that the voters who will determine this election are voters in less diverse states, for the most part.

So Reid stepping back here, it feels worth remembering just where we were at the end of the Republican National Convention that was just over a month ago. Things couldn’t have felt more different. The GOP was on top of the world, while the Democrats were in disarray over Biden’s refusal to leave the race.

And now here we are. And it feels like things couldn’t be better for the Democrats. At least that’s the feeling I’m having coming out of this convention.

I mean, the whole race has turned upside down from where it was when we left Milwaukee. And Democrats are upbeat. They are confident. It is a party that is remarkably united behind their candidate.

But you have to remember, this election will be very close. It is, indeed, a game of inches in the key battleground states. And what she was trying to do was to present herself as someone who can be trusted as commander in chief to win over the tiny slices of the electorate that will determine the winner in places like Wisconsin, and Michigan, and Pennsylvania, Georgia, and Arizona.

And those are the states that will determine the election. And they have made a calculated decision that those voters needed to see her as a commander in chief, something they had not seen from her before. And we will see in the coming days and weeks whether she’s accomplished that in a way that brings enough of those people on board for her to win a term as president.

Reid, thank you.

Thank you, Sabrina. [WHIMSICAL MUSIC]

Here’s what else you should know today. On Thursday, the Supreme Court allowed Arizona Republicans, for now, to impose tougher voting requirements, including a new rule that people registering to vote there before the coming election must show proof of citizenship.

As a result, Arizonans newly registering to vote for this year’s presidential election must provide copies of one of several documents, such as a birth certificate or a passport, in order to prove that they are US citizens. Democrats have denounced the new rule as an attempt to prevent legal immigrants from voting.

And US Health officials have approved the latest slate of annual COVID vaccines, clearing the way for Americans six months and older to receive updated shots in the coming days. The approvals come amid a prolonged surge of COVID infections, which have risen all summer.

Remember to catch a new episode of “The Interview” right here tomorrow. This week, Lulu Garcia-Navarro talks with Jenna Ortega, the star of the Netflix series “Wednesday,” and the new “Bettlejuice” sequel, about her head-spinning success over the past few years.

One day I just I woke up in somebody else’s shoes. I felt like I had entered somebody else’s life. And I didn’t know how to get back to mine.

Today’s episode was produced by Lynsea Garrison, Rob Szypko, Jessica Cheung, Asthaa Chaturvedi, and Shannon Lin. It was edited by Rachel Quester, contains original music by Rowan Niemisto, Dan Powell, Diane Wong, and Marion Lozano, and was engineered by Chris Wood. Our theme music is by Jim Brunberg and Ben Landsverk of Wonderly.

[THEME MUSIC]

That’s it for “The Daily.” I’m Sabrina Tavernise. See you on Monday.

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what is the problem solving theory of dreams

Hosted by Sabrina Tavernise

Featuring Astead W. Herndon and Reid J. Epstein

Produced by Lynsea Garrison Rob Szypko Jessica Cheung Asthaa Chaturvedi and Shannon Lin

Edited by Rachel Quester

Original music by Rowan Niemisto Marion Lozano Dan Powell and Diane Wong

Engineered by Chris Wood

Listen and follow ‘The Daily’ Apple Podcasts | Spotify | Amazon Music | YouTube | iHeartRadio

Last night, at the Democratic National Convention, Vice President Kamala Harris accepted her party’s nomination, becoming the first woman of color in U.S. history to do so.

Astead W. Herndon and Reid J. Epstein, who cover politics for The Times, discuss the story this convention told about Ms. Harris — and whether that story could be enough to win the presidential election.

On today’s episode

Astead W. Herndon , a national politics reporter and the host of the politics podcast “ The Run-Up ” for The New York Times.

Reid J. Epstein , who covers politics for The New York Times.

Kamala Harris and her husband, Doug, stand in front of a photo of the American flag, smiling and embracing.

Background reading

Kamala Harris promised to chart a “new way forward” as she accepted the nomination.

“The Run-Up”: It’s her party now. What’s different?

There are a lot of ways to listen to The Daily. Here’s how.

We aim to make transcripts available the next workday after an episode’s publication. You can find them at the top of the page.

The Daily is made by Rachel Quester, Lynsea Garrison, Clare Toeniskoetter, Paige Cowett, Michael Simon Johnson, Brad Fisher, Chris Wood, Jessica Cheung, Stella Tan, Alexandra Leigh Young, Lisa Chow, Eric Krupke, Marc Georges, Luke Vander Ploeg, M.J. Davis Lin, Dan Powell, Sydney Harper, Michael Benoist, Liz O. Baylen, Asthaa Chaturvedi, Rachelle Bonja, Diana Nguyen, Marion Lozano, Corey Schreppel, Rob Szypko, Elisheba Ittoop, Mooj Zadie, Patricia Willens, Rowan Niemisto, Jody Becker, Rikki Novetsky, Nina Feldman, Will Reid, Carlos Prieto, Ben Calhoun, Susan Lee, Lexie Diao, Mary Wilson, Alex Stern, Sophia Lanman, Shannon Lin, Diane Wong, Devon Taylor, Alyssa Moxley, Olivia Natt, Daniel Ramirez and Brendan Klinkenberg.

Our theme music is by Jim Brunberg and Ben Landsverk of Wonderly. Special thanks to Sam Dolnick, Paula Szuchman, Lisa Tobin, Larissa Anderson, Julia Simon, Sofia Milan, Mahima Chablani, Elizabeth Davis-Moorer, Jeffrey Miranda, Maddy Masiello, Isabella Anderson, Nina Lassam and Nick Pitman.

Astead W. Herndon is a national politics reporter and the host of the politics podcast “The Run-Up.” More about Astead W. Herndon

Reid J. Epstein covers campaigns and elections from Washington. Before joining The Times in 2019, he worked at The Wall Street Journal, Politico, Newsday and The Milwaukee Journal Sentinel. More about Reid J. Epstein

Problem-solving in dreams (famous examples)

In dreams, while our conscious mind is inactive, our subconscious mind is actively working on problems that we may have failed to solve consciously in our waking life. That’s why it’s highly likely that a solution to a problem that you’ve been working on for quite a while can pop up in your dream.

This is similar to when, for example, you are thinking hard about a problem and then you let go of it because you can’t come up with a solution. And then after a while, when you’re involved in some other unrelated activity, the solution to your problem suddenly pops up from nowhere. You say you had an insight .

This happens because as soon as you let go of the problem consciously, your subconscious mind is still working on solving it behind the scenes.

Once it solves the problem, it gets ready to launch the solution into your consciousness as soon as it comes across a trigger that’s in some way similar to the solution- an image, a situation, a word, etc.

Examples of some famous solutions found in dreams

Dreams not only help you understand your own psychological makeup but also solve your complex daily life problems for you. If you aren’t maintaining a dream journal yet, the following anecdotes will surely motivate you to record your dreams…

Structure of benzene

August Kekule had been trying to figure out how atoms in the benzene molecule arranged themselves but couldn’t come up with a plausible explanation. One night he dreamed of dancing atoms that gradually arranged themselves in the form of a snake.

The snake then turned around and swallowed its own tail, forming a ring-like shape. This figure then kept dancing in front of him.

Upon waking up Kekule realized that the dream was telling him that benzene molecules were made of rings of carbon atoms.

The problem of the shape of the benzene molecule was solved and a new field called aromatic chemistry came into existence that significantly advanced the understanding of chemical bonding.

Transmission of nerve impulses

Otto Loewi believed that nerve impulses were transmitted chemically but he had no way to demonstrate it. For years he searched for ways to prove his theory experimentally.

One night he dreamed of an experimental design that he could possibly use to prove his theory. He carried out the experiments, published his work and finally confirmed his theory. He later won a Nobel prize in medicine and is widely regarded as the ‘father of neuroscience’.

Mendeleev’s periodic table

Mendeleev wrote names of the different elements along with their properties on cards that he laid out in front of him on his table. He arranged and re-arranged the cards on the table trying to figure out a pattern.

Exhausted, he fell asleep and in his dream he saw the elements getting arranged in a logical pattern according to their atomic weights. Thus the periodic table was born.

The golf swing

Jack Nicklaus was a golf player who hadn’t been doing well lately. One night he dreamed that he was playing very well and noticed that his grip on the golf club was different than what he actually used in the real world. He tried the grip that he’d seen in the dream and it worked. His golfing skills greatly improved.

The sewing machine

This is the anecdote that I found most fascinating. Elias Howe, the inventor of the modern sewing machine, faced a great dilemma while making the machine. He didn’t know where to provide an eye to his sewing machine needle. He couldn’t provide it at the tail, as is usually done in hand-held needles.

One night, after he had spent days figuring out a solution, he saw a dream in which he had been assigned the task of making a sewing machine by a king. The king gave him 24 hours to make it or else he would be executed. He struggled with the same problem of the needle eye in the dream. Then the time of execution arrived.

While he was being carried by the guards for execution, he noticed their spears were pierced at the tips. He had found the answer! He should provide the eye to his sewing machine needle at its pointed tip! He begged for more time and whilst begging he woke up. He rushed to the machine that he had been working on and solved his problem.

Dreams and creativity

Dreams can not only provide us with solutions to problems but also give us creative insights.

Stephen King’s plot for his famous novel Misery was inspired by a dream, so was Stephanie Meyer’s Twilight . Mary Shelly, the creator of the Frankenstein monster, had actually seen the character in a dream.

The Terminator, created by James Cameron, was also inspired by a dream. Paul McCartney of The Beatles one day ‘woke up with a tune in his head’ and the song ‘Yesterday’ now has the Guinness world record for the greatest number of covers.

Hi, I’m Hanan Parvez (MA Psychology). I’ve published over 500 articles and authored one book. My work has been featured in Forbes , Business Insider , Reader’s Digest , and Entrepreneur .

Why We Dream: Real Reasons Revealed

BOSTON – The slumbering mind might not seem like an apt tool for any critical thinking, but humans can actually solve problems while asleep, researchers say. Not only that, but one purpose for dreaming itself may be to help us find solutions to puzzles that plague us during waking hours.

Dreams are highly visual and often illogical in nature, which makes them ripe for the type of "out-of-the-box" thinking that some problem-solving requires, said Deirdre Barrett, a psychologist at Harvard University.

Barrett's theory on dreaming , which she discussed at the Association for Psychological Science meeting here last month, boils down to this: Dreaming is really just thinking, but in a slightly different state from when our eyes are open. [Why we dream is just one mystery of the mind.]

"Whatever the state we're put in, we're still working on the same problems," Barrett said. Although dreams might have initially evolved for a different purpose, they likely have been refined over time so they can serve double-duty: help the brain reboot itself and problem-solve.

Dreams and evolution

A theory to explain dreams, or any human behavior for that matter, needs to take into account evolution, Barrett said. But many early theories of dreaming either didn't address evolution at all, or downright contradicted it, she said.

For instance, Sigmund Freud proposed dreams exist to fulfill our wishes. But such gratification in an imaginary world would do little to help us adapt our instincts to the physical world, which is one key point of evolution, Barrett said.

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Others have proposed dreams are more of a side effect of the sleep cycle. Dreams usually occur during Rapid Eye Movement, or REM, sleep. This stage is thought to serve several functions: to rest a part of the brain (since some areas are active while others aren't) and to replenish brain chemicals, such as neurotransmitters.

This has led some to say that dreams happen simply because REM sleep happens, Barrett said. The psychologist Steven Pinker once likened dreams to computer screen savers, saying that it perhaps "doesn't really matter what the content is as long as certain parts of the brain are active."

However, Barrett disagrees. "My opinion is that, evolution just isn't wasteful, that when things evolve for one purpose, that generally they don't continue throughout time to have only that purpose, but anything else that may be useful about them gets refined," she said in a telephone interview with LiveScience prior to the convention.

She also noted that REM sleep has been around for quite some time, since mammals evolved some 220 million years ago. "The longer something has existed during evolutionary history, the likelier it is to have other functions overlaid on it," she said at the convention.

Problem-solving

Barrett has studied problem-solving in dreams for more than 10 years, and documented many examples of the phenomenon.

In one experiment, Barrett had college students pick a homework problem to try to solve in a dream. The problems weren't rocket science; they were fairly easy questions that the student simply hadn't gotten around to solving yet. Students focused on the problem each night before they went to bed. At the end of a week, about half the students had dreamed about the problem and about a quarter had a dream that contained the answer, Barrett said.

So at least in the cases where problems are relatively easy, some people can solve them in their sleep.

Barrett has also extensively reviewed scientific and historical literature, looking for examples of problems solved in dreams.

She found examples of almost every type of problem being solved in a dream, from the mathematical to the artistic. But many were related to problems that required individuals to visualize something in his or her mind, such as an inventor picturing a new device.

The other major category of problems solved in dreams included "ones where the conventional wisdom is just wrong about how to approach the problem," Barrett said.

Dreams might have evolved to be particularly good at allowing us to work out puzzles that fall into those two categories, she said.

"I think that dreams and REM sleep have probably further evolved to be useful for really as many of the things that our thinking is useful for," Barrett said. "It's just extra thinking time, so potentially any problem can get solved during it, but it's thinking time in the state that's very visual and looser in associations, so we've evolved to use it especially to work on those kinds of problems."

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Rachael is a Live Science contributor, and was a former channel editor and senior writer for Live Science between 2010 and 2022. She has a master's degree in journalism from New York University's Science, Health and Environmental Reporting Program. She also holds a B.S. in molecular biology and an M.S. in biology from the University of California, San Diego. Her work has appeared in Scienceline, The Washington Post and Scientific American.

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Dreams and creative problem-solving

Affiliation.

1 Department of Psychiatry, Harvard Medical School, Cambridge, Massachusetts.
PMID: 28640937
DOI: 10.1111/nyas.13412

Dreams have produced art, music, novels, films, mathematical proofs, designs for architecture, telescopes, and computers. Dreaming is essentially our brain thinking in another neurophysiologic state-and therefore it is likely to solve some problems on which our waking minds have become stuck. This neurophysiologic state is characterized by high activity in brain areas associated with imagery, so problems requiring vivid visualization are also more likely to get help from dreaming. This article reviews great historical dreams and modern laboratory research to suggest how dreams can aid creativity and problem-solving.

Keywords: REM sleep; creativity; dream incubation; dreams; problem-solving.

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What Is the Activation-Synthesis Model of Dreaming?

Origins of the theory, the sleeping brain, key things to remember, reaction to the theory, are dreams meaningless, the aim model of dreaming.

The activation-synthesis theory is a neurobiological explanation of why we dream. The question of why people dream has perplexed philosophers and scientists for thousands of years, but it is only fairly recently in history that researchers have been able to take a closer look at exactly what happens in the body and brain during dreaming.

Harvard psychiatrists J. Allan Hobson and Robert McCarley first proposed their theory in 1977, suggesting that dreaming results from the brain's attempt to make sense of neural activity that takes place during sleep.

Even when you are sleeping, your brain is active. Hobson and McCarley suggested that during sleep, activity in some of the lower levels of the brain that are primarily responsible for basic biological processes are then interpreted by the parts of the brain responsible for higher-order functions such as thinking and processing information.

The activation-synthesis model suggests that dreams are caused by the physiological processes of the brain. While people used to believe that sleeping and dreaming was a passive process, researchers now know that the brain is anything but quiet during sleep.

So what sort of things are happening in the sleeping brain? A wide variety of neural activity takes place as we slumber.

Sleep helps the brain perform a number of activities including cleaning up the brain and consolidating memories from the previous day. Activation-synthesis theory suggests that the physiological processes that take place as we sleep are the cause of dreams.

Brain Activity Plays a Role in Dreaming

How does brain activity during sleep lead to dreaming?

According to Hobson and other researchers, circuits in the brain stem are activated during REM sleep.
Once these circuits are activated, areas of the limbic system involved in emotions , sensations, and memories, including the amygdala and hippocampus , become active.
The brain synthesizes and interprets this internal activity and attempts to create meaning from these signals, which results in dreaming.

Common Characteristics of Dreams

Hobson also suggested that there are five key characteristics of dreams. Dreams tend to contain illogical content, intense emotions, acceptance of strange content, strange sensory experiences, and difficulty remembering dream content.

To summarize, the activation-synthesis theory essentially made three key assumptions:

High levels of activity in the brainstem are necessary for dreaming to take place.
Activation in these areas of the brain results in REM sleep and dreaming, and by corollary, all dreaming takes place during REM sleep.
The forebrain attempts to place meaning on the random signals created from the activation of the brainstem, resulting in coherent dreams.

So why does the brain try to make meaning from these random signals that take place during sleep?

"The brain is so inexorably bent upon the quest for meaning that it attributes and even creates meaning when there is little or none in the data it is asked to process," Hobson suggested.

The initial publication of their research stirred up considerable controversy, particularly among Freudian analysts. Because many dream researchers and therapists invest considerable time and effort trying to understand the underlying meaning of dreams , the suggestion that dreams were simply the brain's way of making sense of activity during sleep did not sit well with many.

While the activation-synthesis model of dreaming relies on physiological processes to explain dreaming, it does not imply that dreams are meaningless.

According to Hobson, "Dreaming may be our most creative conscious state, one in which the chaotic, spontaneous recombination of cognitive elements produces novel configurations of information: new ideas. While many or even most of these ideas may be nonsensical, if even a few of its fanciful products are truly useful, our dream time will not have been wasted."

Thanks to modern advances in brain imaging and the ability to monitor brain activity, researchers now understand more about the sleep-wake cycle, the different stages of sleep, and the different states of consciousness .

The more recent version of the activation-synthesis theory is known as the AIM model, standing for activation, input-output gating, and modulation.

This newer model tries to capture what happens in the brain-mind space as consciousness changes through waking, non-REM, and REM sleep states.

A Word From Verywell

The reasons and meanings behind dreaming have fascinated philosophers and researchers for centuries. Activation-synthesis theory added an important dimension to our understanding of why we dream and stressed the importance of neural activity during sleep.

As new technology emerges for studying the brain and sleep processes, researchers will continue to make new advances in our understanding of why we dream, in knowledge regarding states of consciousness, and in comprehending the possible meaning behind our dreams.

Hobson JA, McCarley RW. The brain as a dream-state generator: An activation-synthesis hypothesis of the dream process. Am J Psychiatry. 1977;134(12):1335-1348. doi:10.1176/ajp.134.12.1335

Oniz A, Inanc G, Taslica S, Guducu C, Ozgoren M. Sleep Is a Refreshing Process: An fNIRS Study. Front Hum Neurosci . 2019;13:160. doi:10.3389/fnhum.2019.00160

American Psychological Association. APA Dictionary of Psychology. AIM Model. Washington, DC: American Psychological Association 2020 https://dictionary.apa.org/aim-model

Hobson, JA. REM sleep and dreaming: Towards a theory of protoconsciousness. Nature Reviews Neuroscience . 2010;10(11): 803–813. doi:10.1038/nrn2716

By Kendra Cherry, MSEd Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."

November 1, 2011

14 min read

Answers in Your Dreams

When you fall asleep, you enter an alternative state of consciousness--a time when true inspiration can strike

By Deirdre Barrett

As a young mathematician in the 1950s, Don Newman taught at the Massachusetts Institute of Technology alongside rising star and Nobel-laureate-to-be John Nash. Newman had been struggling to solve a particular math problem: “I was ... trying to get somewhere with it, and I couldn’t and I couldn’t and I couldn’t,” he recalled.

One night Newman dreamed that he was reflecting on the problem when Nash appeared. The sleeping Newman related the details of the conundrum to Nash and asked if he knew the solution. Nash explained how to solve it. Newman awoke realizing he had the answer! He spent the next several weeks turning the insight into a formal paper, which was then published in a mathematics journal.

Newman is hardly alone in making a practical breakthrough during a night of sleep. While dreaming, Friedrich August Kekulé came up with the structure of benzene, Dmitry Mendeleyev conjured up his final form of the periodic table of the elements and Otto Loewi thought of the neuroscience experiment that won him a Nobel Prize in medicine. Modern engineers Paul Horowitz and Alan Huang dreamed designs for laser-telescope controls and laser computing, respectively. Innumerable artists and filmmakers have depicted images that came to them in their sleep. Mary Shelley dreamed the two main scenes that became Frankenstein , and Robert Louis Stevenson did the same with Dr. Jekyll and Mr. Hyde . Ludwig van Beethoven, Paul McCartney and Billy Joel all awoke to discover new tunes ringing in their minds. Mahatma Gandhi’s call for a nonviolent protest of British rule of India was inspired by a dream.

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Yet dreams so often seem incoherent, bizarre or even trivial. We search intensely for our brother in an endless maze of corridors because we must give him a yellow package. But when we find him, we have forgotten the package—which we are certainly not holding any longer—and anyway he is now a neighbor, not a brother. Other dreams are ephemeral—we wake up thinking about a yellow box, but that is all we recall.

For decades scientists have puzzled over how dreams could display such diverse characteristics. Research is beginning to suggest that dreams are simply thought in a different biochemical state. The physiological demands of sleep alter the way the brain functions. Dreams may seem bizarre or nonsensical because the chemistry of the sleeping brain affects how we perceive our own thoughts, but we nonetheless continue focusing on all the same issues that concern us while we are awake. This unusual state of consciousness is often a blessing for problem solving—it helps us find solutions outside our normal patterns of thought. By following a few simple steps, we can even harness this power, encouraging our sleeping brain to ruminate on particular concerns.

Anatomy of a Dream

One often hears the question, “What is dreaming for?” You would never pose such a simplistic query about waking thought. It is for everything.

Nevertheless, theorists have long offered one-function explanations for dreaming. Sigmund Freud believed that dreams primarily express repressed wishes, namely, infantile sexual and aggressive impulses. Other psychoanalysts thought they had more to do with narcissistic strivings or compensation for feelings of inferiority. More recently, psychologists have posited that dreams simulate threats or help to consolidate memories. All these theories characterize some dreams, but none of them can account for every type. Just as waking thought can drift between reminiscing, planning, rumination, and so on, dream cognition seems to encompass many modes of thought.

Most early theorists assumed that the dreams we remembered constituted all dreams. Several hypotheses supposed that people experienced dreams when some specific situation triggered a set of distinctive feelings—the desire for sex, say, or a bruised ego. In the 1950s, however, a series of groundbreaking studies by Eugene Aserinsky and Nathaniel Klietman, both then at the University of Chicago, revealed that people have many more dreams than they are likely to remember. The two sleep researchers discovered that human slumber consists of approximately 90-minute cycles, each one containing a period of rapid eye movement (REM) and heightened brain activity—about as much activity as when we are awake. When the scientists awakened people near the end of each REM period, the sleepers recounted an average of almost five dreams per night. The discrepancy between the subjects’ reports when awakened right after the REM period, as opposed to later, led the scientists to conclude that dreams almost always accompany this stage of sleep even if none are recalled by morning.

Within the past two decades positron-emission tomography (PET) scans have allowed us to see which brain areas are involved in dreaming. Parts of the cortex associated with visual imagery and the perception of movement become activated even more dramatically than when we are awake, as do some deep brain areas associated with emotion. In contrast, the dorsolateral prefrontal cortex is less engaged during dreaming; this area is associated with volitional action and the evaluation of what is logical and socially appropriate. These PET results fit the characteristics of dreams well; dream reports almost always contain visual imagery and often involve movement. The prefrontal findings fit neatly with the fact that dreams have long been associated with less “censorship”—not only in the Freudian sense of uninhibited sex and aggression but also in terms of filtering out scenarios that are illogical or abnormal. We will return to this point when discussing problem solving. Sometimes tackling a puzzle the “wrong” way can lead to surprising insights.

Evolutionary psychologists were quick to point out that this PET portrait of the dreaming brain makes sense because such activity would have supported human survival—certain areas of the brain are safer to turn on and off during sleep than others. Donald Symons, an anthropologist at the University of California, Santa Barbara, argued in his 1993 paper “The Stuff That Dreams Aren’t Made Of” that sleepers must monitor the environment with specific senses—to smell smoke, hear intruders, sense temperature changes and feel pain. Hallucinating vividly in those sensory modes might lead us to wake up frequently in an unnecessary panic, or, even worse, over a long period we might evolve a threshold of tolerance that would cause us to block our real warnings. Our eyes can be closed, however, as we do not need to monitor our visual environment during sleep. And our bodies can be paralyzed, as is normal during REM sleep, because we do not need to move—in fact, we should not move until we awaken.

Evolution, then, may help elucidate why certain brain areas are more or less active when we sleep. The pattern of activity explains why dreams have the characteristics they do—visually rich and logically loose. At first, these exciting physiological findings gave rise to a proliferation of theories that dreams were just an epiphenomenon, or side effect, of the brain patterns during slumber. Sleep researchers often referred to REM activity as “random,” although no evidence suggested it was any more random than waking brain activity. Many theorists leaped to pronounce dreams “explained.”

I reiterate: we would never dismiss waking thought so quickly. Knowing that our prefrontal cortex is active when we encounter a social prohibition does not explain away the subjective debate we experience when deciding how to respond. Likewise, describing a dream’s content or its associated brain activity does not answer the question of its purpose. Brain researchers finally grasped this fact after a two-decade lull and in the past few years have begun studying dreams seriously again.

Sleep on It

By the 1990s a growing body of research suggested that slumber is important for consolidating new learning: even very early studies had shown that sleeping for a while after learning something new results in much better recall than after spending the same amount of time awake. More recent findings hint at a special role for REM sleep in memory consolidation. Studies of rats learning to navigate mazes have found that during REM sleep, brain activity mimics that of the awake rodent training in the maze, which suggests that circuits may be reinforced during REM sleep. In humans, too, research supports the role of REM sleep in memory. The more REM sleep subjects get after learning, the better they recall emotionally charged material [see “ Quiet! Sleeping Brain at Work ,” by Robert Stickgold and Jeffrey M. Ellenbogen; Scientific American Mind , August/September 2008].

In 2009 psychologists at the University of California, San Diego, examined whether REM facilitated more than just memory when learning. They gave their subjects a test that required creative problem solving and then dropped hints about the answers. The subjects then spent some time either awake, in non-REM sleep only or in REM sleep before taking the test again. The REM sleep group showed the most improvement on their creative solutions to the previously presented problems.

The same year in Robert Stickgold’s lab at Harvard University, a team led by postdoctoral researcher Ina Djonlagic had subjects learn a complicated system of weather prediction. The students were shown a combination of images, each representing a probability of sun or rain. The students did not know the meaning of the images, but they attempted to figure them out through trial and error by predicting an overall chance of sun or rain and getting feedback on their answers. The researchers found that subjects who nodded off before doing the task again were more likely to discover the general rule behind the images’ meaning through an “aha!” type of insight than those who stayed awake. In addition, their heightened performance, as well as their ability to explicitly articulate that they had grasped the general rule, was correlated with the amount of REM sleep they had gotten.

Further research confirms that REM sleep aids in problem solving. In a series of ongoing studies in the same Harvard lab, postdoctoral researcher Erin Wamsley asks subjects to navigate a virtual maze. After some practice, they get either a waking break, REM sleep or a non-REM sleep period. As Wamsley reported at the 2011 SLEEP conference, only REM sleep sharpens participants’ performance. In addition, when she wakes or interrupts them to ask what they are thinking or dreaming, the theme is often the maze—but only when this thinking occurs in REM sleep do subjects fare better the next time they tackle the real maze.

Because REM sleep is the stage during which dreams occur, these sleep studies imply that dreaming might have something to do with creative problem solving. Mounting experimental evidence, as well as countless anecdotes of solutions that popped up during dreams, supports this idea.

The first study on dreams and objective problem solving was conducted more than a century ago. In 1892 Charles M. Child of Wesleyan University asked 186 college students whether they had ever addressed a problem in a dream. One third said they had. The students reported playing a chess game, solving an algebra problem, detecting a bookkeeping error and translating a passage from Virgil while slumbering.

The next major breakthrough came when researchers decided to try seeding people’s dreams with a specific problem. In 1972 sleep researcher William Dement of Stanford University asked 500 of his students to spend 15 minutes a night trying to solve brainteasers, making sure that they fell asleep with an unsolved problem on their mind. Students reported having 87 dreams, seven of which solved a brainteaser.

Such puzzles are a useful tool for testing creative problem solving because people are likely to get stuck before having an “aha!” moment of insight. Yet these brainteasers may be beyond the ability of some subjects, and they are also not of great personal import. In Dement’s study, which lasted three nights, all the correct answers came during the first night. He surmised that students lost motivation quickly on problems of little relevance to their lives. Therefore, in my own research in 1996, I took a different approach. I asked students to select their own objective problem. They recorded their dreams for a week and noted the ones they thought addressed the issue or contained a satisfactory solution. Two research assistants also judged whether the dreams focused on or solved the problems.

Most of my subjects chose problems that appeared simpler than Dement’s brainteasers. Half of them had dreams they felt touched on their concern, and one third dreamed a solution to it. Judges rated only slightly fewer dreams as tackling or solving problems. Although a number of the problems had to do with homework or mundane tasks such as rearranging furniture, some of the most interesting solutions came up in dreams about major life decisions. For instance, this dilemma was rated as solved by both the dreamer and the judges:

Problem : I have applied to two programs in clinical psychology and two in industrial psychology because I can’t decide which field I want to go into.

Dream : There’s a map of the U.S., and I’m in a plane flying over this map. The pilot says we’re having engine trouble and need to land. We look for a safe place on the map, indicated by a light. I ask about Massachusetts, which we’re right over, but he says that all of Massachusetts is very dangerous. The lights seemed to be farther west.

Solution : I woke up and realized that my two clinical schools are both in Massachusetts, where I have spent my entire life and where my parents live. Both industrial programs are far away, in Texas and California. This is because originally I was looking to stay close to home, and there were no good industrial programs nearby. I realized that there is a lot wrong with staying at home, and funny as it sounds, getting away is probably more important than which kind of program I go into.

A Portal to Creativity

The all-time most famous dream example—Kekulé realizing that the structure of benzene was a closed ring after dreaming of a snake made of atoms taking its tail in its mouth—illustrates the two distinctive features of problem solving in dreams. Recall that the brain areas that usually restrict our thinking to the logical and familiar are much less active during REM sleep. Many studies of creativity suggest that such disinhibition is a crucial component of creative thought [see “ The Unleashed Mind ,” by Shelley Carson; Scientific American Mind , May/June 2011]. Similarly, the high activity in the visual areas of the sleeping brain allows it to visualize solutions more readily than in waking thought. Kekulé had been stumped because all known molecules were straight lines with side chains, and he had assumed, wrongly, that benzene would follow suit.

My research confirms that dreamed solutions tend to have unusual visual characteristics. Through the late 1990s I scoured the existing literature on dreams, professional biographies and history books for examples of problem-solving dreams, and I queried working professionals as to whether they had ever had dreams that were useful in their jobs. Certain patterns emerged. Well over half of the visual artists said they had used dreams in their work. About half of fiction writers had. The numbers dropped off rapidly as the professions became more abstract. Within the sciences, inventors, engineers and others who benefit from visualizing problems in three dimensions were likelier to report helpful dreams. Some dreamers even had multiple examples of having awakened with a solution and had developed an explicit bedtime incubation routine.

In my present study, for which I reported preliminary results in June at the International Association for the Study of Dreams Conference, I investigated how dream-based problem solving might benefit working men and women more broadly. Professionals aged 21 to 69 attempted to solve real work-related problems in their sleep. These subjects seemed to dream about their problems with the same frequency as the college students I had observed in 1996; however, they reported less than half the number of solutions as compared with the students. The work-related problems may simply be more difficult than the college students’ dilemmas, and because this group is older, the subjects may not recall as many dreams. A significant number of them, however, report having a useful dream after only one week of incubation practice.

Your Dreams

Shortly after my book The Committee of Sleep was published in 2001, I heard Newman recount his story on a PBS show about John Nash and the film A Beautiful Mind . A year later I was unexpectedly seated next to Nash at a dinner party. I asked him about the incident, which he remembered well. “Don actually included a footnote thanking me in the paper,” Nash chuckled, “and he kept acting grateful, like I’d actually helped him when it was his dream.” I came across that remark often in my survey. Solutions frequently came from a dream character—one computer programmer got repeated nocturnal lessons from Albert Einstein—and people had trouble taking full credit for what their dreaming mind had done. This tendency fits brain findings for REM sleep in which the dorsolateral prefrontal cortex, associated with perceptions of volition, is less active.

But we need not wait passively for inspiration to strike. We spend almost a third of our lives asleep—and almost a third of that time dreaming. My research suggests that in a short amount of time, people can learn to focus their dreams on minor problems and often solve them. As for the bigger concerns, surveys find that all kinds of mysteries can be revealed in dreams—two Nobel Prizes resulted from dreams, after all. But even if you choose to leave your sleeping brain alone, pay attention: after nodding off, your brain in its altered state of consciousness is very likely already hard at work.

Deirdre Barrett is a psychologist on the faculty of Harvard Medical School and author of the book The Committee of Sleep (paperbound, Oneiroi Press, 2010).

Solving Problems in Your Dreams

How to combine your next all-nighter with meaningful rest..

Posted August 29, 2015 | Reviewed by Ekua Hagan

You’ve likely heard a few stories of people happening upon fame-making discoveries in their dreams. Nobel Prize laureate Otto Loewi dreamed about the experiment which would prove his idea that nerve impulses are chemically transmitted. Pro-golfer Jack Nicklaus ended his run of poor scores after realizing he had been holding the club incorrectly. Frankenstein author Mary Wollstonecraft Godwin hit on the idea for the book after experiencing a vision of the hideous phantasm laying stretched out on a table.

But the ability to utilize sleep as a problem-solving technique isn’t limited to a select few. We all are capable of making similarly important discoveries in our own dreams. The key is to gain lucidity.

Lucid dreaming is a hybrid state that is characterized by both waking and dream consciousness. Although it’s biomechanically similar to ordinary sleep, the consciousness accompanying lucid dreams lies in the higher activity level of the frontal areas of the brain. This is also a feature of very vivid and active states of waking consciousness, such as deep concentration and active listening. But the fact that you’re not living reality means that lucid dreaming differs from conscious experience in one dramatic way: You can learn to control the narrative of your own dreams.

We’ve come across many individuals who regularly use lucid dreaming to tackle problems they find difficult to solve in waking life. For example, one author cures acute writer’s block by summoning the characters of the novel in his dreams. One of the characters might say, “Oh, you shouldn’t kill Epstein in chapter 4, because we need him in chapter 12 to resolve everything.” One professional musician hears rock lyrics when he becomes lucid, which he writes down the next day. And one painter dreams he is standing at a door that separates him from his next masterpiece. After walking through the door, he studies the painting that appears and repaints it later from memory .

Lucid dreaming isn’t just for solving puzzles—it can even be used as therapy . For example, kids with frequent nightmares can be taught to get out of their nightmares. When taught to become lucid, they can “step back” and think to themselves “Right. It’s just a dream.”

In fact, lucid dreaming can be very effective in getting rid of general fears and phobias. It can function as a type of cognitive behavior therapy (CBT), a type of treatment employed by many psychologists for severe obsessive-compulsive disorder, among other conditions. The idea behind CBT is the best way to get over fear of a particular situation is to place yourself in that situation over and over again until your brain becomes desensitized to the trigger.

All that I’ve mentioned is just the tip of the iceberg: Learn more about the science of lucid dreaming and other techniques for cognitive enhancement in our newly released book, The Superhuman Mind: Free the Genius in Your Brain , available on Amazon , BAM , Barnes & Noble , and IndieBound .

Kristian Marlow is a graduate student at the University of Missouri-St. Louis and a member of the St. Louis Synesthesia Lab.

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Front Psychol

The Functional Role of Dreaming in Emotional Processes

Dream experience (DE) represents a fascinating condition linked to emotional processes and the human inner world. Although the overlap between REM sleep and dreaming has been overcome, several studies point out that emotional and perceptually vivid contents are more frequent when reported upon awakenings from this sleep stage. Actually, it is well-known that REM sleep plays a pivotal role in the processing of salient and emotional waking-life experiences, strongly contributing to the emotional memory consolidation. In this vein, we highlighted that, to some extent, neuroimaging studies showed that the processes that regulate dreaming and emotional salience in sleep mentation share similar neural substrates of those controlling emotions during wakefulness. Furthermore, the research on EEG correlates of the presence/absence of DE and the results on EEG pattern related to the incorporated memories converged to assign a crucial role of REM theta oscillations in emotional re-processing. In particular, the theta activity is involved in memory processes during REM sleep as well as during the waking state, in line with the continuity hypothesis. Also, the gamma activity seems to be related to emotional processes and dream recall as well as to lucid dreams. Interestingly, similar EEG correlates of DE have been found in clinical samples when nightmares or dreams occur. Research on clinical samples revealed that promoting the rehearsal of frightening contents aimed to change them is a promising method to treat nightmares, and that lucid dreams are associated with an attenuation of nightmares. In this view, DE can defuse emotional traumatic memories when the emotional regulation and the fear extinction mechanisms are compromised by traumatic and frightening events. Finally, dreams could represent a sort of simulation of reality, providing the possibility to create a new scenario with emotional mastery elements to cope with dysphoric items included in nightmares. In addition, it could be hypothesized that the insertion of bizarre items besides traumatic memories might be functional to “impoverish” the negative charge of the experiences.

Introduction

Dreaming represents a fascinating experience linked to emotional processes so much so to be considered as a key to “access” in the human inner world (e.g., Freud's view; Freud, 1955 ). In the last decades, dream experience (DE) has been studied under the scientific perspective, defining dream recall as the retrieval of mental sleep elaboration with a different level of complexity and fragmentation, reported after awakenings (Fagioli, 2002 ).

For years, researchers considered Rapid Eye Movements (REM) sleep the privileged stage to dream (Desseilles et al., 2011 ) as long as different criteria to collect the reports were introduced (Foulkes, 1962 ). Actually, DE could be categorized as dream-like or thought-like on the basis of dream contents (Cavallero et al., 1992 ), including in the first the mentation related to higher emotionality and narrative contents and in the second, to more fragmented elements (Cipolli et al., 2017 ). Several studies confirmed that dreaming can occur both during REM and NREM sleep (Foulkes, 1962 ; Rechtschaffen et al., 1963 ; Monroe et al., 1965 ; Pivik and Foulkes, 1968 ; Taub, 1971 ; Cavallero et al., 1992 ; Antrobus et al., 1995 ; Stickgold et al., 2001 ). In particular, the DEs were obtained in up to 50% of cases upon awakening from NREM sleep, especially from stage 2 (Foulkes, 1962 ; Pivik and Foulkes, 1968 ; Nielsen, 2000 ) and REM sleep suppression pharmacologically-induced did not affect dream recall (Landolt et al., 2001 ; Oudiette et al., 2012 ).

Although the exclusive relation between REM sleep and dream has been overcome (Scarpelli et al., 2015a ), several studies point out that emotional and perceptually vivid contents are more frequent when reported upon awakenings from REM sleep (Foulkes et al., 1988 ; Nielsen et al., 1991 ; Merritt et al., 1994 ; Hobson et al., 2000 ; Kahn et al., 2002 ). More in general, REM sleep plays a pivotal role in the processing of emotional events and several studies showed that the consolidation of emotional memories occurs in this sleep stage (e.g., Lara-Carrasco et al., 2009 ; Nishida et al., 2009 ). In addition, experimental deprivation of REM sleep has been demonstrated to compromise the consolidation of emotional stimuli (Cartwright et al., 1975 ; Wagner et al., 2001 ; Lara-Carrasco et al., 2009 ; Spoormaker et al., 2014 ).

Dream contents including negative emotions (e.g., anxiety and fear) are more frequent than positive ones (Foulkes et al., 1988 ; Nielsen et al., 1991 ; Merritt et al., 1994 ; Fosse et al., 2001 ), and they are often related to waking-life experiences (Stickgold et al., 2001 ; Wamsley et al., 2010 ; Eichenlaub et al., 2017 ; Vallat et al., 2017 ). In this regard, the existing empirical evidence highlighted that the neural activation of emotional-limbic (Nir and Tononi, 2010 ) and reward systems (Perogamvros and Schwartz, 2012 ) during REM-DE contributes to the offline reprocessing of emotions and associative learning (Perogamvros et al., 2013 ).

Interestingly, clinical studies have also provided evidence on the potential interaction among DE, sleep alterations and affective disorders (Levin and Nielsen, 2007 ; Nielsen and Levin, 2007 ; Schredl, 2011 ). For instance, mood disturbances frequently appear along with sleep modifications involving REM sleep (Benca et al., 1992 , 1997 ; Walker and van der Helm, 2009 ). More directly, abundant dreams or nightmares are related to REM sleep abnormalities and psychiatric disorders (Cartwright et al., 2003 ; Modell et al., 2005 ; Agargun et al., 2007 ; Schredl et al., 2009 ; Sjöström et al., 2009 ; Marinova et al., 2014 ; Nakajima et al., 2014 ).

Taking into account the impossibility to directly access to the DE, most studies in the last decades were focused on the retrieval of dream contents upon awakenings (Scarpelli et al., 2015a ). Specifically, several investigations using spontaneous or provoked awakenings in the laboratory aimed to find the electrophysiological (EEG) patterns related to dream recall, considering it as a form of episodic-declarative memory (Mangiaruga et al., 2018 ).

In keeping with some earlier reviews (e.g., Revonsuo, 2000 ; Revonsuo et al., 2015 ), it could be hypothesized that DE may play a pivotal role in emotional encoding and regulation, nevertheless the specific function and the neural bases of REM-DEs were directly investigated by very few studies (De Gennaro et al., 2011 ; Eichenlaub et al., 2018 ; Vallat et al., 2018a ).

In light of the above, here we reviewed the main findings about neural bases of dreaming and the link between EEG correlates of DE and emotional processing, underlying that some evidence on sleep disorders characterized by a peculiar DE, especially occurring in REM sleep, may provide a better understanding on the functional role of dreaming and its potential applications in the clinical field.

Methodological Note

Studies were identified via PUBMED queries. Key search terms included:

- “Dreaming” and “REM sleep” and “Neuroimaging” in title/abstract (62 articles)
- “Dreaming” and “REM sleep” and “Emotional processing” (22 articles);
- “Dreaming” and “EEG” in title/abstract (686 articles);
- “Dreaming” and “PTSD” in title/abstract (450 articles);
- “Dreaming” and “Emotional Memories” in title/abstract (61 articles);
- “Dreaming” and “Narcolepsy” in title/abstract (128 articles);

We grouped the identified articles in the following categories:

Cognitive features, emotional aspects and EEG patterns of mental activity during REM sleep;
Dreaming and emotional process: (a) role of REM sleep in processing salient emotional waking life experiences; (b) EEG patterns implicated in REM sleep and emotional dreams; (c) associations among traumatic events and nightmares; (d) role of lucid dreams;
Dreaming in narcolepsy.

We focused on the role of emotions in REM sleep, excluding non-English articles. All the articles resulting from using this method and related to our focus were included. Following these criteria, we identified 88 publications which were estimated to be of interest for further examination.

Neural Bases of Dreaming and Emotional Processing

A large body of evidence showed that the regions implicated in emotional processes during wakefulness are also responsible for the neurophysiological background of REM sleep that can explain some qualitative features of DE (Maquet et al., 1996 ; Nir and Tononi, 2010 ; De Gennaro et al., 2011 , 2016 ; Eichenlaub et al., 2014 ; Vallat et al., 2018a ). In this section, we highlighted the commonalities between the neural bases of REM-DE and emotional processing.

Earlier studies on anatomical correlates of dream alterations by brain lesions studies confirmed the central role of specific cortical and subcortical areas in DE. The main findings point out that two specific cortical systems underlie dreaming. Firstly, a posterior system involves the Temporo-Parieto-Occipital Junction (TPJ) and lesions located in this region alter both waking mental imagery and sleep (Solms, 1997 , 2000 ). The anterior system includes the ventromedial prefrontal cortex (vmPFC) and the white matter surrounding the anterior horns of the lateral ventricles and its damage seems related to dream loss (Solms, 1997 , 2000 , 2011 ). It should be noted that many of the afferent and efferent fibers of these two systems are connected with the limbic system and the ventromesial frontal white matter seems to take a part in the interplay between basal forebrain and limbic structures (De Gennaro et al., 2012 , 2016 ).

More recently, human neuroimaging studies have gained a crucial role in dream research. Positron Emission Tomography (PET) and functional Magnetic Resonance Imaging (fMRI) were used especially in the measurement of functional changes in the brain during REM sleep. It has been demonstrated that the distribution of brain activity in REM sleep is not homogenous (Maquet, 2000 ; Nir and Tononi, 2010 ). Brain imaging studies found increased regional brain activity in the limbic and paralimbic structures, pontine tegmentum, thalamus and basal forebrain during REM sleep, as compared to wakefulness (Braun et al., 1997 , 1998 ; Nofzinger et al., 1997 ; Maquet, 2000 ) and NREM sleep (Braun et al., 1997 , 1998 ; Maquet et al., 2005 ). In addition, one of the first neuroimaging studies collecting dream report (Maquet et al., 1996 ) found a bilateral activation of the amygdala in subjects reporting DE upon awakenings from REM sleep, not providing any comparisons with non-recall conditions or awakenings from NREM sleep.

Moreover, remarkable activation of motor and premotor regions has been found in healthy subjects during REM sleep (Braun et al., 1997 ; Maquet et al., 2000 ; De Carli et al., 2016 ), albeit this sleep stage is characterized by muscular atonia thanks to the inhibition of spinal motor neurons by the ponto-bulbar reticular formation (Lai and Siegel, 1999 ). This seems in line with the observation that individuals affected by REM sleep behavior disorder (RBD) exhibit motor behaviors linked to their DE (Oudiette et al., 2009 ). Other brain areas are hypoactive during REM sleep compared to the waking state, such as the dorso-lateral PFC (dlPFC), precuneus, orbitofrontal cortex (OFC) and posterior cingulate gyrus (Maquet et al., 1996 ; Braun et al., 1997 ; Nofzinger et al., 1997 ). This evidence could explain the altered executive functions, time perception, and the lack of insight during DE (Desseilles et al., 2011 ).

Although it is well-known that dreaming is not restricted to REM sleep, some REM sleep features make it a privileged background for DE, especially characterized by high vividness, bizarreness and emotional load (Carr and Solomonova, 2018 ). In this respect, it should be underlined that most of the regions involved in emotional memory encoding and consolidation (Phelps and LeDoux, 2005 ; Armony, 2013 ) are highly activated during REM sleep. In particular, the higher activation of amygdaloid complexes, hippocampal formation and anterior cingulate cortex (ACC) in REM sleep than in wake and/or NREM sleep may explain the emotional intensity of DE reported upon REM sleep awakenings (Maquet et al., 1996 ; Braun et al., 1997 ; Nofzinger et al., 1997 ; Desseilles et al., 2011 ; Corsi-Cabrera et al., 2016 ). Some authors suggested that these structures may be responsible for the reprocessing and consolidation of emotional experiences during REM sleep (Hobson and Pace-Schott, 2002 ; van der Helm et al., 2011 ; Deliens et al., 2014 ).

According to the idea that DE play a role in the emotional processing, more recently awake fMRI measures revealed that subjects experiencing frequent fear during DE have a higher activation of mPFC and reduced activation in the insula, amygdala and midcingulate cortex when faced with aversive stimuli (Sterpenich et al., 2019 ). The results are consistent with the view that mPFC should exert an inhibitory control on fear expression by reducing amygdala activity (Phelps et al., 2004 ). A large amount of dream reports were collected at home and the presence of fear in DE has been considered as a trait-like factor of the participants (Sterpenich et al., 2019 ).

These results are consistent with the continuity hypothesis, namely the possibility that dreams and wakefulness shared similar mechanisms (Schredl, 2003 , 2009 ; Scarpelli et al., 2015a , b ; Mangiaruga et al., 2018 ; Sterpenich et al., 2019 ).

In fact, neuroimaging data in waking state have provided strong support for a crucial role of the aforementioned regions in emotional processing (Phan et al., 2004 ). It has been proposed that in the waking brain subcortical regions such as amygdala, nucleus accumbens, locus coeruleus, pulvinar, along with the ACC and OFC are involved in conscious and unconscious emotional processing (Morris et al., 1998 ; Vuilleumier et al., 2001 ; Kirov et al., 2012 ). Specifically, the unconscious perception of emotional stimuli has been related with the functional integrity of subcortical areas that receive an executive cortical feedback from the cortical network (e.g., dlPFC, OFC, and posterior cingulate cortex) only during wakefulness (Tamietto and De Gelder, 2010 ).

It is well-known that amygdala plays a pivotal role in emotional regulation. Several studies found that this structure is responsible for detecting, generating, and maintaining fear-related emotions (for a review see Phan et al., 2004 ). Moreover, the amygdala is important in the coordination of adequate responses to threat and danger and it has also been demonstrated that is critical also for response to stimuli that predict positive and negative future outcomes (Paton et al., 2006 ), allowing the organism to learn more about a stimulus and organize adaptive behavior (Maren, 2011 ). Specifically, the amygdala, thanks to the connections with the hippocampus, thalamus, mPFC, and ACC, is involved in control of the encoding and retrieval of affective memories and the physical expression of emotions during the waking state (Misane et al., 2005 ). Also, the hippocampus has an established role in emotional memory encoding and retrieval. Along with the amygdala, the hippocampal formation mediates the processing and execution of fear memories (Phelps, 2004 ).

Structural brain imaging approaches offer the possibility to focus on ultrastructural, anatomical measures and inter-individual variability associated with DE. This perspective allows researchers to overcome one of the intrinsic limitations of the study of dreams, concerning the difficult to exactly define the time-coupling between the sleep stages and the occurrence of DE. Neuroanatomical parameters provide a relatively stable measure to account for some trait-like features of DE. In this vein, the correlations between inter-individual differences in quantitative/qualitative features of DE reported by subjects and structural parameters of limbic areas were observed (De Gennaro et al., 2011 , 2016 ). Once again, the regions engaged in emotional encoding and consolidation showed a strong relationship with dream contents, consistently with the studies revealing that the structural characteristics of hippocampus and amygdala are associated with cognitive and emotional processing in waking tasks (Maguire et al., 2000 ; Bohbot et al., 2007 ; Iaria et al., 2008 ). Specifically, microstructural measures were related to the emotional load, bizarreness and vividness of DE reported. For what concerns emotional intensity, a relation was found between lower structural integrity of the left amygdala and decreased emotional load. Moreover, emotionality was linked to a smaller volume of the left hippocampus and larger volume of the right hippocampus. Also, dream contents characterized by high bizarreness were associated with smaller left amygdala, smaller right hippocampus and lower mean diffusivity of the right amygdala.

These observations were partially replicated on patients with Parkinson's Disease (PD), pointing that PD patients did not differ from healthy subjects with respect to sleep and dream characteristics or the neuroanatomical measures and confirming that vividness is related to the amygdalae and also the thickness of the left mPFC. It should be noted that, along with amygdala, mPFC plays a key role in the acquisition, consolidation and retrieval of fear memory and, specifically, modulates fear learning and extinction (Marek et al., 2013 ).

Moreover, this study on PD focused on the role of the dopaminergic system in DE. It has been found that higher dopamine agonist dosage was associated with qualitatively impoverished DE, as indicated by reduced bizarreness and emotional load levels (De Gennaro et al., 2016 ). It is worth noting that one of the main regulator of mesolimbic-dopamine network is the mPFC that makes direct and indirect connections to the amygdala and hippocampus (Patton et al., 2013 ). In other words, the recent findings on PD confirmed the evidence of an essential interplay between the mPFC and mesolimbic-dopamine system for dreaming, as previously showed by data from patients who underwent prefrontal leukotomy that stopped dreaming (Solms, 2011 ). In fact, in these patients, the ventromedial white matter containing dopaminergic projections to the frontal lobe were disconnected (Bradley et al., 1958 ). The importance of mPFC in dream processes has been confirmed in another study using PET (Eichenlaub et al., 2014 ). They revealed that subjects who recall more frequently their DE (i.e., High Recallers—HR) showed higher regional cerebral blood flow (rCBF) in the mPFC during REM sleep and wakefulness than “Low Recallers” (LR) along with higher rCBF in the TPJ during REM, NREM sleep and wakefulness (Eichenlaub et al., 2014 ). The structural data obtained by MRI from the same sample of Eichenlaub et al. ( 2014 ) and from another research (Vallat et al., 2018b ) were analyzed, confirming the relationship between brain anatomical structures and dream recall rate (Vallat et al., 2018a ). Specifically, the anatomical measures of the mPFC were significantly different between HR and LR (i.e., increased mPFC white-matter density in HR compared to LR was found). It should be underlined that mPFC is engaged in mind representations and evaluation (for a review, see Legrand and Ruby, 2009 ), that could have a crucial role in the emotional processing. More in general, it has been hypothesized that mPFC is related to cognitive aspects of emotional processing, such as appraisal/identification of emotion, attention to emotion, awareness and introspection (Phan et al., 2004 ). Furthermore, it has been demonstrated the involvement of this region in the social emotions processing (Ruby and Decety, 2004 ). Recently, it has been demonstrated that traumatic experiences and pathological memories are linked to abnormal interactions between hippocampus and mPFC that are responsible to reduced mnemonic ability and decreased emotional control (Maren et al., 2013 ; Jin and Maren, 2015 ).

Moreover, it is worth noting that lesion, imaging and stimulation data revealed that the TPJ is related to emotional processing and especially to the “theory of mind,” empathy and social cognition in the waking state (Saxe and Kanwisher, 2003 ; Young et al., 2010 ; Santiesteban et al., 2012 ; Van Overwalle and Vandekerckhove, 2013 ; Jeurissen et al., 2014 ). In particular, TPJ contributes to the mentalizing and emotional state inference/attribution (Donaldson et al., 2015 ; Ye et al., 2015 ; Biervoye et al., 2016 ).

Taken together, these findings revealed that, to some extent, the processes that regulate dreaming and emotional salience in DE share similar neural substrates of those controlling emotions during wakefulness. Moreover, in the light of the results by Eichenlaub et al. ( 2014 ), one might speculate that the high dream recaller may be particularly interested in their inner world (Ioannides et al., 2009 ), given that salience seems to have a pivotal role in dream recall, as evaluated in older individuals measuring episodic memory recall (for a review, see Mangiaruga et al., 2018 ).

Electrophysiological Correlates of Emotional Memories During REM Sleep and Wakefulness

In keeping with the neuroimaging studies exhibiting the relationship among REM sleep, dreaming and processing of emotional experience (De Gennaro et al., 2011 , 2016 ; Eichenlaub et al., 2014 ; Vallat et al., 2018a ), some investigations aimed to identify the sleep EEG correlates of emotional memory consolidation (Levin and Nielsen, 2007 ; Lara-Carrasco et al., 2009 ; Nishida et al., 2009 ; Walker, 2009 ; Walker and van der Helm, 2009 ; Spoormaker et al., 2014 ; Genzel et al., 2015 ; Hutchinson and Rathore, 2015 ; Sopp et al., 2017 , 2018 ). Although recent investigations showed that SWS plays a complementary role in this processing (Cairney et al., 2015 ; Payne et al., 2015 ; Yordanova et al., 2017 ), compelling evidence indicates that the potential EEG marker of emotional processes is the frontal theta activity (5–7 Hz) during REM sleep (Nishida et al., 2009 ; Prehn-Kristensen et al., 2013 ; Cowdin et al., 2014 ; Durrant et al., 2015 ; Seeley et al., 2016 ). For instance, Nishida et al. ( 2009 ) using a nap protocol, demonstrated that the prefrontal theta EEG activity during REM sleep was associated to a remarkable consolidation benefit for emotional memories rather than neutral memories. Moreover, the extent of emotional consolidation was significantly correlated with the proportion of REM sleep (Nishida et al., 2009 ). Also, the emotional consolidation of memory has been investigated in healthy and Attention-Deficit Hyperactivity disorder (ADHD) children compared to healthy adults (Prehn-Kristensen et al., 2013 ). Stimuli from the International Affective Picture System (IAPS) were presented before sleep and after morning awakening in order to test the emotional memory. The authors found that children with and without ADHD showed more slow oscillations (<1 Hz) during SWS and higher theta power during REM sleep. After merging all healthy subjects (children and adults), a correlation between emotional memory and prefrontal oscillations (i.e., theta and slow oscillations) was found. Conversely, ADHD displayed a negative correlation between performance and prefrontal oscillations (Prehn-Kristensen et al., 2013 ). Interestingly, this study confirmed the pivotal role of the theta band in emotional consolidation, underlying also that this relation is dysfunctional in the clinical group. Actually, this finding seems relevant since ADHD children have a compromised emotional regulation (Martel, 2009 ) and the marker during sleep of this deficit could be represented by an abnormal theta activity.

More recently, Sopp et al. ( 2017 ) showed that REM theta power correlated with enhanced retention of location memory for emotional images, consistent with the idea that REM theta oscillations reflect the reactivation of emotional mnestic traces.

The role of the REM theta oscillations in emotional memories was also replicated in a recent study that optogenetically silenced the GABAergic neurons in the medial septum causing the inhibition of memory-associated theta rhythm during REM sleep (Boyce et al., 2016 ). It has been found that silencing these neurons selectively during a REM critical window after learning impaired the performance fear-conditioned contextual memory and the novel object place recognition in the mice (Boyce et al., 2016 ).

It is worth noting that taken together, these results are in line with the waking EEG studies showing that the theta rhythm substantially correlates with episodic and emotional memory (Klimesch et al., 1996 ; Klimesch, 1999 ; Kirov et al., 2009 ; Uribe et al., 2011 ). It has been hypothesized that the theta rhythm is directly connected with some areas engaged in memory processing and, in particular, it represents an EEG marker of hippocampal activity (Klimesch, 1996 ; Cantero et al., 2003 ; Rutishauser et al., 2010 ) modulating neuronal changes in hippocampal formation and in neocortical structures (Mitchell et al., 2008 ). Humans EEG studies confirmed that the frontal theta EEG activity increases during memory tasks (for a review, see Hsieh and Ranganath, 2014 ) both in the encoding and retrieval stages of memory processing (Klimesch et al., 1997 , 2001 ; Klimesch, 1999 ; Mölle et al., 2002 ; Guderian and Düzel, 2005 ; Addante et al., 2011 ; Gruber et al., 2013 ; White et al., 2013 ). Interestingly, intracranial-EEG (iEEG) studies highlighted that theta oscillations play a pivotal role also in memory formation (Lega et al., 2012 ). In particular, a higher hippocampal-cortical theta phase coupling was reported in correspondence of optimal memory performance (Rutishauser et al., 2010 ). Furthermore, iEEG recordings demonstrated that theta oscillations modulate the interaction between PFC and the medial temporal lobe, confirming that both these areas could be involved in the recall processes (Anderson et al., 2010 ). More directly, magnetoencephalography (MEG) investigations showed a strong relation between theta activity and mPFC, suggesting that this area could generate theta oscillations (Asada et al., 1999 ; Ishii et al., 1999 ; Nishida et al., 2004 ).

Recently, it has been demonstrated that also the gamma activity during REM sleep represents a potential marker of emotional processing (van der Helm et al., 2011 ). For instance, an EEG-fMRI study tested the role of REM sleep in the behavioral and brain reactivity to recent waking emotional experiences comparing a group underwent PSG to a waking-group (van der Helm et al., 2011 ). The results revealed that: a) sleep decreases amygdala reactivity in response to previously encountered emotional experiences (presented by IAPS) as well as behavioral (subjective rating); b) this attenuation of emotional reactivity is related to mPFC connectivity and c) the reduced emotional reactivity is related to attenuated frontal gamma activity during REM sleep (van der Helm et al., 2011 ). In particular, the gamma activity could represent a marker of the suppression of central adrenergic neurotransmitters in REM sleep (also implicated in arousal and stress) involved in the encoding of emotional salient events along with activation in amygdala-hippocampal system (Walker and van der Helm, 2009 ; van der Helm et al., 2011 ). It has been proposed that the adrenergic reduction during REM sleep is essential to emotional regulation because of its role in defusing affective experiences and decreasing emotional intensity (Walker and van der Helm, 2009 ; van der Helm et al., 2011 ). For instance, the failure of this reduction during REM sleep has been found in anxiety disturbances associated to the presence of higher gamma activity, contributing to hyperarousal and amygdala reactivity (Etkin and Wager, 2007 ; Spoormaker and Montgomery, 2008 ; Walker and van der Helm, 2009 ). Quite surprisingly, this study did not find any effect on the theta band (van der Helm et al., 2011 ).

Also, Marshall et al. ( 2011 ) found that theta transcranial direct current stimulation (theta-tDCS) applied during REM sleep increases fast beta/gamma EEG oscillations. The theta-tDCS condition was associated with worse mood (i.e., as measured by Positive and Negative Affect Scale negative scores) on the morning after awakening from sleep, compared to sham (Marshall et al., 2011 ). In line with (van der Helm et al., 2011 ), this finding points to an indirect link between higher gamma during REM sleep and affective mental states. Moreover, the widespread increase in gamma activity with theta-tDCS provided evidence for the functional coupling between these two rhythms (Marshall et al., 2011 ).

It should be noted that waking EEG recordings found that theta and gamma oscillations can interact with each other (i.e., cross-frequency coupling) (Canolty et al., 2006 ; Cohen, 2008 ; Kramer et al., 2008 ; Penny et al., 2008 ; Young and Eggermont, 2009 ; Tort et al., 2010 ; Onslow et al., 2011 ; for a review see Lisman and Jensen, 2013 ). The theta/gamma coupling has been shown to be functionally relevant for long-term memory processes (Tort et al., 2009 ) contributing to the recall of stored information both in rats (Shirvalkar et al., 2010 ) and in humans (Friese et al., 2013 ). However, these studies revealed that the coupling occurs between the frontal theta and the posterior gamma oscillations (Friese et al., 2013 ). Little has been known on theta/gamma coupling in human emotional processing. A waking MEG study on emotional expressions found that both the theta and gamma activity occurring in overlapping areas of amygdala, visual cortex and frontal cortex (Luo et al., 2014 ). Interestingly, the frontal and visual cortical regions showed differences in the temporal profile of activity of these bands: the event-related synchronization peak appeared significantly later in the theta than in the gamma band (Luo et al., 2014 ). Bearing in mind these observations, it could be hypothesized that the prefrontal gamma could have a different functional role, concerning the reprocessing/depotentiation useful to decrease the emotional salience of recent waking experiences instead of a consolidation/retention of memory traces.

EEG Pattern of Dream Experiences

Dreaming could reflect the reactivation and consolidation of memories during sleep (Nielsen and Stenstrom, 2005 ; Wamsley and Stickgold, 2011 ). It is well-known that after the first peak in incorporation of waking memories into DE (1 day from the events) called “day-residue effect,” there is a second peak following the experience 6–7 days later, i.e., dream-lag effect (Nielsen et al., 2004 ; Blagrove et al., 2011 ; Eichenlaub et al., 2019 ). This delayed incorporation of daytime events has been found to hold for REM sleep dreams but not NREM-DE (Blagrove et al., 2011 ; van Rijn et al., 2015 ). Several findings supported that the incorporation of waking-life memories into dream contents represents this process of memory consolidation that allow the integration of the new mnestic traces in the older memories (Nielsen and Stenstrom, 2005 ). Although this fascinating perspective has given arise several hypotheses on the functional role of dreaming, very few studies have investigated the EEG correlates of incorporation in REM-DE, while the most of researches pointed to find the EEG pattern predicting the presence/absence of dream recall.

Multi-electrode recordings and quantitative analysis of the EEG signal showed that higher theta activity (5–8 Hz) during REM sleep is related to dream recall both in nocturnal sleep and naps (Marzano et al., 2011 ; Scarpelli et al., 2015b ). In addition, the reduction of the temporo-parietal alpha (8–11 Hz) activity was found before dream recall (Esposito et al., 2004 ; Marzano et al., 2011 ). Takeuchi et al. ( 2003 ) reported that during NREM sleep onset periods the dream recallers exhibited attenuated alpha and sigma power over the central area (Takeuchi et al., 2003 ). Nevertheless, they also found higher alpha and sigma activity localized in the central area during REM sleep onset periods in relation to dream recall (Takeuchi et al., 2003 ). Also, dream recall seems to be associated to increased alpha activity in correspondence of the occipital area, along with a lower frontal alpha power during REM sleep in a multi-nap protocol (Chellappa et al., 2011 ). It should be underlined that the alpha activity is one of the EEG bands most influenced by interindividual differences (De Gennaro et al., 2005 ) and this seems crucial when the experiment included between-subjects measures (Takeuchi et al., 2003 ; Esposito et al., 2004 ; Marzano et al., 2011 ). However, it should be also noted that the alpha, as well as theta band, play a pivotal role in the retrieval of the episodic mnestic traces during wakefulness as previous mentioned (Klimesch, 1999 ; Mölle et al., 2002 ). In the light of above, it has been hypothesized that the neural mechanisms responsible for dream recall resemble those for the encoding and the retrieval of episodic memories during wakefulness (De Gennaro et al., 2012 ; Scarpelli et al., 2015a ).

Once again, in line with the waking EEG studies, it has been reported that also gamma activity has some implications for the recall of DE (Siclari et al., 2017 ). In fact, Siclari et al. ( 2017 ) revealed that the enhancement of rapid frequencies (>25 Hz) during REM and NREM sleep is related to DE when compared with non-recall. In NREM sleep the high-frequency power increased over the parieto-occipital region along with a strong reduction of low-frequency power. Increased high-frequency power related to DE was observed in frontal and temporal areas during REM sleep. Also, it should be mentioned that DEs including “perceiving dimension” correlated with the high-frequency power over the parietal, occipital and temporal areas, while those including thoughts were related to the frontal regions (Siclari et al., 2017 ).

These patterns are also consistent with the indications obtained by brain lesions and neuroimaging findings in the field of dream research (Solms, 2000 ; Eichenlaub et al., 2014 ). It should be noted that a study by transcranial alternating current stimulation (tACS) revealed that the stimulation on the fronto-temporal area in the gamma band during REM sleep is related to lucid dreams (Voss et al., 2014 ). Albeit this study confirmed the crucial role of the gamma activity for dreaming, it is worth noting that the stimulated areas are different (i.e., fronto-temporal area instead of posterior region).

Interestingly, a very recent combined high-density EEG/-fMRI study identified the EEG activity underlining the DE including fear vs. DE without fear (Sterpenich et al., 2019 ). The results revealed that DE during REM sleep containing fear, as compared with DE without fear, was associated with decreased delta power over the insula and midcingulate cortex (Sterpenich et al., 2019 ). The same pattern, along with increased gamma power, was found in the right insula during NREM sleep in the case of DE containing fear (Sterpenich et al., 2019 ). The insula is involved in social-emotion experience and in visceral state (Chang et al., 2013 ), contributing in the integration of affective information (Shah et al., 2009 ; Sterpenich et al., 2019 ). Not surprisingly, also the activation of midcingulate during REM sleep is consistent with previous imaging data that found a critical activation in sensory and motor cortices (De Carli et al., 2016 ), since that it is a region involving the behavioral/motor responses to danger (Pereira et al., 2010 ). This activation could reflect an attempt to reactivate threatening situations with emotional and motor reactions that people experienced during wakefulness (Sterpenich et al., 2019 ).

Some findings provided compelling evidence on the relation between brain activity and dream contents (Dresler et al., 2011 ; Horikawa et al., 2013 ; Siclari et al., 2017 ; Sterpenich et al., 2019 ) by different approach (e.g., fMRI and machine learning; EEG source modeling; combined fMRI and near-infrared spectroscopy), while -to our knowledge- only few studies were aimed to directly investigated the EEG correlates of dreams containing day-residues, likely because of the difficulty to study the so-called “incorporation.” Dream contents from REM sleep showed a higher probability to include incorporated waking-life experiences (Schredl, 2006 ; Malinowski and Horton, 2014 ; Eichenlaub et al., 2018 ), especially when related to salient emotional events (Voss and Klimke, 2018 ). Specifically, Eichenlaub et al. ( 2018 ) tested the relationship between the theta activity during REM and incorporation of recent waking-life content in DE. They evaluated both emotional intensity and valence of waking-life experiences, assessing the relation with dream report collecting after REM sleep and SWS (Eichenlaub et al., 2018 ). This study showed that the frontal theta activity in both all and last REM sleep segments correlated to the number of references to waking experiences, identified by the participants into dream recall. Moreover, the reported dream contents contained a high amount of emotional events, irrespective of positive/negative valence (Eichenlaub et al., 2018 ). No correlations were found for SWS, confirming a strong link between REM sleep and emotional memories. Albeit previous studies showed the pivotal role of the frontal theta power for dream recall in healthy subjects (Marzano et al., 2011 ; Scarpelli et al., 2015b ), this study reported for the first time a direct link between the theta activity during REM sleep and the extent to which dream content is related to recent experiences. In this vein, it could be stated that dreaming reflects to some extent the emotional memory processing.

This perspective was also strengthened by a recent study investigating the activations of facial mimetic musculature during REM sleep as electrophysiological marker of emotional dreams (Rivera-García et al., 2018 ). The presence of specific facial expression during this stage can be interpreted as a Dream Enacting Behaviors (DEBs), namely the behavioral enactment of the emotional, verbal or motor components of complex dreams (Nielsen et al., 2009 ; Nir and Tononi, 2010 ). A growing body of literature suggests that DEBs are more frequent during nightmares or high emotionally intense dreams, providing a background to study the relation between DE and emotional processing (Nielsen et al., 2009 ; Rivera-García et al., 2018 ). Rivera-García et al. ( 2018 ) analyzed the facial EMG signals along with the standard PSG measures, finding that the activation of corrugator and zygomaticus facial muscles during REM sleep occurs when the incidence of emotional DE is higher (Rivera-García et al., 2018 ). Besides, this study -examining a wider range of emotions- confirmed that the peak rates in healthy population corresponded to the high negative emotional contents (Rivera-García et al., 2018 ). This evidence makes the analysis of DEBs a promising approach to study the emotional components of dreaming.

Insights From Sleep Disorders

Until now, we have discussed recent studies highlighting that REM sleep and some electrophysiological features REM-related may play a critical role in the emotional processes.

It should be emphasized that this evidence may afford insights for the translational research since that some dream and/or REM abnormalities represent the core symptoms of psychiatric and sleep disorders (Benca et al., 1992 , 1997 ; Harvey, 2008 ; Walker and van der Helm, 2009 ).

The relation among emotions, dreams and sleep disorders appear of special relevance in the context of Post-Traumatic Sleep Disorder (PTSD; Murkar and De Koninck, 2018 ). PTSD is characterized by hyperreactivity to emotional stimuli and an inability to extinguish traumatic memories (American Psychiatric Association, 2013 ) and sleep disturbances and recurrent nightmares are recognized as the hallmark of PTSD (Levin et al., 2010 ; Germain, 2013 ).

Taking this into account, the interaction of REM-depend learning and PTSD deserves interest (Breslau et al., 2004 ; Habukawa et al., 2007 ; Germain et al., 2008 ; Spoormaker and Montgomery, 2008 ; Yetkin et al., 2010 ; Germain, 2013 ; Pace-Schott et al., 2015 ). Specifically, PTSD patients report dreams with vivid images and negative emotions associated with the traumatic events (Germain, 2013 ). It should be considered that the percentage of REM sleep obtained following fear extinction was demonstrated to predict a decrease in autonomic arousal based on skin conductance (Spoormaker et al., 2010 ) and the disruption of REM sleep impaired extinction (Spoormaker et al., 2012 ). In this respect, it has been posited that REM sleep may amplify the altered function of the amygdala in PTSD patients, increasing dysphoric dreams (Germain et al., 2008 ). Moreover, also the idiopathic nightmares originating in early childhood results from dysfunctional hippocampal-amygdala-prefrontal circuit that controls fears memory formation and extinction (Nielsen and Levin, 2007 ; Marquis et al., 2017 ). In this view, the so-called “day-residue” and “dream-lag effect” (Nielsen and Stenstrom, 2005 ) seem relevant for the understanding of sleep-dependent memory consolidation and emotional balance in PTSD (Cipolli et al., 2017 ). Accordingly to the hypothesis that this phenomenon is an index of the memory consolidation (Nielsen and Stenstrom, 2005 ), in the context of PTSD, we argue that this process can fail for the emotional memories related to the traumatic events. In fact, dream-lag incorporation occurs more frequently in association to interpersonal problem-solving and are most evident among individuals who report that their DE affects thoughts and feelings during the waking state (Nielsen and Powell, 1992 ; Kuiken, 2009 ). Interestingly, Powell et al. ( 1993 ) observed that events characterized by high emotional load appear into dream recall for the first 3 days following the event and then again after a delay of from 6 to 7 days. Moreover, (Domhoff, 1996 ) evidenced that stress-related dream contents may recur over periods of time lasting from days to years. Hence, dreams can represent a reactivation of waking-life experiences with the function of re-processed the conflictual events and their negative emotional tone (Walker and van der Helm, 2009 ). On the one hand, it can be speculated that REM sleep can provide the electrophysiological background to allow the fade of the negative emotional charge of autobiographical memories faster than a positive one (Ritchie and Skowronski, 2008 ). On the other hand, when REM abnormalities occur this functional emotional process fails. In this view, it has been recently demonstrated that negative waking-life experiences incorporated into dreams were characterized by less emotional intensity when reported as dream report (Vallat et al., 2017 ), accordingly to the idea that dreams foster the emotional regulation reducing the emotional tone of waking-life memories.

Interestingly, a recent study investigated EEG activity in frequent nightmares recallers and controls, observing that higher slow theta (2–5 Hz) activity over frontal and central areas characterized the nightmares group especially during REM sleep compared to controls (Marquis et al., 2017 ). The results support the idea that REM frontal theta activity also modulates abnormal dreams (i.e., nightmares) in keeping with the evidence that the prefrontal theta activity is related with negatively balanced dreaming during REM sleep (Hebert et al., 2015 ). Partly, this appears also consistent with the results on EEG correlates of dream recall in healthy subjects (Marzano et al., 2011 ; Scarpelli et al., 2015b ; Eichenlaub et al., 2018 ). In addition, the prefrontal theta rhythm seems to be related to emotional coping strategy in trauma-exposed subjects that had never developed PTSD, since that these resilient individuals showed higher theta than clinical sample (Cowdin et al., 2014 ). It is worth noting that DE were not collected in the latter study, not allowing to disentangle if the adaptive role of theta activity is related only to REM sleep per se or to some kind of mental sleep activity.

Along with PTSD, also narcolepsy is characterized by a peculiar DE (Schredl, 1998 ). The study of DE and its relation with emotional processes in narcoleptic patients can deserve attention since that: a) The cataplexy -one of the main narcoleptic symptoms- is generally triggered by intense emotions (De Zambotti et al., 2014 ); b) The impairment of the limbic system has been repeatedly found in narcoleptic patients (e.g., Mignot et al., 2002 ; Joo et al., 2005 ; Hong et al., 2006 ; Schwartz et al., 2008 ; Meletti et al., 2015 ). Narcoleptic patients often report an abundant production of vivid, bizarre and frightening dreams (Schredl, 2008 ) with a remarkable amount of aggressive themes (Bourguignon, 1976 ). Investigations on narcoleptic subjects showed higher negatively toned and bizarre dreams along with more terrifying contents than insomnia patients (Mangiaruga et al., 2018 ). Some authors stated that narcolepsy emphasized the emotional items of their REM dreams as results of the compromised neurobiological system underling the cognitive-emotional functions (Lee et al., 1993 ). Specifically, it has been found that DE included more anxiety/fear and more bizarre and vivid contents (Fosse, 2000 ; Fosse et al., 2002 ).

Also, nightmares seem to occur with a certain frequency in this population (Schredl, 1998 ; Schredl et al., 2012 ; Pisko et al., 2014 ), likely because of daytime stress due to the impairments caused by narcolepsy (Rak et al., 2015 ). It has been found that the percentage of nightmares in the narcoleptic group was 33% (Pisko et al., 2014 ), while the prevalence of nightmares in general population was around 5% (Li et al., 2010 ; Sandman et al., 2013 ). Conversely, Meaidi et al. ( 2016 ) found no differences in emotional dream contents and in the frequency of nightmares between narcoleptic and healthy subjects. This study showed a greater amount of lucid dreams in narcoleptic than controls (Meaidi et al., 2016 ). Albeit conflicting results are reported on this issue (Vogel, 1976 ; Wamsley et al., 2014 ), according to recent studies (Rak et al., 2015 ; Meaidi et al., 2016 ) it could be hypothesized that the increase in lucid dreaming in narcoleptic patients compared to controls can explain the low incidence of nightmares in this clinical group. Namely, lucid dreams may be considered as a sort of coping strategies to deal with the negative emotional contents of DE. In fact, narcoleptic patients who had experience with lucid dreaming felt that dream lucidity provides relief during nightmares (Rak et al., 2015 ). In other words, dream lucidity led dreamers to affect oneiric contents, also altering their emotional negative charge (Dresler et al., 2011 , 2014 ).

In line with this evidence, some studies suggested that lucid dreams could be useful as intervention for nightmare disorders (Zadra and Pihl, 1997 ; Spoormaker et al., 2003 ; Spoormaker and Van den Bout, 2006 ). Bearing in mind that the methods to induce lucid dreaming often including the promotion of cortical arousal (Stumbrys et al., 2012 ; Voss et al., 2014 ), it may be hypothesized that some sleep narcoleptic features such as fragmented sleep, a short sleep latency and sleep onset REM periods, could facilitate lucid dreams (Rak et al., 2015 ). In fact, the application of the wake-up-back-to-bed technique (i.e., subjects are awakened in the early morning hours and go back to sleep after a period of wakefulness; LaBerge et al., 1994 ; Stumbrys et al., 2012 ) has proved to be effective in inducing lucid dreaming in healthy individuals (Erlacher, 2010 ). It should be noted, the notion that higher cortical desynchronization and fragmented sleep promote dreams is not new in healthy subjects (Koulack and Goodenough, 1976 ; Scarpelli et al., 2017 ; Siclari et al., 2017 ) as well as in nightmare sufferers (Simor et al., 2013 ) and in narcoleptic patients (Dodet et al., 2015 ; D'Atri et al., 2019 ). Specifically, in narcoleptics the successful dream recall upon awakenings was related to higher cortical arousal over parietal regions compared to unsuccessful dream recall, consistently with the findings on healthy individuals (Siclari et al., 2017 ).

Interestingly, the idea that the awareness of our own dream contents and the possibility of altering them may be beneficial for nightmare sufferers has been proposed by earlier studies (Kellner et al., 1992 ; Neidhardt et al., 1992 ; Krakow et al., 2001 ). Specifically, over 20 years ago the so-called “Imagery rehearsal treatment (IRT)” was introduced (Kellner et al., 1992 ). IRT is a cognitive-behavioral technique that effectively reduces chronic nightmares within 6–12 weeks of treatment (Marks, 1978 ; Kellner et al., 1992 ; Neidhardt et al., 1992 ; Krakow et al., 1995 , 2001 , 2002 ; Forbes et al., 2001 ; Germain et al., 2004 ). This method consists of the imaginal rehearsal of a new dream that erased distressing contents, altering the original scenario of nightmare (Kellner et al., 1992 ). The nightmare sufferers learn to manage the original scenes, creating a less frightened ending and becoming able to include in the new dreams mastery elements, such as the emotional items aimed to change the overall dream affect or emotional reactions to specific dream characters, events or settings (Germain et al., 2004 ). However, to our knowledge no studies on neurophysiological correlates of this emotional/traumatic memories re-processing are available.

Concluding Remarks

Here, we outlined that dreaming during REM sleep may have a pivotal role in the emotional regulation and emotional memory consolidation, accordingly with some previous works (e.g., Cartwright et al., 1998 ; Desseilles et al., 2011 ). The current literature does not provide a homogeneous framework on the link between dreaming, emotional processes and neurobiological correlates, albeit remarkable insights from neuroimaging, electrophysiological data and clinical sample led to some final considerations on the functional role of DE that both in healthy and clinical sample serves to affect the inner well-being.

Firstly, we highlighted that emotional regulation and dreaming share similar neurobiological bases suggesting that the amygdala, hippocampus and mPFC operate in a sort of continuum between wakefulness and REM sleep (De Gennaro et al., 2011 , 2016 ; Eichenlaub et al., 2014 ; Vallat et al., 2018a ; Sterpenich et al., 2019 ).

DE could be considered as a reactivation of waking-life memories and during REM sleep this “re-play” concerns especially highly emotional contents (Cipolli et al., 2017 ). However, dreaming is a product of an “internal and virtual fabrication” and not always the memory sources are easily identified during wakefulness, so considering DE only as the replay of past experiences may seem reductive (Kirov, 2013 ; Hobson et al., 2014 ). Specifically, Hobson et al. ( 2014 ) introduced the notion that dreaming plays a pivotal role in enhancing the possibility to create a “virtual world” during sleep that helps to generate more efficient predictions during waking. Hence, dreams not only can contribute to the consolidation of memories with a great emotional load, but it can also represent a mechanism to simulate the real world as a sort of problem-solving based on emotional coping strategies, according to Revonsuo ( 2000 ) and Revonsuo et al. ( 2015 ).

The studies on dysphoric dreams seem to provide support in favor of this view. In fact, promoting the rehearsal of frightening contents to change them is a promising method to treat nightmares (Kellner et al., 1992 ). In other words, dreams can defuse emotional traumatic memories when the emotional regulation and the fear extinction mechanism are compromised by traumatic and frightening events, such as in the case of PTSD (Germain et al., 2004 ), providing the possibility to create a new scenario enriched with mastery elements (Germain et al., 2004 ). It should be noted that a previous work suggested that the inclusion of bizarre items in the DE may provide a de-contextualization of experiences to promote a better assimilation of salient emotional contents in the existing memories (Horton and Malinowski, 2015 ). However, it could be hypothesized that the insert of bizarre items beside to traumatic memories might be functional to “impoverish” the negative charge of the experiences.

More recently, from a neurophysiological perspective it has been proposed that the desynchronized neuronal activity in REM sleep, along with the pattern of brain activation (Maquet, 2000 ) allows the generation of new associative cell assemblies in highly activated regions such as the hippocampus (Voss and Klimke, 2018 ). In particular, this model assumes that the bizarreness and vividness dream contents mirror this involuntary associative activity involving the formation of new cell assemblies due to the down-regulated activity in the frontal lobes during REM sleep (Voss and Klimke, 2018 ).

Beyond these hypotheses, we underlined that the research on EEG correlates of the presence/absence of DE (Marzano et al., 2011 ; Scarpelli et al., 2015b ) and the results on EEG pattern related to the incorporated memories (Eichenlaub et al., 2018 ) converged to assign a crucial role of REM theta oscillations in this emotional re-processing. In particular, the theta activity is involved in memory processes during REM sleep as well as during waking state (Klimesch et al., 1996 ; Marzano et al., 2011 ) in line with the continuity hypothesis (Schredl, 2003 , 2009 ; Scarpelli et al., 2015a , b ; Mangiaruga et al., 2018 ). Also, both posterior and frontal gamma activity seems to be related to emotional processes and dream recall and -interestingly- this band is related to lucid dreams (Voss et al., 2014 ; Dodet et al., 2015 ), that are associated with an attenuation of nightmares (Rak et al., 2015 ). Moreover, the frontal gamma activity seems to have a role in decreasing the amygdala reactivity (van der Helm et al., 2011 ).

Interestingly, similar EEG correlates of DE have been found in clinical samples when nightmares or dreams occur. Once again, the theta activity (Marquis et al., 2017 ) and the EEG characterized by high cortical activation (Simor et al., 2013 ; D'Atri et al., 2019 ) appear to be crucial in the production and retrieval of DE.

Bearing in mind all of these considerations, some limitations should be mentioned on the hypothesis that REM-DE plays a key role in emotional processing. Firstly, we have highlighted that very little evidence so far is available on a memory function of REM-dreaming per se and for this reason it could be challenging to distinguish the role of REM sleep from those of REM-DE in emotional processing. Actually, the role of REM sleep in the mood regulation is somehow controversial since several studies found that this stage has a depressant effect (Palagini et al., 2013 ). For instance, awakenings from REM sleep are associated to higher scores in the Hamilton Rating Scale for Depression (McNamara et al., 2010 ), and the increase in REM density (Riemann et al., 1994 ; Wurts and Edgar, 2000 ) with higher EEG fast-frequencies (Riemann et al., 1994 ) have been recognized as the main neurophysiological correlates of depression during sleep. On the one hand, sleep deprivation has been showed beneficial in patients with major depression (Gillin et al., 2001 ). On the other hand, sleep loss is also related to a compromised consolidation of negative emotional memories (Sterpenich et al., 2007 ), and this beneficial effect on the mood is linked with emotional lability and inappropriate emotional reactivity in healthy adults under sleep deprivation (Horne, 1988 ; Dahl, 1996 ; Gujar et al., 2011 ). Although disentangling the issue is out of our purpose, undoubtedly, REM sleep alterations are responsible of emotional imbalance and the maintenance of REM sleep promotes adaptive emotional responses during waking life (Walker and van der Helm, 2009 ). In this view, dreams during REM sleep may help emotional regulation, especially when negative affects are inserted in DE, helping a sort of “exposure” and desensitization as in the case of the fear extinction (Levin and Nielsen, 2007 ; Pace-Schott et al., 2012 ; Menz et al., 2013 ).

Furthermore, albeit the dream reports from NREM sleep are often “thought-like” (Hobson et al., 2000 ), some traces of emotions reflecting the individual's concerns can be observed also during the SWS, as in the case of pavor nocturnus or night terrors (Gottesmann, 2010 ; Kirov et al., 2012 ; Castelnovo et al., 2016 ). NREM as well as REM sleep is involved in the memory replay (Diekelmann and Born, 2010 ; Oudiette and Paller, 2013 ), since that both slow oscillations and sleep spindle have been reported in association with memory consolidation (especially declarative) and synaptic plasticity processes (Diekelmann and Born, 2010 ).

Hence, we do not wish to exclude that also DE during NREM sleep can be “dream-like” and emotional. We emphasize that dream data revealed that affective items are generally higher in REM than in NREM-DE (Hobson et al., 2000 ) and that the specific physiological background of REM sleep -in continuity with the waking state- may provide a permissive condition for emotional information to be reorganized.

Furthermore, there are important between-subjects and within-subjects variability (Scarpelli et al., 2015a ) in recalling dreams. Although the state- and trait-like factors affect the presence/absence of DE, we underlined that the successful DE with high emotional load is observed in the most of cases when clinical samples are analyzed. Along this vein, the DE features may provide some information on the disease process, as in the case of PTSD. Also, taking into account that specific microstructural features have been related to DE, further examination of the EEG pattern in healthy and clinical sample of dreaming may follow two steps: (a) protocols collecting DE in healthy subjects with EEG at high spatial (i.e., high-density EEG) resolution should be carried out in order to replicate the previous findings on the relationship among specific oscillations (gamma; beta; theta; delta) and the dreaming features (e.g., Scarpelli et al., 2015b ; Siclari et al., 2017 ). Within-subjects design, a control of homeostatic and circadian factors as well as technique to better distinguish rhythmic from EEG background signal (e.g., Better Oscillation method; Kaplan et al., 2001 ) should be used; (b) Studies on EEG correlates of DE in sleep disorders where dreaming is related to the symptoms should be carried out. Also, longitudinal data could be collected to observe the potential changes in the EEG pattern and dream contents.

In particular, the findings discussed point out that both the theta and gamma EEG activities are essential for dreaming and emotional processes. From a translational perspective, it could be interesting to investigate how these frequency bands modulate emotional and traumatic memories incorporated in dreaming. In fact, it could be useful to implement new methods to change the dream content in something of neutral, not disturbing or positive for patients who suffer from nightmares. For example, the tACS techniques allow eliciting lucid dreams through a frontal gamma activity stimulation (Voss et al., 2014 ). In this perspective, considering lucid dreams as a sort of coping strategies to deal with the negative emotional contents of DE, it could be promising as intervention for nightmare disorder (Zadra and Pihl, 1997 ; Spoormaker et al., 2003 ; Spoormaker and Van den Bout, 2006 ).

Finally, considering that dreaming is an irregular phenomenon and not always observable, it should be considered that a new frontier to investigate more directly the relationship between dreaming and emotions is represented by the DEB (Rivera-García et al., 2018 ) that can be a viable access to dreams, overcoming the intrinsic difficulty to study this phenomenon (Arnulf, 2012 ; Alfonsi et al., 2019 ). More in general, the parasomnias as RBD may be considered a privileged model to study both REM abnormalities and sleep mentation with high emotional load since that these manifestations are often characterized by aggressiveness and negative emotions.

Author Contributions

LD and SS made substantial contributions to the conception and design of the work. LD, SS, CB, AD, and MG contributed by drafting the work and revising it critically for important intellectual content, responsible for the final approval of the version to be published, and agreed to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Conflict of Interest Statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Acknowledgments

This work was supported by a grant to SS from BIAL Foundation (grant 2016/2017 No. 32/16).

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Dream Studies Portal

Dream research, lucid dreaming, and consciousness studies

Calvin Hall and the Cognitive Theory of Dreaming

By Ryan Hurd

Any survey of modern dream research must include Calvin Hall (1909-1985). Hall was a behavioral psychologist who explored the cognitive dimensions of dreaming. His work began before the discovery of REM sleep, so little was known about the biology of sleep and dreams. Hall drew worldwide attention for his cognitive theory of dreaming , which was among the first scientific theories of dream interpretation based on quantitative analysis… rather than wishful thinking.

Dreams Images are the Embodiment of Thought

Central to Hall’s cognitive theory is that dreams are thoughts displayed in the mind’s private theater as visual concepts. Like Jung, Hall dismissed the Freudian notion that dreams are trying to cover something up. In his classic work The Meaning of Dreams (1966), Hall writes, “The images of a dream are the concrete embodiments of the dreamer’s thoughts; these images give visual expression to that which is invisible, namely, conceptions.” (p. 95).

So dreams reveal the structure of how we envision our lives, a display that is clearly valuable for anyone who remembers and studies their own dreams.

The Way We See the World

After studying thousands of dreams collected from his students and from around the world, Hall suggested that the main cognitive structures that dreams reveal include:

conceptions of self (how we appear to ourselves, the roles we play in life)
conceptions of others (the people in our lives and how we react to their needs
conceptions of the world (our environment: is it a barren wasteland or a nurturing place?)
conceptions of penalties (how we view the Man. What is allowed? What is forbidden?)
conceptions of conflict (our inner discord and how we struggle with resolving it).

As a behavioral psychologist, Hall believed these conceptions are antecedents to our behavior in the waking world. They’re like maps to our actions, and “with these maps we are able to follow the course of man’s behavior, to understand why he selects one road rather than another, to anticipate the difficulties and obstacles he will encounter, and to predict his destinations.” (as qtd in Van De Castle, p. 190)

Content Analysis: the Hall-Van de Castle Scale

Hall’s work is still widely cited today, but his greatest legacy is the system of dream content analysis he developed with psychologist Robert Van De Castle in the 1960s.

Known as the Hall Van De Castle scale, this quantitative system scores a dream report with 16 empirical scales. Some scales are settings, objects, people, animals, and mythological creatures. You know, the sort of things you see walking down the street on any given day. (If you haven’t seen any chimeras or griffins recently, then you’re working too much). Other scales include emotions, sexual content, aggression, etc. .

The value of the project is that there are now hundreds of thousands of dreams measured using the HVdC system, creating a “baseline” for normal dreaming cognition. So researchers can add dreams from special interest groups (children, Vietnam vets, Armenian students) to measure their profiles against the norm. (see Figure 1 for an example of the possibilities)

This innovation is a huge milestone in the scientific study of dreams. Now researchers can easily get a snapshot of dreaming cognition that is measurable, quantitative, and statistically significant. Besides psychologists, this scale is still used widely today by sociologists and anthropologists.

And thanks to Hall’s student Bill Domhoff, now a powerful dream research figure in his own right, much of Hall and Van De Castle’s database is available online .

Dream content has coherent meaning—that is the main message behind Hall’s work with dreams. This view later came under fire by the controversial work of neuroscientist Allan Hobson , who implied that dreams may be nothing more than images stitched together from random brain pulses. This rift may be the central conflict in dream studies today.

Reader Interactions

December 4, 2009 at 10:16 pm

Thanks for the thorough presentation of Hall’s theory, Ryan. I’ve never encountered his name before. I’m a little bit perplexed though as to why a behavioral psychologist, like Hall, got involved in psychoanalytic research. I guess there’s not much difference between the two fields at that time. Anyway, I think his system of content analysis is indeed useful in providing quantitative data for the investigation of dreams knowing that the latter is filled with abstractions and that subjects who report their dreams may find it difficult to remove subjective interpretations while trying to recall dreams from memory.

December 6, 2009 at 8:53 pm

Ryhen, you’re right about the issues with dream recall and after-the-fact revision… that is actually one of the central criticisms of Hall and Van de Castle’s system.

That’s why it’s important to understand that dream researchers don’t study dreams per say… we study dream reports. a dream is actually a memory, and memory is highly unpredictable. the critique isn’t devastating to the enterprise of dream studies, but certainly a dangerous pothole along the path.

December 8, 2009 at 4:00 pm

The story, as I heard it from Bill Domhoff, was that Hall was originally trained as a behaviorist in the 30’s and 40’s, the heyday of that psychological system. He focused on the study of anxiety in lab rats, which he measured by giving them mild electric shocks and then counting the resulting number of feces (which are apparently an accurate index of a rat’s level of fear). I don’t know why Hall shifted toward psychoanalysis and cognitive psychology, but I find it strangely appropriate that his approach to dream content analysis has its roots in counting rat turds.

December 8, 2009 at 5:48 pm

Kelly, thanks for coming by and also for the behaviorist scoop on Hall!

December 12, 2009 at 6:54 am

Great overview of an important perspective on dreamwork. I’m very opposed to a purely materialistic “random neural firings” hypothesis about dreams.

January 31, 2010 at 11:15 pm

Some nits for you Calvin Hall’s name does not have Jr. in the title Our Dreaming Mind was published in 1994 not 93 Domhoff’s book on Finding Meaning etc was published in 1996, not 97

February 1, 2010 at 1:07 pm

thanks, Bob, for stopping by! I’ll pick those nits.

February 9, 2010 at 10:30 am

Thanks for your overview on the cognitive theory of dreams. I’m writting a research paper on dreams where I’m looking at this theory and Freud’s theory and my argument is that the cognitive theory provides the most clarity in understanding our dreams. I was wondering if you know of any study a psychologist has conducted where he has concluded that a particular dream supports the cognitive dream theory,

I have looked into Domhoff’s dreambank.net website, and found one study that I think I may be able to use in my paper;however, I was just curious to see whether you’ve come across any such study

Thank you so much for your updates on your blog, I’d appreciate a response as soon as you can

Thanks! Tina

April 16, 2010 at 10:41 am

hi Tania am not sure how late this feedback but ..try looking into Deirdre Barrett work she has numerous books and articles on that part she is the chief editor of Dreaming Journal hope this helps. Star

April 16, 2010 at 10:52 am

thanks Star — and sorry Tina — another comment that got by my radar. in general the studies that support cognitive theory are by the researchers who use cognitive theory. same goes for Freudian theory, Jungian theory, etc. There is no final authority on the meaning of dreams when it comes down to individual dreams. in my opinion — and many dream workers — the final authority is YOU. what feels right? what can you learn? studying dreaming like all cognitive artifacts is a study in meaning-making, and nobody can tell you what something means, they can only lead the way…

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The Science of Sleep: Regulating Emotions and the 24 Hour Mind

Even if we often think of sleeping as ‘switching off’, it’s a complex state during which a lot of important things occur in our bodies. In particular, dreams are vital for helping our brains to process emotions and encode new learning.

“Memory is never a precise duplicate of the original; instead, it is a continuing act of creation..” — Rosalind Cartwright

Rosalind Cartwright is one of the leading sleep researchers in the world. Her unofficial title is Queen of Dreams.

In The Twenty-four Hour Mind: The Role of Sleep and Dreaming in Our Emotional Lives , she looks back on the progress of sleep research and reminds us there is much left in the black box of sleep that we have yet to shine light on.

In the introduction she underscores the elusive nature of sleep:

The idea that sleep is good for us, beneficial to both mind and body, lies behind the classic advice from the busy physician: “Take two aspirins and call me in the morning.” But the meaning of this message is somewhat ambiguous. Will a night’s sleep plus the aspirin be of help no matter what ails us, or does the doctor himself need a night’s sleep before he is able to dispense more specific advice? In either case, the presumption is that there is some healing power in sleep for the patient or better insight into the diagnosis for the doctor, and that the overnight delay allows time for one or both of these natural processes to take place. Sometimes this happens, but unfortunately sometimes it does not. Sometimes it is sleep itself that is the problem.

Cartwright underscores that our brains like to run on “automatic pilot” mode, which is one of the reasons that getting better at things requires concentrated and focused effort. She explains:

We do not always use our highest mental abilities, but instead run on what we could call “automatic pilot”; once learned, many of our daily cognitive behaviors are directed by habit, those already-formed points of view, attitudes, and schemas that in part make us who we are. The formation of these habits frees us to use our highest mental processes for those special instances when a prepared response will not do, when circumstances change and attention must be paid, choices made or a new response developed. The result is that much of our baseline thoughts and behavior operate unconsciously.

Relating this back to dreams, and one of the more fascinating parts of Cartwright’s research, is the role sleep and dreams play in regulating emotions. She explains:

When emotions evoked by a waking experience are strong, or more often were under-attended at the time they occurred, they may not be fully resolved by nighttime. In other words, it may take us a while to come to terms with strong or neglected emotions. If, during the day, some event challenges a basic, habitual way in which we think about ourselves (such as the comment from a friend, “Aren’t you putting on weight?”) it may be a threat to our self-concepts. It will probably be brushed off at the time, but that question, along with its emotional baggage, will be carried forward in our minds into sleep. Nowadays, researchers do not stop our investigations at the border of sleep but continue to trace mental activity from the beginning of sleep on into dreaming. All day, the conscious mind goes about its work planning, remembering, and choosing, or just keeping the shop running as usual. On balance, we humans are more action oriented by day. We stay busy doing, but in the inaction of sleep we turn inward to review and evaluate the implications of our day, and the input of those new perceptions, learnings, and—most important—emotions about what we have experienced. What we experience as a dream is the result of our brain’s effort to match recent, emotion-evoking events to other similar experiences already stored in long-term memory. One purpose of this sleep-related matching process, this putting of similar memory experiences together, is to defuse the impact of those feelings that might otherwise linger and disrupt our moods and behaviors the next day. The various ways in which this extraordinary mind of ours works—the top-level rational thinking and executive deciding functions, the middle management of routine habits of thought, and the emotional relating and updating of the organized schemas of our self-concept—are not isolated from each other. They interact. The emotional aspect, which is often not consciously recognized, drives the not-conscious mental activity of sleep.

Later in the book, she writes more about how dreams regulate emotions:

Despite differences in terminology, all the contemporary theories of dreaming have a common thread — they all emphasize that dreams are not about prosaic themes, not about reading, writing, and arithmetic, but about emotion, or what psychologists refer to as affect. What is carried forward from waking hours into sleep are recent experiences that have an emotional component, often those that were negative in tone but not noticed at the time or not fully resolved. One proposed purpose of dreaming, of what dreaming accomplishes (known as the mood regulatory function of dreams theory) is that dreaming modulates disturbances in emotion, regulating those that are troublesome. My research, as well as that of other investigators in this country and abroad, supports this theory. Studies show that negative mood is down-regulated overnight. How this is accomplished has had less attention. I propose that when some disturbing waking experience is reactivated in sleep and carried forward into REM, where it is matched by similarity in feeling to earlier memories, a network of older associations is stimulated and is displayed as a sequence of compound images that we experience as dreams. This melding of new and old memory fragments modifies the network of emotional self-defining memories, and thus updates the organizational picture we hold of “who I am and what is good for me and what is not.” In this way, dreaming diffuses the emotional charge of the event and so prepares the sleeper to wake ready to see things in a more positive light, to make a fresh start. This does not always happen over a single night; sometimes a big reorganization of the emotional perspective of our self-concept must be made—from wife to widow or married to single, say, and this may take many nights. We must look for dream changes within the night and over time across nights to detect whether a productive change is under way. In very broad strokes, this is the definition of the mood-regulatory function of dreaming, one basic to the new model of the twenty-four hour mind I am proposing.

In another fascinating part of her research, Cartwright outlines the role of sleep in skill enhancement. In short, “sleeping on it” is wise advice.

Think back to “take two aspirins and call me in the morning.” Want to improve your golf stroke? Concentrate on it before sleeping. An interval of sleep has been proven to bestow a real benefit for both laboratory animals and humans when they are tested on many different types of newly learned tasks. You will remember more items or make fewer mistakes if you have had a period of sleep between learning something new and the test of your ability to recall it later than you would if you spent the same amount of time awake.

Most researchers agree “with the overall conclusion that one of the ways sleep works is by enhancing the memory of important bits of new information and clearing out unnecessary or competing bits, and then passing the good bits on to be integrated into existing memory circuits.” This happens in two steps.

The first is in early NREM sleep when the brain circuits that were active while we were learning something new, a motor skill, say, or a new language, are reactivated and stay active until REM sleep occurs. In REM sleep, these new bits of information are then matched to older related memories already stored in long-term memory networks. This causes the new learning to stick (to be consolidated) and to remain accessible for when we need it later in waking.

As for the effect of alcohol has before sleep, Carlyle Smith, a Canadian Psychologist, found that it reduces memory formation, “reducing the number of rapid eye movements” in REM sleep. The eye movements, similar to the ones we make while reading, are how we do scanning of visual information.

The mind is active 24 hours a day:

If the mind is truly working continuously, during all 24 hours of the day, it is not in its conscious mode during the time spent asleep. That time belongs to the unconscious. In waking, the two types of cognition, conscious and unconscious, are working sometimes in parallel, but also often interacting. They may alternate, depending on our focus of attention and the presence of an explicit goal. If we get bored or sleepy, we can slip into a third mode of thought, daydreaming. These thoughts can be recalled when we return to conscious thinking, which is not generally true of unconscious cognition unless we are caught in the act in the sleep lab. This third in-between state is variously called the preconscious or subconscious, and has been studied in a few investigations of what is going on in the mind during the transition before sleep onset.

Toward the end, Cartwright explores the role of sleep.

[I]n good sleepers, the mind is continuously active, reviewing experience from yesterday, sorting which new information is relevant and important to save due to its emotional saliency. Dreams are not without sense, nor are they best understood to be expressions of infantile wishes. They are the result of the interconnectedness of new experience with that already stored in memory networks. But memory is never a precise duplicate of the original; instead, it is a continuing act of creation. Dream images are the product of that creation. They are formed by pattern recognition between some current emotionally valued experience matching the condensed representation of similarly toned memories. Networks of these become our familiar style of thinking, which gives our behavior continuity and us a coherent sense of who we are. Thus, dream dimensions are elements of the schemas, and both represent accumulated experience and serve to filter and evaluate the new day’s input. Sleep is a busy time, interweaving streams of thought with emotional values attached, as they fit or challenge the organizational structure that represents our identity. One function of all this action, I believe, is to regulate disturbing emotion in order to keep it from disrupting our sleep and subsequent waking functioning. In this book, I have offered some tests of that hypothesis by considering what happens to this process of down-regulation within the night when sleep is disordered in various ways.

Cartwright develops several themes throughout The Twenty-four Hour Mind . First is that the mind is continuously active. Second is the role of emotion in “carrying out the collaboration of the waking and sleeping mind.” This includes exploring whether the sleeping mind “contributes to resolving emotional turmoil stirred up by some real anxiety inducing circumstance.” Third is how sleeping contributes to how new learning is retained. Accumulated experiences serve to filter and evaluate the new day’s input.

The Science of Sleep: Dreaming, Depression, and How REM Sleep Regulates Negative Emotions

By maria popova.

One particularly fascinating aspect of her research deals with dreaming as a mechanism for regulating negative emotion and the relationship between REM sleep and depression:

The more severe the depression, the earlier the first REM begins. Sometimes it starts as early as 45 minutes into sleep. That means these sleepers’ first cycle of NREM sleep amounts to about half the usual length of time. This early REM displaces the initial deep sleep, which is not fully recovered later in the night. This displacement of the first deep sleep is accompanied by an absence of the usual large outflow of growth hormone. The timing of the greatest release of human growth hormone (HGH) is in the first deep sleep cycle. The depressed have very little SWS [slow-wave sleep, Stages 3 and 4 of the sleep cycle] and no big pulse of HGH; and in addition to growth, HGH is related to physical repair. If we do not get enough deep sleep, our bodies take longer to heal and grow. The absence of the large spurt of HGH during the first deep sleep continues in many depressed patients even when they are no longer depressed (in remission). The first REM sleep period not only begins too early in the night in people who are clinically depressed, it is also often abnormally long. Instead of the usual 10 minutes or so, this REM may last twice that. The eye movements too are abnormal — either too sparse or too dense. In fact, they are sometimes so frequent that they are called eye movement storms .

But what has perplexed researchers is that when these depressed patients are awakened 5 minutes into the first REM sleep episode, they’re unable to explain what they are experiencing. This complete lack of dream recall in depression has showed up in study after study, but it’s been unclear whether it’s due to patients’ reluctance to talk with researchers or to truly not forming and experiencing any dreams. That’s where recent technology has helped shed light:

Brain imaging technology has helped to shed light on this mystery. Scanning depressed patients while they sleep has shown that the emotion areas of the brain, the limbic and paralimbic systems, are activated at a higher level in REM than when these patients are awake. High activity in these areas is also common in REM sleep in nondepressed sleepers, but the depressed have even higher activity in these areas than do healthy control subjects. This might be expected — after all, while in REM these individuals also show higher activity in the executive cortex areas, those associated with rational thought and decision making. Nondepressed controls do not exhibit this activity in their REM brain imaging studies. This finding has been tentatively interpreted… as perhaps a response to the excessive activity in the areas responsible for emotions.

Cartwright spent nearly three decades investigating “how a mood disorder that affects cognition, motivation, and most of all the emotional state during waking shows itself in dreams.” What proved particularly difficult was understanding the basis for this poor dream recall during REM sleep, since anti-depressants suppress that stage of the sleep cycle, but early research suggested that this very suppression of REM might be the mechanism responsible for reinvigorating the depressed.

This brings us to the regulatory purpose of dreaming. Cartwright explains:

Despite differences in terminology, all the contemporary theories of dreaming have a common thread — they all emphasize that dreams are not about prosaic themes, not about reading, writing, and arithmetic, but about emotion, or what psychologists refer to as affect . What is carried forward from waking hours into sleep are recent experiences that have an emotional component, often those that were negative in tone but not noticed at the time or not fully resolved. One proposed purpose of dreaming, of what dreaming accomplishes (known as the mood regulatory function of dreams theory) is that dreaming modulates disturbances in emotion, regulating those that are troublesome. My research, as well as that of other investigators in this country and abroad, supports this theory. Studies show that negative mood is down-regulated overnight. How this is accomplished has had less attention. I propose that when some disturbing waking experience is reactivated in sleep and carried forward into REM, where it is matched by similarity in feeling to earlier memories, a network of older associations is stimulated and is displayed as a sequence of compound images that we experience as dreams. This melding of new and old memory fragments modifies the network of emotional self-defining memories, and thus updates the organizational picture we hold of ‘who I am and what is good for me and what is not.’ In this way, dreaming diffuses the emotional charge of the event and so prepares the sleeper to wake ready to see things in a more positive light, to make a fresh start. This does not always happen over a single night; sometimes a big reorganization of the emotional perspective of our self-concept must be made — from wife to widow or married to single, say, and this may take many nights. We must look for dream changes within the night and over time across nights to detect whether a productive change is under way. In very broad strokes, this is the definition of the mood-regulatory function of dreaming, one basic to the new model of the twenty-four hour mind I am proposing.

Towards the end of the book, Cartwright explores the role of sleep and dreaming in consolidating what we call “the self,” with another admonition against memory’s self-editing capacity :

[In] good sleepers, the mind is continuously active, reviewing experience from yesterday, sorting which new information is relevant and important to save due to its emotional saliency. Dreams are not without sense, nor are they best understood to be expressions of infantile wishes. They are the result of the interconnectedness of new experience with that already stored in memory networks. But memory is never a precise duplicate of the original; instead, it is a continuing act of creation. Dream images are the product of that creation. They are formed by pattern recognition between some current emotionally valued experience matching the condensed representation of similarly toned memories. Networks of these become our familiar style of thinking, which gives our behavior continuity and us a coherent sense of who we are. Thus, dream dimensions are elements of the schemas, and both represent accumulated experience and serve to filter and evaluate the new day’s input. Sleep is a busy time, interweaving streams of thought with emotional values attached, as they fit or challenge the organizational structure that represents our identity. One function of all this action, I believe, is to regulate disturbing emotion in order to keep it from disrupting our sleep and subsequent waking functioning.

The rest of The Twenty-four Hour Mind goes on to explore, through specific research case studies and sweeping syntheses of decades worth of research, everything from disorders like sleepwalking and insomnia to the role of sleep in knowledge retention, ideation, and problem-solving.

— Published August 13, 2012 — https://www.themarginalian.org/2012/08/13/the-twenty-four-hour-mind-rosalind-cartwright/ —

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Problem-solving in dreams (famous examples) In dreams, while our conscious mind is inactive, our subconscious mind is actively working on problems that we may have failed to solve consciously in our waking life. That's why it's highly likely that a solution to a problem that you've been working on for quite a while can pop up in your ...
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A theory to explain dreams, or any human behavior for that matter, needs to take into account evolution, Barrett said. ... Barrett has studied problem-solving in dreams for more than 10 years, and ...
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Creativity and Problem-Solving Dream Theory . Another theory about dreams says that their purpose is to help us solve problems. In this creativity theory of dreaming, the unconstrained, unconscious mind is free to wander its limitless potential while unburdened by the often stifling realities of the conscious world. In fact, research has shown ...
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An evolutionary theory of dreams and problem-solving.
Barrett, D. (2007). An evolutionary theory of dreams and problem-solving. In D. Barrett & P. McNamara (Eds.), The new science of dreaming: Vol. 3. Cultural and theoretical perspectives (pp. 133-153). Praeger Publishers/Greenwood Publishing Group. ... I posit that dreams are thinking or problem solving in a different biochemical state from ...
The Case Against the Problem-Solving Theory of Dreaming
In fact, contrary to any theory that emphasizes the problem-solving nature of dreams, dream recall is often more disturbing than it is helpful, as shown most dramatically with people who suffer from post-traumatic stress disorder. Many people also suffer from their recurrent dreams (Zadra, 1996; Zadra & Donderi, 2000a).
Dreams as Problem Solving: A Method of Study
A five-step method designed to facilitate dream understanding is sketched: it is a programmatic procedure that helps users recover aspects of their own dream formation process and probes the regulatory system by helping users discern the problem(s) a dream may be attacking.
Answers in Your Dreams
1. Write down your problem as a brief phrase or sentence and place this note next to your bed. Also keep a pen and paper—and perhaps a flashlight—alongside it. 2. Review the problem for a few ...
Activation Synthesis Model of Dreaming
The activation-synthesis theory is a neurobiological explanation of why we dream. The question of why people dream has perplexed philosophers and scientists for thousands of years, but it is only fairly recently in history that researchers have been able to take a closer look at exactly what happens in the body and brain during dreaming.
Answers in Your Dreams
The first study on dreams and objective problem solving was conducted more than a century ago. In 1892 Charles M. Child of Wesleyan University asked 186 college students whether they had ever ...
Solving Problems in Your Dreams
In fact, lucid dreaming can be very effective in getting rid of general fears and phobias. It can function as a type of cognitive behavior therapy (CBT), a type of treatment employed by many ...
DreamResearch.net: The Case for a Cognitive Theory of Dreams
Facing up to the rarity of dream recall and the lack of solutions to problems in most of the dreams that are recalled, some advocates of problem-solving theories now claim that only dramatic emotional dreams have a problem-solving function. There are two important distinctions that have to be made in considering this possibility.
PDF The Neurocognitive Theory of Dreaming: Where, When, How, What, & Why
theories. And the problem-solving theory of dream function has fewer and fewer adherents. Memory Consolidation? Social Rehearsal? Predictive Codes? Memory consolidation, social rehearsal, and predictive code theories, which now receive wide attention, assume that dreaming and dreams are adaptive without any waking recall.
Dreams as problem solving: A method of study: I. Background and theory
Considers methods of knowing dreams and what is meant by dream interpretation. Within the context of current research in cognitive science, it is proposed that at least some dreams are generated by a regulatory system seeking to establish organismic balance and, in this sense, fulfill a problem-solving function. A 5-step method designed to facilitate dream understanding is sketched: It is a ...
The Functional Role of Dreaming in Emotional Processes
In fact, dream-lag incorporation occurs more frequently in association to interpersonal problem-solving and are most evident among individuals who report that their DE affects thoughts and feelings during the waking ... Theories of dream function, in The Neuroscience of Sleep, eds Stickgold R., Walker M. (New York, NY: Elsevier Inc., Academic ...
The Cognitive Theory of Dreams
Dreams Images are the Embodiment of Thought. Central to Hall's cognitive theory is that dreams are thoughts displayed in the mind's private theater as visual concepts. Like Jung, Hall dismissed the Freudian notion that dreams are trying to cover something up. In his classic work The Meaning of Dreams (1966), Hall writes, "The images of a ...
(PDF) The Neurocognitive Theory of Dreaming: The Where ...
neurocognitive theory of dreaming. The fact that dreaming can occur dur -. ing sleep onset and for brief periods during waking in a controlled setting, demonstrates dreaming is a cognitive process ...
Dreams as Problem Solving: A Method of Study
Dreams as Problem Solving: A Method of Study — Part I: Background and Theory Show all authors. ... and in this sense fulfill a problem-solving function. A five-step method designed to facilitate dream understanding is sketched: it is a programmatic procedure that helps users recover aspects of their own dream formation process and probes the ...
The Science of Sleep: Regulating Emotions and the 24 Hour Mind
In particular, dreams are vital for helping our brains to process emotions and encode new learning. *** "Memory is never a precise duplicate of the original; instead, it is a continuing act of creation.."— Rosalind Cartwright. Rosalind Cartwright is one of the leading sleep researchers in the world. Her unofficial title is Queen of Dreams.
The Science of Sleep: Dreaming, Depression, and How REM Sleep Regulates
For the past half-century, sleep researcher Rosalind D. Cartwright has produced some of the most compelling and influential work in the field, enlisting modern science in revising and expanding the theories of Freud and those of Jung about the role of sleep and dreams in our lives. In The Twenty-four Hour Mind: The Role of Sleep and Dreaming in Our Emotional Lives (public library), Cartwright ...
PDF The Neurocognitive Theory of Dreaming
The Problem-Solving Theory of Dream Function 265 Emotions-Related Theories of the Adaptive Function of Dreaming 267 ... Dream Theories 291 Meaning, Lawfulness, and Adaptive Function 294 Looking toward the Future 296 Acknowledgments 301 References 303 Index 353. This book presents a detailed statement of the neurocognitive theory of
Dreams stimulate waking-life creativity and problem solving: Effects of
Well-known examples, e.g. Paul McCartney who composed "Yesterday" because of a dream, have shown how dreams can inspire creativity. In a sample population of 2492 participants who completed an online questionnaire the goal of this study was to examine the frequency of dreams which stimulate creative ideas and help solving problems. Participants had on average both creative ideas and ...
(PDF) Dreams and creative problem-solving
Q2. Dreams have produced art, music, novels, ﬁlms, mathematical proofs, designs for ar chitecture, telescopes, and. computers. Dreaming is essentially our brain thinking in another ...