Physical activity – When we talk to ourselves, the body also moves
When a person talks to himself without being heard by others, he performs, without really realizing it, a very light physical activity.
We can very well manage to live without feeling the need to think. But at times, this action is necessary to, for example, simulate a discussion to come with an important interlocutor. It is then a question of “inner speech”, and about a century ago, it had been revealed that these words spoken to oneself were accompanied by slight movements at the level of the larynx. Probably not enough to meet the demands of regular physical activity, but significant all the same.
Areas active during both spoken speech and inner speech
In the 1990s, writes The Guardian, a use of functional neuroimaging demonstrated that areas such as Broca’s area, associated with the production of spoken words, were active not only during spoken speech, but also during speech of an inner discourse.
A Finnish study on the differences
In an effort to better understand how inner speech works, Finnish researchers used functional magnetic resonance imaging (fMRI) to measure brain activity in two specific situations. In the first, the subjects of the experiment were subjected to an auditory verbal hallucination, and in the second, deliberately thought they heard the same voice.
A cortical region that did not react in the same way
The major difference between the two cases was located in a cortical region called the supplementary motor area (SMA). The AMS, which governs movement, experienced significantly less activity when participants heard voices. An observation which tended to validate previous hypotheses as to signals emitted by the motor cortical areas and which would have an impact on the fact of recognizing an action like his.
