Do you hear your own voice in your head when you think, read, or remember information? For most people, having an inner monologue is a common experience that’s often taken for granted. However, recent research has revealed that not everyone shares this trait. Some individuals, it turns out, navigate their mental landscapes in near silence.
This phenomenon, dubbed “anendophasia” by researchers from the University of Copenhagen and University of Wisconsin-Madison, refers to the lack of an inner voice. Their landmark study, published in the journal Psychological Science, sheds light on the potential consequences of living without this internal narrator.
“Some say that they think in pictures and then translate the pictures into words when they need to say something,” says study author Johanne Nedergård, postdoctoral researcher and linguist at the University of Copenhagen. “Others describe their brain as a well-functioning computer that just does not process thoughts verbally, and that the connection to loudspeaker and microphone is different from other people’s. And those who say that there is something verbal going on inside their heads will typically describe it as words without sound.”
What does it mean to have a silent mind? Researchers set out to investigate whether the absence of an inner voice affects how people solve problems, particularly in the realm of verbal memory tasks. They conducted a series of experiments with participants who reported either a high degree of inner voice or very little inner voice in their daily lives.
One experiment focused on remembering sequences of words that were similar in sound or spelling, such as “bought,” “caught,” “taut,” and “wart.” Researchers hypothesized that this task would be more challenging for those without an inner voice, as they wouldn’t be able to repeat the words internally to aid in memorization.
“It is a task that will be difficult for everyone, but our hypothesis was that it might be even more difficult if you did not have an inner voice because you have to repeat the words to yourself inside your head in order to remember them,” explains Nedergård. “And this hypothesis turned out to be true: The participants without an inner voice were significantly worse at remembering the words.”
A similar pattern emerged in another experiment involving rhyming words. Participants were shown pairs of pictures containing words that either rhymed or didn’t, such as a sock and a clock. Once again, those without an inner voice struggled more with this task, as they couldn’t rely on their internal voice to compare the sounds of the words.
Researchers found no differences between the two groups in tasks involving rapid switching between different activities or distinguishing between very similar figures. This suggests that individuals with anendophasia may have developed alternative strategies to compensate for their lack of an inner voice.
“Maybe people who don’t have an inner voice have just learned to use other strategies. For example, some said that they tapped with their index finger when performing one type of task and with their middle finger when it was another type of task,” notes Nedergård.
While the differences in verbal memory identified in the study may not be noticeable in everyday conversations, Nedergård believes that the absence of an inner voice could have implications in certain areas, such as therapy.
“But there is one field where we suspect that having an inner voice plays a role, and that is therapy; in the widely used cognitive behavioral therapy, for example, you need to identify and change adverse thought patterns, and having an inner voice may be very important in such a process,” concludes Nedergård. “However, it is still uncertain whether differences in the experience of an inner voice are related to how people respond to different types of therapy.”
