[ ♪ intro ] Maybe it shouldn’t be surprising that writers
give so many superheroes, alien beings, and magical creatures the power of telepathy. Just imagine what you could learn about a
person if you could hear their thoughts. Well, actually, I’ve just made a bit of
an assumption there: that there’d be something to hear. Because not everyone has that kind of internal
monologue—or, what psychologists often refer to as inner speech. And even people who do hear their thoughts
don’t necessarily talk in their heads 247. It turns out that inner speech could tell
us a lot about how our brains work, how they develop, and how we speak. But… research on all this is really just
getting started. Inner speech is somewhat loosely defined as
when a person “speaks” meaningful thoughts without producing sound or moving any part
of their body, like their tongue or their lips. Though, in some ways, it’s easier to define
by what it isn’t. It’s different from visualizing or picturing
things in your head. And it doesn’t include feelings like happiness
or hunger, or your awareness of sensory experiences, like noticing the glint of something shiny
on the ground. So basically, it only refers to thoughts accompanied
by specific words. These words usually have the same tone, inflection,
and even accent that they would if were spoken aloud—though not always, which we’ll get
to in a bit. Even figuring that much out about inner speech
was somewhat of a challenge for psychologists, because—surprise!—it’s really hard to
measure people’s internal experiences. So there’s been a lot of variation in research
methods, and not a lot of agreement between different studies and different scientists. For example, some studies have tried to see
inside people’s heads by prompting them to hear specific words or phrases in their
mind—like, by asking them to read something silently or determine if two words rhyme without
saying them out loud. That’s revealed some weird quirks about
inner speech—like that, when people read, they’re actually much more likely to mentally
say single words that represent a passage than every word of every sentence. But prompted inner speech and spontaneous
inner speech aren’t really the same. Plus, prompts can't tell us much about how
frequently or why people use inner speech in their daily life. So, some researchers use questionnaires instead. According to those, these conversations we
have with ourselves are generally about... ourselves. And kind of in a bad way. Most of the time, our inner speech consists
of negative things about ourselves, our negative emotions, or us trying to decide if we’re
good enough. And, weirdly enough, that’s all usually
in full sentences. Only about one-third of people experience
abbreviated inner speech, where a single word or phrase represents an entire complex thought. So… the opposite of what happens when we
read. Questionnaires have also tried to get at the
question of how often people engage in inner speech, but they have a few limitations. Perhaps the most glaring is that people generally
aren’t great at being aware of their inner experiences, so questionnaires probably overestimate
the frequency of inner speech. More recently, researchers have started using
a procedure called Descriptive Experience Sampling, or DES instead. With DES, people carry a beeper that goes
off randomly throughout the day. And when it does, they write down some notes
about exactly what was going on in their head at that moment. It’s like when you’re sitting across from
your friend and you’re like “what ya thinking about?” It’s not perfect. Some researchers think that DES goes too far
and underestimates inner speech, for example. But it is giving scientists a better sense
of how many people “hear” their thoughts and how often. And it’s revealed that inner monologues—like
most things in psychology—are on a spectrum. Very few people have no inner speech at all,
and very few people engage in it one hundred percent of the time. DES studies suggest that seventy to eighty-five
percent of people experience some kind of spontaneous inner speech at least occasionally. And of those people, most of them are talking
to themselves about fifteen to thirty percent of the time. It’s also possible to have more than one
internal experience simultaneously, so you might be visualizing something and talking
to yourself about it. And inner speech varies in other ways, too. While a lot of people talk about this in terms
of internal monologues, about seventy-five percent of people report that sometimes they’re
having back-and-forths in their head. They usually play both parts in the conversation,
though—only about twenty-five percent of people report that other people show up in
their inner speech. People who have ever had an imaginary friend
are more likely to use this kind of dialogic speech, even if they don’t have that friend
anymore. Which is pretty cute. Others might experience something a little
different but similar: what psychologists call imagined interactions. Basically, that’s when you imagine all the
things you should have said to that guy who stole your parking spot, or rehearse what
you’re going to say to your date later. What’s not clear in all of this is why people
have different inner monologues or dialogues, and what those differences say about them. We don’t even really know where inner speech
comes from. From an evolutionary standpoint, many experts
think that inner speech came about as part of the process for generating overt speech. It may even be a side effect of sorts of spoken
language that’s been co-opted for other cognitive tasks. See, when you go to speak, your brain simultaneously
sends signals to two different areas: one to motor parts of the brain to control the
mouth and the tongue and stuff, and a copy to the sensory parts of the brain. The sensory signal allows the brain to make
a prediction about what it’s about to hear. Essentially, you recite words in your head
as you say them out loud. And it turns out that same kind of signal
occurs during inner speech. That may be why you can quote “hear” yourself—you’re
literally activating the hearing part of your brain. And some psychologists think this means the
underlying purpose of internal speech is to catch errors when you talk. If the internal prediction matches what you
say, your brain knows it can filter your words out of what it’s hearing and focus on the
rest of the sounds coming in. If they don’t match—like if you stumble
over a word—your brain lets you know that you made a mistake so that you can stop and
correct yourself. But it doesn’t seem like this error correction
is absolutely essential for speech, because the two can be separated from one another. There are cases of people with brain damage
who lose their inner speech but not the ability to talk, and vice versa. Still, inner speech could have helped people
communicate better, which could explain why it evolved. This is just the prevailing hypothesis, though,
and it’s possible it’s wrong. Also, it’s likely that even if inner speech
started this way, the brain has repurposed it for other uses. Those other uses might explain why it differs
between people. Some psychologists think our everyday inner
speech reflects conversations that we had out loud as kids—especially moments when
our caregivers talked us through solving a problem or calmed us down. The idea is that these teaching moments get
internalized as we grow up, and then we essentially replay them in our heads later—which would
explain why inner speech often resembles a conversation. And, this could explain why, content-wise,
it’s often about self-regulation—things like problem-solving, planning things out,
time management, and motivation. Those are all things someone would help talk
their young child through. Plus, the same brain areas are activated during
internal dialogic speech and when a person is thinking about someone else’s experience
and perspective. That would make sense if the voice in your
head is basically your brain recycling someone else’s words. So, if this theory is correct, inner speech
might be different between people simply because their upbringings and social interactions
were different. We still don’t know how or if those differences
matter, mind you. But there are some big clues that inner speech
plays an important role in cognition—so, all those brain processes involved in thinking. For instance, scientists have used a test
called a dual-task paradigm to see how inner speech affects problem solving. Basically, they ask the person to solve a
problem while doing something else. And if that second task is physical—like,
tapping their foot—they generally have no problem with it. But if it’s verbal—like, remembering a
list of words—then they perform worse. Researchers think that’s because those words
disrupt their inner speech, making it so they can’t really talk themselves through the
problem. Inner speech may also be an important tool
for memory, and more specifically, working memory. That’s the memory where you store the information
you want to access really quickly. One of the components in working memory is
the ability to repeat information to yourself until you no longer need it—and for that,
you need inner speech. In fact, people who do more self-managing
inner speech—so, things like talking themselves through solving a problem—do seem to do
better on some cognitive tasks. So differences in how people talk to themselves
might underlie differences in how well they perform different kinds of thinking. Inner speech may also play a part in mental
health conditions. Research has connected it to depression and
anxiety, for example. People who have more depressive tendencies
tend to experience more depressive self-talk. And we know that people who are more anxious
tend to engage in more self-critical inner speech. It’s not clear if these negative forms of
inner speech exacerbate or even cause those conditions, or if the conditions lead to higher
amounts of negative inner speech. Though, studies have found that if you ask
people to think verbally about hypothetical situations—even positive ones—their mood
is lower than if you ask them to picture the hypothetical situations instead. And that does support the idea that the speech
part of inner speech might make people less happy… for some reason. Other research has tied inner speech to symptoms
common in psychotic disorders. For example, people with schizophrenia often
report hearing voices of people speaking to them or telling them what to do. One theory is that those “voices” are
actually inner speech. Remember that prediction signal I mentioned
earlier? Well, some experts think that if something
in that neural circuit is off, then the brain’s usual way of identifying self-made sounds
and thoughts could be off, too. So basically, that person’s brain might
not be so great at separating sounds they generate from ones they hear. And that may mean it also attributes inner
speech to someone else. Because of these potentially important roles
in cognition and mental health, psychologists are eager to gain a better understanding of
what inner speech is and why it happens. And figuring all that out could tell us a
lot about, well, a lot—from how our brains develop and work to what’s actually happening
in a variety of mental disorders. But as of right now, we just don’t know
that much about this thing most of us do every day. There are a lot of big questions currently
unanswered, like where inner speech comes from, why it differs between people, and what
those differences mean. Like, can you change your inner monologue? Can you train yourself to think in conversations,
or to hear other voices or your own more often? We don’t even know if you should want to
make those changes—if there are the benefits or downsides of different kinds of inner speech. And it’s probably going to be a while before
we have any clear answers, because our methods for studying it just aren’t great, and there’s
a lot of debate over basic questions, like how many people even do it in the first place. In the meantime, though, you can still talk
about it amongst yourself. Thanks to Eric for asking us about this topic,
and to all our other patrons who support us on Patreon. We love hearing what you want to learn about! If you’re one of our awesome patrons, be
sure to hit up that QQ inbox from time to time, or jump onto the Discord to nerd out
about sciencey things with other patrons and some of our staff. And if you’re not a patron already, you
can learn more about joining our awesome, science-loving community at Patreon.com/SciShow [ ♪outro ]
My wife and I have discussed this. Yes, I have internal dialogue, but it's not the majority of my thoughts. Hers is.
Like, she says that her inner dialogue is the same as it is portrayed in the show Dexter, or Scrubs. Which is insane to me. I think mostly in images and concepts as the poster before said. And they're not even good images, because my visualization abilities are crap.
Anyway, because of this, it is more difficult for me to articulate because I have to translate all these abstractions into usable language, which can take time. A LOT of time. Time that I don't seem to have as much of as I get older.
But, to the point of the post - the negativity that seems to be inherent of an inner dialogue. I would have to agree. It's the voice that tells me, to put very simply, not to fuck up. It's either very critical of myself, and it's very aggressive to others.
The only positive inner dialogue comes from looking at my wife in moments of love and attraction, actually. Huh. Well, at least there is that.
Thanks for sharing the post and, if you cared to do so, reading my stream of consciousness.
“Beans” - dangerous forces are afoot!
Thanks for sharing. Hank is pretty entertaining and it’s very interesting how broad of a spectrum inner dialogue is. Mine is rarely an “inner voice” unless I am being thinking negative things about myself. Typically I think with memories, fictional situations, emotions or concepts. I’ve asked people in the past if their thoughts are internal dialog and more often than not, they said they were.
Note: I listed this under "Article" as I felt that fit better than any of the other categories. This is a short video discussing several scientific studies on this topic.
Topic: psychology
Relates to: deity work, shadow work, mindfulness
I was really surprised to learn that not everyone has inner speech. I wonder if this might explain why conversing with deity comes naturally to some while others find the idea bizarre. I also found it interesting that inner speech was associated with negative thoughts and feelings, as this definitely speaks to my experience. I use deity work as a way to reframe these internal conversations in a more positive way. I also think of it as part of my efforts to reparent myself, which ties in to the idea that inner speech is strongly influenced by how your caregivers treated you as a child. You may have heard the saying, "How you talk to your child becomes their inner voice"; perhaps this is more literally true than we thought! If we can change our inner speech, maybe we can reverse some of that damage. I definitely think so, but I also relate to the point mentioned in the video that even positive mental verbalizations can be a negative, or at least suboptimally positive, experience. Besides the discomfort of rehashing past traumas and ongoing inner struggles, I think maybe inner speech makes humans sad because we're just not meant to be cooped up in our own heads all that much. It's not enough to perceive the world solely through the abstraction of words, we want to actually be in the world, experience things firsthand and fully, with all of our senses.
The auditory aspect of inner speech also interests me. I'm fairly certain that I don't hear words aloud when I read silently; my brain goes straight from the visual representation (the printed word on the page) to the meaning without the auditory component. When I try to actually hear the words, I read much slower. But I'm not sure if I really "hear" my inner speech or not. It's definitely not a real, recognizable voice, as I can distinguish between particular voices (like imagining a certain accent or character's voice) and the default voice of my inner speech. If it is an actual, auditory voice, I think it must be a voice that does not exist anywhere in external reality, which is a pretty bizarre thought.