Can You Replay Conversations In Your Head? If Not, You Might Struggle With These Common Tasks

Think of the last conversation you had. What did you say? What did they say? Did you hear any of what you were about to say in your head first? If not, you may be part of the (internally) silent minority of people who lack an inner voice. Recent psychology research has revealed that — despite past assumptions — not everyone has a narrator yakking it up in their brain. Some people picture ideas and others more nebulously report thinking in “concepts.” These differences can have consequences — potentially leading to difficulty with some verbal tasks.

The primary finding of a study published May 14 in the journal Psychological Science is that those without mental dialogue may have worse verbal memories. Not everything hinges on internal voice, however. The new findings indicate there are ways to compensate for a quiet mind and that the presence or absence of an inner narrator doesn’t have bearing on all cognitive tasks.

For the study, the researchers recruited 93 online participants who responded to a questionnaire about the format of their thoughts. Most people (somewhere between 90 and 95 percent) reported having some degree of inner voice, but the study sought to compare those who do and don’t. About half of the participants included in the study were those with “low verbal factor” scores, while the other half had relatively high verbal factor scores. Both groups were balanced for age, gender, education level, dyslexia, and first language.

“There are real behavioral consequences of experiencing more or less inner speech.”

In a series of different tests meant to suss out the behavioral impacts of presence or absence of inner voice, the researchers found some significant differences between the two groups. In one task, participants were shown images of two objects simultaneously and asked to identify if the words for those objects rhymed or not. Those with lower verbal factor scores were less accurate in assessing rhymes. In another test, study subjects were asked to memorize lists of five given words and write them out. Again, those with less of a self-reported inner voice were less accurate in reproducing the words.

“Taken together, our experiments suggest that there are real behavioral consequences of experiencing more or less inner speech,” write the study authors in their paper.

Yet in both of these experiments, the researchers found that speaking aloud canceled out the difference between the participant groups. When those with low verbal factor scores reported talking out loud to themselves during the tests, they performed just as well as those who reported having inner dialogue, suggesting there are common and effective ways of compensating for a lack of inner voice. “Maybe people who don’t have an inner voice have just learned to use other strategies,” Johanne Nedergård, co-author of the study and a linguistics researcher at the University of Copenhagen, said in a press release.

It’s also unclear if these experiments carry any real-world implications.

And in two of Nedergård and her co-author’s experiments, differences in inner voice didn't seem to matter. In one task where people were asked to categorize images of cats and dogs, there was no significant performance difference between the test groups. In another where participants were asked to switch between adding and subtracting numbers, there was also no significant difference in accuracy. That’s despite the fact that previous research indicated these sorts of tests might be more difficult for those without an inner voice.

The researchers note that self-reported questionnaires are a subjective measure of peoples’ thoughts, and it’s possible that participants were wrong about their inner experiences. But the fact that the authors found differences in some of their experiments suggests that something really is going on here. Nonetheless, much more research is needed to pinpoint exactly what that something is.

Although the tests revealed some small differences between groups, it’s also unclear if these experiments carry any real-world implications. “We just don’t know because we have only just begun to study it,” Nedergård said in the press statement. However, she hypothesized one area it might make a difference is in therapy. Cognitive behavioral therapy focuses on restructuring inner thoughts and patterns. For those lacking internal dialogue, she noted, the therapeutic strategy may not work the same way.