This episode was written and produced by Olivia Rosenman.

Many of us talk to ourselves in our heads pretty much all day long. But it turns out that there are plenty of people who don’t. In fact, thinking comes in many shapes and sizes, and no two minds are exactly alike. In this episode, we explore the peculiar world of how we think, and consider the pros and cons of inner speech. Featuring psychologists Charles Fernyhough and Russell Hurlburt, and lots of 20K listeners.

MUSIC FEATURED IN THIS EPISODE

What Happens in the Park by Claude Signet
HWY 102 Holding Hollow by Makeup and Vanity Set
Excuse the Dog by Stationary Sign
Figured Out by Arthur Benson
Gem by Will Patterson
Wishy Washy by Jerry Lacey
About to Go Down by Jerry Lacey
tic tac toe by coldbrew
Domestic by DEX 1200
Spunk Lit by Love and Weasel
Satellites by Ebb & Flod
Evaporate (Cinematic Version) by SVVN
Lovely by Madron

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View Transcript ▶︎

You're listening to Twenty Thousand Hertz.

[music in]

In movies and TV shows, it’s pretty common to hear a character’s inner monologue. In this Seinfeld episode, Elaine gets stuck in a subway car, and starts panicking to herself.

Elaine: What if I’m stuck here for the rest of my life! Maybe I’ll get out in 5 seconds. One banana, two banana, three banana, four banana…

In Adaptation, Nic Cage plays a neurotic screenwriter who’s constantly second guessing himself.

Charlie Kaufman: I’m a walking cliché. The dentist called again, I’m way overdue. If I stopped putting things off, I would be happier.

And in Dexter, a lot of the dry humor comes through Dexter's inner monologue, like when he looks into an empty box of donuts.

Dexter: Just like me… Empty inside.

This trope never really seemed weird to me, because it's not too far off from the way that I think. On an average day, I spend plenty of time talking to myself, debating myself, putting ideas into words… and it all happens in my head. Honestly, it can be exhausting.

It’s so persistent, that I just assumed everyone else did this. But then, I came across this Youtube video from the CBC that completely blew my mind.

[music out]

CBC clip: I'm Olivia Rivera and I don't have an internal monologue. I always thought it was something that people just manifested and made up for movies and books and characters, just to kind of like explain your inner thought process. But I didn't realize that it was actually that constant for people, that people did actually have a little kind of voice in their head telling them what to do and what to think and stuff like that. I don't have that.

Until that moment, I had no idea that some people don’t have an inner monologue. And I’m guessing there’s a bunch of people listening right now who are just as surprised as I was. But at the same time, there are probably other people thinking, “Yeah, I don’t talk to myself in my head either…” Although that’s not exactly right… Because, those people don’t think in words.

When I started looking into this topic, I realized it was way over my head. So I got in touch with producer and journalist extraordinaire Olivia Rosenman, to help me unpack this. I’ll let Olivia take it from here.

[music in]

Olivia: What was running through your head right before you started listening to this podcast?

Charles: The problem with inner speech is that it is by definition private.

Olivia: That's Charles Fernyhough, a psychologist at Durham University in the UK.

Charles: It is something that is going on in your own head that nobody else can hear.

Olivia: What about when you first woke up this morning? Or while you brushed your teeth last night? What were you thinking then?

Charles: It's just you talking to yourself with no external signs at all.

Olivia: Were you actually talking to yourself, or was there something else going on in your head?

Charles: Inner speech is a kind of inner experience, but there's a lot more that goes on in our inner experience than just inner speech.

Olivia: Think about just how much goes on in your mind, from your most personal thoughts and feelings, to mundane lists of all the things you have to do. Songs get stuck in there. Hopes and dreams. That awkward thing you said at a work meeting three months ago that you just can’t stop thinking about.

Charles: We're commiserating with ourselves, we're being creative, we're rehearsing, we’re doing all these different things…

Olivia: There's a whole world inside your head. But can anyone else ever really understand it?

Charles: The problem we have as psychologists is how on Earth do you get at it? How on Earth do you find out about other people's inner speech?

[music out]

Olivia: So how do you study what's inside people's heads? One way is to put people in various scenarios, or have them perform different tasks, and actually scan their brains while they’re doing them. But there's another method.

Charles: Russell Hurlbert's work. His approach is a very intensive attempt to get at what's going on in a person's experience.

[music in]

Russell: If you're a subject in my research, I give you a beeper.

Olivia: That's Russell Hurlbert, a professor of psychology at the University of Nevada, Las Vegas.

Russell: The one that I use mostly looks more or less like an iPhone kind of a thing.

Olivia: The beeper has an earphone attached to it, so you can hear it at all times.

Russell: And you carry it into your natural environment, doing whatever it is that you do...

Olivia: Answering emails, [sfx: typing] making breakfast... [sfx: cooking]

Russell: Going to the grocery store, [sfx: register beeps] driving to the gas station, [sfx: car start] whatever, wearing this beeper. And at random times, it will beep. [sfx: beep]

Olivia: When you hear it, you're supposed to record exactly what was going through your head, just before the beep. You can write it down in a notebook or on your phone, you can record a voice memo...

Russell: But you get a half a dozen beeps in that way, and then we'll get together and we'll talk about that.

[music out]

Olivia: In these interviews, you have a conversation with Russell about what you noted down after each beep, and he collects all of that material as data for his research. It's a method he calls "Descriptive Experience Sampling," and he's spent years perfecting it... including the beep.

Russell: So we can't use a phone ring or something like that, because then your experience would be…

[sfx: phone ring]

Fictional Person: "Oh, my phone's ringing! Wait, that's not my phone. Oh yeah, it's that beeper thing! Oh, I'm supposed to record my thoughts!"

Olivia: But of course, that moment of hesitation would mess up your inner experience.

Russell: So we need to have a well-crafted beep, which in my world is a 700 Hertz tone.

[sfx: beep]

Olivia: It's almost like you have to ambush the thought in order to catch it.

Russell: I think that's exactly right.

[music in]

Olivia: As part of reporting this story, I volunteered to participate in Russell's research. So, he FedExed me a beeper all the way from Nevada to Australia, and I carried it with me everywhere I went. Every time it went off, I'd try to remember what I'd just been thinking about, and how I'd been thinking it. At first, I actually found it really difficult. But apparently, that's pretty common.

Olivia: So Dallas…

Yes?

Olivia: Tell me what is going on inside your head right now?

It's interesting because nothing's happening inside my head when you ask. Um, I, uh, right in my head, nothing. I think you put me on the spot and I'm like, "Oh, I can't think of a single thing." I feel like I'm ruining this.

Olivia: You're not ruining it. Relax.

Okay, good.

Olivia: I think one thing that I have found really interesting about this topic and then being involved in the research is, it's amazing how hard it is to describe what's going on in your head when you're put on the spot like that.

Russell: If you're a typical subject, you're not very good at it on the first day. So I'll say, "Well, you're pretty much typical of all subjects. Let's do it again."

Olivia: So you do it again, [sfx: beep] and you get a little bit better. And by the third or fourth time…

[sfx: beeps]

Russell: Then you'd probably be really pretty good at it. And then we could start to be sort of confident that we knew what we were talking about with each other.

[music out]

Olivia: I did this combination of beep monitoring and interview with Russel about five times. And honestly, I was surprised by what was going on in my head. Mostly it was words, there were a few pictures, and there was also a lot of music.

Olivia: Snippets of songs…

[clip: Rick Astley]

Olivia: Classical music…

[clip: Beethoven]

Olivia: And also just way too many jingles from my two year old's noise-making toys that I never buy but somehow seem to find their own way into my house.

[sfx: toy jingle]

Olivia: But one of the most interesting things I learned in the process is not to trust my intuition about how I think.

Russell: I would say that the number one take home message from my work is that you shouldn't trust your own armchair introspection about your own experience.

Olivia: So when I first read about this topic, I thought, “Oh no, I, I never think in words.”

Really?

Olivia: Yeah, yeah, that's what I thought. I thought, “Oh yeah, no, it's just, I kind of think in a… in a much more notional kind of unspecified way. I'm very rarely having a monologue or a dialogue running through my head.”

To me, that sounds amazing.

Olivia: Well, what I later discovered, however, was that I was wrong. I often, very often have words running through my head.

Olivia’s Inner Speech: "Why is it so cold in here?" “What time do I need to leave to get home by seven?” "Where did that toy even come from?"

Olivia: I will often be practicing or rehashing a conversation I've had with someone or that I want to have with someone, even though I know I'm not ever going to have that conversation with that person.

Yeah, like if I’m preparing for a conversation with someone, I can definitely kinda perceive their side of the conversation, in my head, in their voice.

Olivia: Yep, totally.

[music in]

Olivia: Part of the reason this task is so hard for people is because the word “think” has so many different meanings.

Charles: The term “thinking” is just so broad as to be almost useless, because really “thinking” is just everything the conscious mind does.

Russell: I eventually discovered that people mean very different things about their own inner life when they use the word "thought" or "thinking."

Olivia: Your definition of "thinking" really depends on your own inner experience.

Russell: And if you're a person who speaks to yourself, then what you mean by “thinking” is “speaking to yourself.” And if you're a person who sees a lot of visual imagery, then by “thinking,” you mean, "I was seeing a visual image."

Olivia: So while the word might be useful in everyday conversation...

Charles: In terms of scientific psychology, I think we can steer clear of the term "thinking" and focus on much more specific terms. And it also gets us away from the problem that philosophers have grappled with for centuries, millennia.

Olivia: That problem is, do you need language in order to think?

Charles: And I just think that's had enough air time over the centuries. And it's self-evidently wrong. You know, you can look at any small baby and you can see a person without language who is doing an awful lot of intelligent stuff.

[music out]

Olivia: In humans, thinking begins well before speaking does. But even after we learn to talk, some of us don't rely on language in order to think. Thankfully, Russell has come up with a classification system for the things that happen inside people's heads. There are five different categories.

[music in]

AI Voice: Category One: Inner speaking.

Russell: …where people talk to themselves, and that experience for most people is pretty much like speaking aloud.

We asked our listeners to call in and describe their own inner experience. And like me, many of you talk to yourselves in your head.

Kim: I definitely think in words, but it's almost like it's slowed down into a sitcom voiceover. "Hmm. So listeners, what did she do next? What should she do next? What does she really think about that? Hmm."

Kristopher: I have an internal monologue that maybe 95% of the time is a more calm and collected version of myself.

Meg: This is how I think. Full on conversations, full on TED Talks inside my brain.

It feels like there's a internal debate going on between multiple versions of me. And sometimes it's very hard to say, "Hey everyone up there, stop and shut up for a second."

[music out]

AI Voice: Category Two: Visual imagery.

Russell: So they have the experience of seeing when there’s nothing in the real world that looks like what they’re seeing.

[music in]

Trevor: When I think about my day, I see the actual pictures. I see the events. I see what could happen, what might happen, worst case scenarios, best case scenarios.

Paul: So rather than thinking the sentence, "I'm going to the city to shop today," it would rather just be a fleeting image of my getting in the car and arriving at what I recognize to be the city.

Guil: For me, they're played out as a movie or play. It's one of the reasons why I think I don't dream at night, because I'm constantly wasting my dream juice during the day with this daydream 2.0.

[music out]

AI Voice: Category Three: Emotions.

Russell: People have feelings, and some people have feelings a lot and other people don't.

[music in]

Sisi: If it's my feelings or emotions or things like that, I kind of just feel them. I don't really have a word to them.

AI Voice: Category Four: Sensory Awareness.

Russell: So you might be seeing the computer screen but paying particular attention to the color of the font. Or if I'm attending to a scratchiness in my throat, I would call that a bodily sensory awareness as well.

AI Voice: Category Five… Well, this one is a bit harder to define.

[music out]

Russell: The fifth one is what I call unsymbolized thinking.

[music in]

Russell: And people who engage in unsymbolized thinking will be able to tell you, "I was thinking about something and this is exactly what I was thinking about." It's not a vague thing. But that thought is not conveyed in words, or visual images, or any other kind of symbols.

Charlotte: If I'm like, for instance, planning out my day, it's not so much like a list of words or things. It's kind of more like a flow chart of like places and concepts.

Rahul: What I find is that my thoughts are formed in simply the language of thought. There's no diction or syntax in this language. It's just a jumble of synapses firing. It's a tangled mess of cables and unmatched socks. They present themselves as disordered masses without visible structures of coherence, or networks of logic or data to tie it all together.

[music out]

Olivia: According to Russel, all five categories are pretty much equally common. And each one is a sliding scale. So you might do a little of one category, and a lot of another. Some people might even do them all at the same time.

[music in]

Rawan: My thoughts encompasses all the senses. It's not just words, it's an image I see, it is something I taste, it is something I feel, it is something I smell, and it just, it's all encompassing. It's as if I'm actually living that thought at that moment.

Olivia: But for people who do think in words, why exactly do we do it? When did humans start doing it? And what about people who experience voices that don't seem to be their own?

That's all coming up, after the break.

[music out]

MIDROLL

[music in]

Up until recently, I was under the impression that everyone thought in words. But when we asked our listeners, I was surprised by how many of you apparently don't.

Charlotte: If I'm worrying about something, I of course think of it, like I can visualize how things could go wrong, but I'm not doing like a voiceover narration, like "Top 10 Projected Cringe Moments."

Linda: I would find that so annoying to constantly have someone speaking, even if it's my own voice, especially if it's my own voice. So I'm very grateful for the silence between my ears.

[music out]

Olivia: Of course, Russell Hurlburt would say that we should take all of those messages with a grain of salt. And that’s because, as my experience showed, people's instincts about how they normally think can often be wrong.

Olivia: Still, it's clear that talking to yourself in your head is not universal, even if it is extremely common.

Charles: Lots of people do it actually. They probably do it because at least some of the time it's helpful, it's useful. And the question I want to ask is how is it useful? What kind of language goes on in people's heads?

[music in]

Olivia: For Charles, the most useful term for this phenomenon is inner speech.

Charles: I have concerns with some of the other terms that float around. So you often hear the term "internal monologue." That's fine, except I don't think inner speech is a monologue for a lot of the time. In fact, I think a lot of the time it's a dialogue.

It's like different voices of different emotions and, you know, point counterpoint, the angel on one shoulder, the devil on the other shoulder. It's all me, and I hear it or perceive it in my own voice, but it's almost just like I'm talking to myself and working problems out.

Olivia: Another term people use is "inner voice."

Charles: My problem with that term is it just gets overgeneralized to incorporate all sorts of experiences that people have. They say, "My inner voice told me to make some moral choice," or they say, "My inner voice is guiding my creativity." And that's all fine. But is it actually about language? Is it actually about words? Is it actually about speech?

[music out]

Olivia: One thing that Charles hopes to learn is when and why this inner speech begins in people.

Charles: The theory that I've followed and tried to develop is the theory of the Russian psychologist Lev Vigotsky, who argued that children start off in the social world. They're interacting with others from day one. And when language kicks in around about 12 months, roughly, it gives the child so many different ways, so many powerful ways to interact with other people.

[music in]

Olivia: Suddenly, they can tell people when they want something.

Toddler: I want a cookie!

Olivia: What they like and don't like...

Toddler: I like dogs!

Toddler: Spinach is gross!

Olivia: And what they want to do next.

Toddler: Let's play Legos!

Charles: So language starts off as a social thing. And in time, those words, which were directed to others get turned back onto the self. So first through this out loud stage of private speech.

Olivia: When he says the "out loud stage of private speech,” he's referring to that thing you often see toddlers do where it’s kind of like they're narrating their life.

Toddler: "I'm building a sand castle!"

Toddler: "I'm taking my puppy dog over here."

Charles: And then eventually the whole thing goes upstairs. The whole thing becomes internalized, and becomes the inner speech you and I would recognize.

[music out]

Olivia: But why do we take it upstairs?

[music in]

Charles: There are all sorts of interesting evolutionary, psychological stories you could tell about this.

Olivia: The first one starts hundreds of thousands of years ago, when humans were nomadic, hunter-gatherers. First, we started speaking to each other, which was really useful for collaborating, problem solving, forming relationships…

Charles: And then we thought, "Hey, it's pretty cool I can talk to myself and I can make stuff happen. I can make things easier for myself as I'm working through problems."

Olivia: But we quickly figured out that there are some good reasons for keeping our self-talk on mute.

Charles: One would be that you don't want to give your location away. [sfx: savanna, tiger steps] You know, when we're trying to keep away from the saber tooth tigers, [sfx: tiger growl] you don't want to be mumbling to yourself out loud as you cower behind a bush. [sfx: mumble + tiger snarl]

Olivia: Another reason has to do with competition among your own species.

Charles: If you think all your best ideas out loud, somebody else is going to nick them. You're gonna give you plans away. You're gonna, you know, lay your cards on the table.

[music out]

Olivia: In modern society, the pressure to keep our thoughts inside often begins at school.

[sfx: classroom sounds]

Charles: And any elementary classroom teacher will say to you, "If you have 30 kids talking out loud to themselves the whole time, it would be quite hard to make anything happen." So culturally, one of the things that has happened to us is that we go to school, and we keep those words in to ourselves, we put a lid on it.

[sfx: “Hush!”]

Olivia: So whether you're a cave dweller or a preschooler, there are plenty of reasons not to talk to yourself out loud all day. But as you get older, that can change, too.

Charles: My son caught me coming out of a room the other day and sort of gave me a funny look and said, "Were you just talking to yourself?" And I said, "Yes, I do that all the time." I'm pretty sure I didn't do that when I was his age. So it's about the social inhibitions. It's like, why you’re happy to dance to ABBA at a wedding. You know, you don't care so much as you get older.

[clip: wedding scene with ABBA’s Dancing Queen]

Olivia: But while inner speech can help us plan and create and problem solve...

Charles: It definitely has a negative side.

[music in]

Olivia: For many people, inner speech can be a source of great discomfort.

Charles: So worries and anxieties, and particularly rumination, thinking in words over and over again about something that's happened can be a really troublesome thing for a lot of people.

Olivia: Persistent, negative self-talk is often associated with conditions like anxiety and depression. But we're still learning about how these things interact. For instance...

Russell: Most people do not experience themselves as saying something in their head before they say it out loud. There are some people who do that. And I associate that with anxiety. Some people who have anxiety do experience themselves as innerly speaking before they outerly speak.

Olivia: But so far, it's not clear whether this tendency is a cause of anxiety, or a result of it.

Olivia: Another potential problem comes when you start experiencing speech that doesn't seem to be your own.

Charles: Voice hearing. It comes in many, many different shapes and sizes. It can be very distressing.

Olivia: One hypothesis is that these voices are essentially just a type of inner speech that somehow gets misidentified.

Charles: Maybe what's happening when someone's hearing a voice is that they're actually just doing some inner speech. But for some reason, they don't recognize that speech, that language that results, as being something they themselves produced. And so it's felt, it's experienced, as an external, as an alien voice.

[music out]

Olivia: To help treat people who are distressed by the voices they hear, Charles and a team of researchers have been developing an unusual technique.

Charles: So one of the things that we do in our therapy is we ask people to kind of play around with their inner speech, to do some inner speech, but do it, you know, making the sound of Donald Duck…

Donald Duck: Well uh, I don’t know.

Charles: Or some other kind of strange, funny accent.

Wario: I’m number one!

Charles: Whatever they want, whatever they feel comfortable with. And for some people that helps them to understand that this thing that's going on in their head is actually just them speaking. And it's something that they can have some control over. It doesn't work for everyone. It seems to work particularly for people who are just starting to have these experiences for the first time.

[music in]

Olivia: We still have so much to learn about how our brains work. But the answers are out there. And as Russel's research has shown, you can get a long way just by talking to people.

Russell: People want to tell you about what's going on in their experience as it actually is. I think they know the difference between what their actual experience is, and what they have practiced telling their friends, or the mask that they put on.

Charles: Inner speech is so intimate. It's so familiar that we hardly know we're doing it. And when you ask people about it, you often get this sense of surprise of, " Oh, I've never really thought about that, but it actually, of course, I should have thought about that because I probably do quite a lot of it."

The brain is our most complex organ. It's the control center for all of our movements, our senses, our thoughts, our feelings… And the way we experience the world, on a day to day basis, ties into all of these things. So understanding this better will open up all kinds of possibilities...in mental health, in early childhood education, in medicine, and beyond.

Charles: Inner speech probably connects with all sorts of other things that we do, with our emotions, with our creativity, with memory. It's a kind of currency or a common language for much of what our minds do, I think. And that to me is about as interesting as it gets.

Twenty Thousand Hertz is produced out of the sound design studios of Defacto Sound.

Olivia: This episode was written, produced and reported by Olivia Rosenman.

It was story edited by Casey Emmerling, with help from Grace East. It was sound designed and mixed by Justin Hollis.

Thanks to our guests, Charles Fernyhough and Russell Hurlburt. To learn more about this topic, check out Charles' book The Voices Within, and also check out Russell's book, Investigating Pristine Inner Experience. There are links to both in the show notes.

Thanks to all of the listeners who sent in messages about this, including Charlotte, Guil, Kim, Kristopher, Linda, Meg, Paul, Rahul, Rawan, Sisi, and Trevor.

Here at Twenty Thousand Hertz, this topic sparked a lot of interesting conversations. So if you know someone who would like this episode, I’d really appreciate it if you would share it with them.

I'm Dallas Taylor. Thanks for listening.

[music out]