Inner monologues are still a mystery

Emily Kwong https://www.npr.org/people/767284140/emily-kwong is pretty sure she lacks an inner monologue, while the inner monologue of producer Rachel Carlson https://www.npr.org/people/1112796909/rachel-carlson won’t stop chatting. But how well can a person know their inner self? And what does science have to say about it? We dig in in this encore episode of Short Wave. To learn more about Charles Fernyhough’s research on voice hearing, visit the project website https://hearingthevoice.org/about-the-project/. If you liked this episode, check out our episode on when your brain is actually an "adult." http://lnk.to/Frh1Lg Interested in more science inside your brain? Email us your question at [email protected] mailto:[email protected]. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave http://plus.npr.org/shortwave. See pcm.adswizz.com https://pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences. NPR Privacy Policy https://www.npr.org/about-npr/179878450/privacy-policy

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Speaker 00

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• 0:12Speaker 01

  You're listening to Short Wave from NPR.

• 0:17Emily Kwong?

  Hey, Short Wavers. It's Emily Kwong.

• 0:19Speaker 01

  And Rachel Carlson, Short Wave producer. And Emily, I think it's pretty safe to say that both of us read the team inbox, [email protected].

• 0:28Emily Kwong?

  Every morning fervently.

• 0:29Speaker 01

  Exactly. And two months ago, you said something to reporter John Hamilton that really piqued our audience's interest.

• 0:38Emily Kwong?

  I don't have an inner monologue.

• 0:39Speaker 03

  Not everybody has an inner monologue. This is something that doesn't work for everybody.

• 0:45Emily Kwong?

  I'm safe.

• 0:45Speaker 03

  Yeah, exactly.

• 0:48Emily Kwong?

  I'm so proud of myself.

• 0:49Speaker 01

  And our inbox lit up about this. People wrote, is that even a thing? I don't understand. How is that possible? So we had to confirm. Science backs this up, right? Not everyone has an inner monologue.

• 1:03Emily Kwong?

  It is true. Scientists confirm. For some people, inner speech is far less wordy. So my inner experience isn't really word-based. It's more like a moving landscape of images. It's kind of like soaking in an emotional bath and like feelings.

• 1:20Speaker 01

  I love it.

• 1:21Emily Kwong?

  Yeah, and feelings and images will rise and they'll fall. But there's no words. It's real silent.

• 1:28Speaker 01

  Mine is loud. Oh, no. It does not feel like a bath. It feels like it's dialogue-heavy. So whether it's a conversation that I'm having with myself or an imagined conversation with other people. Yeah, it's a screenplay.

• 1:45Emily Kwong?

  Me, myself, and my voice.

• 1:46Speaker 01

  Yeah, totally.

• 1:47Emily Kwong?

  La, la, la, la.

• 1:48Speaker 01

  But Emily, this got us thinking about how different the insides of people's heads are. And it turns out there are scientists who study what's going on in people's minds.

• 1:57Speaker 04

  I think it's the most interesting question on the planet. The earliest known writings like Gilgamesh or whatever you call their earliest writings are interested in inner experience.

• 2:07Speaker 01

  This is Russell Hurlbert, a psychologist at the University of Nevada. And Russ is a legend in the field for being one of the first to gather data on inner experiences through a beeper. Participants carried this device around, and every time it beeped, They filled out a questionnaire to quantify their inner experience. But there was a problem.

• 2:29Speaker 04

  People didn't know what they were talking about when they picked a number on a Likert scale. And I didn't know what they were talking about. The data was just rotten on the way in.

• 2:37Emily Kwong?

  So he ditched the questionnaires and instead told participants, every time the beeper goes off, write down what's going on internally, in your own words.

• 2:46Speaker 04

  And then we get together and talk about it.

• 2:48Emily Kwong?

  Russ called this technique descriptive experience sampling. It was illuminating, sometimes even life-changing for the participants involved. But Russ is the first to say how highly imperfect his method is.

• 3:00Speaker 01

  It's just people saying what's going on in their heads. But how do you confirm?

• 3:04Emily Kwong?

  Yeah, like, how do you check for accuracy? Like, he believes that people do not fully know the characteristics of their inner experience, including me.

• 3:12Speaker 04

  You've got no good reason to be confident that you do or do not have an inner monologue. Because there's just too many layers between what your inner experience actually is and what you might say about it.

• 3:29Emily Kwong?

  That was humbling to hear.

• 3:30Speaker 01

  It's humbling, yes, but Emily, you know, even if people can't fully know themselves, scientists are still trying to figure it out, including a collaborator of Russell's, Charles Fernyhough.

• 3:43Speaker 05

  We've shown that you can do it. Not just us, teams all around the world have shown that you can study this stuff. You can have a science of it.

• 3:50Emily Kwong?

  So today on the show, how far can the science go in the quest to know thyself? I'm Emily Kwong.

• 3:57Speaker 01

  And I'm Rachel Carlson. You're listening to Short Wave, the science podcast from NPR.

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• 5:39Emily Kwong?

  Okay, short waivers. Rachel and I are here with Charles Fernyhough. He's a professor of psychology at Durham University and studies inner speech, which is one of many kinds of internal experiences. Charles, what do we know about where inner speech comes from and what parts of the brain are involved?

• 5:55Speaker 05

  Well, if you watch any small child, you're really likely to see them talking to themselves.

• 6:01Emily Kwong?

  Yes.

• 6:02Speaker 05

  So when kids are talking to themselves out loud, we call that private speech. And the idea is that it's the precursor. It's the thing that comes before inner speech. So the inner speech that you and I probably experience or may not, where that comes from developmentally is from private speech. And in turn, that private speech came from the social dialogues that those, that kid enjoyed when they were growing up. So, you know, talking to caregivers, other adults, other, other children.

• 6:33Speaker 05

  And gradually, internalizing those conversations, they become conversations with the self.

• 6:39Speaker 01

  Wow.

• 6:40Emily Kwong?

  You're saying basically like, because we're born into this social world with all these people around, like my niece's little monologue, when she's like talking to herself, will eventually become internalized and that is her inner speech.

• 6:54Speaker 05

  Yeah, exactly. That is the, is the theory of a great Russian psychologist called Lev Vygotsky, who was writing this stuff about a hundred years ago. His work has become increasingly influential in recent years. And it's a really simple, neat little theory that nobody's got to the bottom of yet because it is so rich. It has such implications for the way our minds work.

• 7:16Emily Kwong?

  Hmm. Where is that in the brain? Or where can we see it in the brain?

• 7:21Speaker 05

  Well, as you'd expect, you see the language systems that we know about, mostly lateralized onto the left hemisphere.

• 7:31Speaker 05

  A bit of towards the front called Broca's area, which is often involved in producing, you know, complex action patterns. A bit further back called Wernicke's area, which is responsible for processing speech, including speech from other people. That, those two areas create a kind of resonating loop, which we, which always shows up when we ask people to speak to themselves or out loud in the scanner.

• 7:57Emily Kwong?

  What kind of scanner? Like a CT scanner, an MRI scanner?

• 7:59Speaker 05

  These days, it's going to be an MRI scanner, yeah, when we're doing FMRI

• 8:03Emily Kwong?

  Okay.

• 8:04Speaker 05

  research on, on the topic. So we see those systems lighting up. But, I mean, that bit of the front Broca's area lights up when we do a whole load of different things. So we can't really pin too much onto that. So we know it's important, but it's not the whole story.

• 8:18Emily Kwong?

  How so?

• 8:19Speaker 05

  So one of the things that we've argued, you know, if inner speech comes from a dialogue with other people, it should have the structure of a dialogue. In order to do that, your language system has got to be working. All that stuff on the left hemisphere that you'd expect to be working, but some other stuff must be going on as well.

• 8:37Emily Kwong?

  Oh, interesting. Okay. So you're saying that would involve more parts of the brain than just the language areas?

• 8:43Speaker 05

  Yeah. And what we find when we look at people doing dialogic inner speech, as opposed to something that's more like a single line of conversation, is that yes, you get that language system in the left hemisphere firing. But you also get another region way on the other side of the brain, which we know from previous research is involved in representing other people's minds. So you're representing yourself as a partner in that conversation.

• 9:08Speaker 01

  Wow.

• 9:09Emily Kwong?

  Wow. We heard from Russell Hurlbert how there's like limits to surveying. Like you can't really know what's going on in someone's inner experience fully, nor can they. How has the the addition of scanning deepened our understanding of inner speech? Or complicated it to the point where maybe we there's even more that we don't know?

• 9:32Speaker 05

  The cool thing about working with Russ was that we had a study where we we got people used to using descriptive experience.

• 9:40Emily Kwong?

  The beeper. Yeah.

• 9:41Speaker 05

  Yeah, the beeper. Yeah, they got used to using the beeper. Once they got pretty good at it, we then put them into the scanner.

• 9:47Emily Kwong?

  Hmm.

• 9:47Speaker 05

  And we we saw what they were doing. So we had two kinds of inner speech. We sort of caught two kinds of fish.

• 9:54Emily Kwong?

  Oh, gosh.

• 9:54Speaker 05

  One is the elicited inner speech where you're told to do it. And the other is the spontaneous inner speech where you're not told to do it. It just happens. And we could look to see whether these two kinds of things were the same. And we've got a whole lot further to do on this topic. But what we found is they didn't look the same in terms of that

• 10:15Emily Kwong?

  Wow.

• 10:16Speaker 05

  balance of activation between Broca's area and Wernicke's area. So when we had elicited inner speech, there was lots of that Broca's area, the bit at the front on the left that's producing, producing, you know, doing these high, complex movement patterns, including speech. But when people were doing inner speech spontaneously, there was much less of that.

• 10:37Emily Kwong?

  Just like chilling in the machine and they just had an errant thought that was inner speech.

• 10:42Speaker 05

  Exactly. And it was more of that that region bit further back.

• 10:45Emily Kwong?

  Wow.

• 10:46Speaker 05

  The Wernicke's area.

• 10:46Emily Kwong?

  Wow.

• 10:47Speaker 05

  That was more the kind of listening, heary bit of the the brain.

• 10:50Emily Kwong?

  Fascinating. Yeah.

• 10:51Speaker 05

  You know, that the exact areas of the brain doesn't matter too much. But for us, it was a really important sign that more needed to be done here. And that we shouldn't assume that when you put somebody in the scanner and tell them to do something, the thing that results is anything like the thing you're actually interested in. So neuroscientists beware. You know, are people really doing the kind of thing in the scanner that you you want them to be doing?

• 11:14Emily Kwong?

  Yeah.

• 11:15Speaker 01

  Yeah.

• 11:15Emily Kwong?

  I mean, that kind of inner speech, like spontaneous inner speech sounds. Like birding, you scientists have to patiently wait and see if a bird shows up?

• 11:24Speaker 01

  But the bird is your own brain.

• 11:26Speaker 05

  I love it. Yeah, exactly.

• 11:28Speaker 01

  I mean, okay, so you also lead this project on voice hearing. So can you just tell us what voice hearing is and how it differs from spontaneous inner speech?

• 11:40Speaker 05

  So we use the term voice hearing to describe the experience of hearing a voice when there's nobody around to have produced that voice. And we usually associate it with severe mental illness, so diagnoses like schizophrenia. What we've learned is that this experience happens to all sorts of people in all sorts of walks of life. Many, if not most psychiatric disorders have voice hearing associated with them. But then there are, you know, a significant number of people who hear voices, who are not distressed by them, who don't seek psychiatric help, who don't need psychiatric help because they're not distressed, but find them useful, creative, guiding, spiritual, all these kinds of things.

• 12:25Speaker 05

  So the question of how that relates to inner speech, the theory is that when somebody hears a voice, what's actually happening is that they're producing some inner speech. So they're talking to themselves. But for some reason, that is not experienced as their own voice. It's experienced as coming from some sort of other entity or some sort of other place. And there's a good neuroscientific theory of why that works. And it goes back to those two parts of the brain, in fact, that bit broker at the front, that bit vernicker at the bit further back. The idea is that when, usually when you're speaking, that bit at the front sends a little

• 13:07Speaker 05

  internal message to that bit in the middle and says, you're about to speak. Don't pay too much attention to it. Don't kind of process this like you'd process somebody else speaking because it's just you. And the idea is that in the case of voice hearing, that message doesn't get through in the same way. It's delayed, or it's degraded, or it doesn't happen at all.

• 13:24Speaker 01

  Wow.

• 13:25Emily Kwong?

  So your brain can't tell it's you who's talking?

• 13:27Speaker 05

  Yeah, pretty much, yeah.

• 13:28Speaker 01

  Hmm. What's the difference between that and not having inner speech?

• 13:34Speaker 05

  The work that Russ has done and the work that I've done with him has made it really obvious to me that some people don't use inner speech very much. Maybe some never use it at all. They do other things.

• 13:47Speaker 01

  Yeah.

• 13:48Emily Kwong?

  Yeah.

• 13:48Speaker 05

  They use images. They use music. They use emotions. They use all the other stuff that's going on in your head.

• 13:56Speaker 01

  Hmm.

• 13:57Speaker 05

  It's also made it obvious to me that we're really bad at judging what's going on in our heads.

• 14:01Emily Kwong?

  But if if speech is just a tool, do you think that an adult can develop their inner speech? Like, is it is it better to have one?

• 14:11Speaker 05

  I'd like to celebrate the diversity of human minds. I think we are so different.

• 14:16Speaker 01

  I think that's beautiful.

• 14:18Speaker 05

  I think it's wonderful that there is this diversity and we and we can celebrate that diversity. I wouldn't ever want to set out and say to people that they should improve their inner speech. But what I would say is that sometimes inner speech can have a negative side. And if your inner speech is bothering you, if it's excessively critical.

• 14:38Speaker 01

  Ah.

• 14:39Speaker 05

  You know, it can be wrapped up in all kinds of stuff that isn't particularly good for your mental health. And I'd say if if that's bothering you, there are maybe things that you can do to to rethink it. And if people have any concerns or want to know more about hearing voices, we have a website called understandingvoices.com where you'll find a whole bunch of different kinds of information about voice hearing, including how people make sense of voice hearing, what people do to seek help for voice hearing and so on.

• 15:10Emily Kwong?

  Charles Fernio, thank you so much for coming on Short Wave to talk about this. I think Rachel and I are a little speechless.

• 15:17Speaker 01

  I'm speechless, yeah.

• 15:19Speaker 05

  Thank you, Baze.

• 15:22Emily Kwong?

  This episode was produced by none other than Rachel Carlson. She really does it all.

• 15:26Speaker 01

  Thank you. It was edited by our showrunner, Rebecca Ramirez, and fact-checked by Tyler Jones.

• 15:32Emily Kwong?

  Kwasi Lee was the audio engineer. And Beth Donovan is our vice president of podcasting. I'm Emily Kwong.

• 15:38Speaker 01

  And I'm Rachel Carlson.

• 15:39Emily Kwong?

  Thanks for listening to Short Wave from NPR.

• 15:55Emily Kwong?

  Stay tuned for the following announcements and messages from our sponsors.

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• 16:22Speaker 00

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