The Mind Without an Inner-Monologue
Researchers are calling it anendophasia
Hiya!
You have an inner monologue if you hear these words spoken in your head as you read them. This inner voice is also known as your self-talk or inner speech. If you have one (or many), you’re probably like me and most other people who assumed everybody does.
Yet research suggests our inner voices vary widely. Some people hear a near-constant chatter, while others’ inner voices are practically absent; some people have one voice, and others have many. This revelation is so new that researchers haven’t cemented a term for it, though some call it anendophasia.
What is Inner Speech?
We all know thoughts are unique to each individual, but so is how we experience them. The internal experience of many people, myself included, contains a verbal quality that can best be described as an inner voice or inner monologue — it’s a verbal language that doesn’t require the mouth to “speak” and is “heard” only in the mind, not with the ears.
Children typically develop an inner monologue around the age of 2 or 3, around the time they develop expressive language, including verbal and nonverbal communication.
This inner speech is private and not audible to anyone else. Not only are we the only ones who can “hear” our inner monologues, but how they present, including their tones, inflections, and frequency, is unique to us.
For instance, I have a multilayered and diverse community of inner voices in my mind. Most “sound” like me, but each has a distinct cadence, tone, vocabulary, and volume. I also hear the voices of people I know, like things my Dad said while he was alive. Meanwhile, a woman with no Italian ancestry reports that her inner-speech presents as a bickering old Italian couple.
Still, researchers have identified three primary aspects of the inner speech experience.
The first dimension of inner speech is condensation, which refers to how concise a person’s inner voice is. Some people’s inner voices, mine included, use complete sentences, even paragraphs, while others may only use a sentence, a word, or even a fragment of a word.
The second is dialogality, which pertains to whether a person thinks in one or multiple voices. I don’t know precisely how many voices I use to think with, but there are a lot of them, and each has a distinct purpose. But some people think in only one or a couple of voices.
The third primary dimension of inner speech is intentionality. In other words, when a person deliberately uses their inner voice, like to practice a presentation or rehearse a conversation. Meanwhile, a person’s inner voice may be active without conscious intention, such as while daydreaming or when their mind wanders.
Researchers are understandably fascinated with learning more about the inner speech experience — especially now that technological advancements allow them to study it. In addition to the versatility of how inner speech is presented in people’s minds, researchers also want to know about any cognitive effects and functions related to having and not having inner speech.
Famira Racy, an independent scholar who co-founded the Inner Speech Research Lab at Mount Royal University in Calgary, Canada, explained to Simon Makin of Scientific American:
“Past research suggests inner speech is key in self-regulation and executive functioning, like task-switching, memory and decision-making. Some researchers have even suggested that not having an inner voice may impact these and other areas important for a sense of self, although this is not a certainty.”
The good news is that while still in its infancy, research about inner speech is already teaching us plenty.
How common is it?
If you’re like me, the first question you have when learning that some people experience, or don’t experience, inner speech is how common or uncommon it is. Unfortunately, it’s a tad challenging to determine a precise estimate because it’s not exactly easy to study.
Beyond the fact that inner speech is diverse and likely unique to each person, it’s also a subjective experience — and subjective experiences are tricky to study using objective study methods. Of course, that hasn’t stopped researchers from trying.
Over time, researchers have devised different ways to study inner speech, including experience sampling, in which participants are interviewed about their experiences or asked to keep diaries they turn in. Russell Hurlburt, a professor of psychology at the University of Nevada, Las Vegas, developed a popular experience sampling method called Descriptive Experience Sampling in the 1970s, which has been used and continually updated ever since.
Other methods for studying inner speech include questionnaires and self-report surveys. Still, it’s hard to know for sure whether what people report as their experiences is what’s actually going on. Charles Fernyhough, a psychologist at Durham University in England, explained to Makin:
“It’s very difficult to reflect on one’s own inner experiences, and most people aren’t very good at it when they start out.”
Many people analyze the contents of their thoughts, but most don’t pay attention to how they experience thinking. This means that despite researchers' best efforts, investigations into inner speech have inconsistent results. It also means researchers have a broad range of how common inner speech is.
Using his Descriptive Experience Sampling method, which requires research participants to report their inner experiences at random times throughout the day, Hurlburt estimates that between 30 and 50 percent of people frequently experience an inner voice. His research indicated that most people’s inner speech doesn’t talk (for lack of a better word) all the time and that many people go through long portions of their days without experiencing their inner voice.
Meanwhile, other research methods lead researchers to believe people experience inner speech far more frequently. One study suggests people experience their inner voice(s) 75 percent of the time. Ultimately, more research is needed before experts can narrow their estimates.
Besides, there’s plenty more to learn about inner speech beyond how many people experience it. For instance, how does inner speech present in and affect the brain?
New Research
A new study by cognitive scientists Gary Lupyan at the University of Wisconsin–Madison and Johanne Nedergaard at the University of Copenhagen is the first to show that a lack of inner speech affects some aspects of cognition.
The researchers asked two groups of study participants to accomplish four simple, language-based tasks. One group included 47 people who scored high on the Internal Representations Questionnaire (IRQ), suggesting they had strong inner speech experiences, while the other group of 46 participants scored the lowest on the IRQ, suggesting they had fewer inner speech experiences.
For the first task, the participants were shown five words and asked to repeat them back. The second task was for participants to say whether the names of two objects in a picture rhymed. These tasks may seem simple, but the group with less inner speech was less accurate in both experiments and slower to respond in the rhyming one.
The researchers wanted to understand the participants’ internal experiences, so they asked the participants if they spoke aloud during the first two tasks. A similar proportion of the two groups reported that they had spoken aloud, and when the researchers compared only those participants, the differences between the two groups disappeared. In other words, speaking aloud may compensate for lacking inner speech.
The third task involved task switching, when we mentally shift our attention from one task or thought to another. Previous research suggests people use inner speech to direct themselves in task switching.
The fourth and last test involved the participants identifying differences between silhouettes from the same or different categories — like two dogs versus a dog and a cat — since language influences labels and categories.
The researchers found no major performance differences between the two groups during the third and fourth tasks. They believe this may be because there are many other helpful strategies for assisting people in these tasks. Jupyan explained to Makin that using fingers can help people keep track of tasks and that inner speech may not be useful for visual judgments like comparing silhouettes.
Overall, the participants with stronger inner voices did better at psychological tasks that involved verbal memory than those with weaker inner voices.
This study is just the beginning, and more research is definitely needed. However, boosting research focused on inner speech, or lack thereof, is challenging without an official term. This is why Lupyan and Nedergaard propose naming it anendophasia, from the Greek words an meaning “lack,” endo meaning “inner,” and phasia meaning “speech.”
As exciting as the new study is, many mysteries remain. Beyond pinpointing a more precise estimation of how common or uncommon inner speech is, there’s also the question of why inner speech evolved at all.
How Does Having or Not Having Inner Speech Impact Us?
While scientists continue to study the mechanisms of inner speech, they’ve already discovered a range of benefits and disadvantages to the trait.
Researchers have found that the benefits of experiencing inner speech cover many domains, including emotional regulation, perspective-taking, planning, problem-solving, self-reflection, and self-regulation. Inner speech can also be used as a source of motivation and positive self-reinforcement — a new take on the saying, “Be your own biggest cheerleader.”
On the flip side, some people’s inner speech tends to be more critical, which can create or exacerbate mental health stress. Critical self-talk is linked with lower self-esteem, and people say negative statements about themselves more frequently. After all, the last thing anyone needs is for their own inner voice to make them feel worse than they already do.
Inner speech is tricky to study, but it’s easier with participants who have it than those without, which is why research regarding why some people don’t have inner monologues is severely lacking.
However, scientists found at least one way — by comparing people without inner speech to people with aphantasia, the inability to see visual images in one’s mind (We’ll discuss it more on Monday in Curious Life.)
A 2021 study discovered that people with aphantasia also had weak or non-existent inner monologues as well. In other words, these people don’t see images or hear voices in their minds when they think or imagine. The researchers from the University of Auckland, New Zealand, named this mind experience “anauralia.”
On the other hand, the same study showed that the opposite was also true. Participants with vivid visual imaginations typically experienced vivid inner monologues, too.
Again, more research is needed before scientists know whether the inability to visualize in one’s mind influences whether someone has an inner monologue or vis versa.
However, nothing says we have both inner speech and inner sight or neither. As I said, my inner speech is rich and multi-layered. My inner voices are talkative and generally positive, but I can usually turn them off or change the narrative when necessary. My inner sight, however, is nearly non-existent. I struggle to imagine anything my eyes haven’t seen, and even then, the images are fragmented, or it’s like looking through a window covered in condensation.
In the Future
Researchers hope to learn more about inner speech and establish just how broad the inner speech spectrum is. Fernyhough told Makin that he and his colleagues want to find out whether a total absence of inner speech actually exists.
The inner speech spectrum doesn’t just range from one to many voices or from quiet to loud but includes many other variables too. Fernyhough explains:
“Our inner experience can differ from moment to moment, depending on what we’re doing. Our work has shown that inner speech varies along a range of reliable dimensions.”
Some of these inner speech dimensions include its emotional quality and how condensed or conversational it is. Fernyhough says:
“The interesting question for the future is whether certain kinds of inner speech can help us solve particular cognitive challenges, rather than simply how much is going on overall.”
Scientists also want better to understand the possible medical implications of inner speech. Lupyan told Makin:
“Someone with more inner speech might be more reliant on language in their thinking. So language impairment from stroke could have a more severe effect, and they may benefit from different treatments.”
Education is another area researchers want to explore since inner speech development may influence children’s learning abilities. A neuroscientist at the Paris Brain Institute, Ladislas Nalborczyk, told Makin:
“Variations in children’s ability to represent speech sounds may impact the ability to learn the relation between sounds and writing,” which in turn “may impact the way they learn to read and write, which probably has tremendous impact on their education.”
Perhaps the most important work to be done, before anything else, is to find ways to measure inner speech differences objectively. Researchers hope technology like magnetic resonance imaging (MRI) brain imaging will help.
Nalborczyk explains that such technology can help experts better understand what’s happening in the brain while participants are engaged with their inner voices.
“You can try to decode from brain signals if a participant is hearing a voice, what kind of voice, and so on. That would be the logical next step.”
Perspective Shift
Thanks to technological and scientific advances, scientists can finally tackle some of humanity’s longest-held mysteries, such as studying the inner workings of our brains and minds. We all know that every human has a unique body and life experiences that shape us into distinct individuals. You are the only person who will ever truly know what it’s like to be you. We all know this on some level, yet we spend most of our lives assuming other people literally think like we do.
We may have different experiences, and the content of our thoughts may change, but we all have brains and assume they work the same way for everyone. But the truth is, in some ways, our brains are as unique as we are — as too are our minds. Research shows thinking and imagination are unique to each of us. Some people can “see” in their minds while others cannot, and now we know some people “hear” in their minds while others do not.
Ultimately, discovering so many ways people think — anendophasia, anauralia, aphantasia, synesthesia, and likely more — shows that we’re as diverse on the inside as we are on the outside.
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Excellent article about an issue I’ve wondered about - silently - for years. When I’ve asked others about their mind’s inner sounds, most don’t know. I have a different version of what you are writing about. I don’t hear words, I hear music, pretty much constantly, starting when I wake up. It’s like a radio. A song will persist for a long while, and then suddenly I realize the song has changed. It’s not unpleasant in the least, and it doesn’t interfere with my use of language (talking, writing, reading). The only problem is when - LOL - I don’t like the song. Anyway, thanks for a great read (accompanied by a rock song from the 1980’s).
Fascinating! I wonder how these inner voices tend to differ in men vs. women, in meditators, people with multiple personalities, those who are more left-brain vs. right-brain oriented, and more. And should we seek to enhance or diminish this function to improve outcomes? Could there be a genetic predisposition? The possibilities for future research appear to be vast.