Researchers Discover How the Brain "Creates" Words Before We Speak Them

A new study, published in Nature, delves into the complex mechanisms of the human brain during the planning and production of speech. Conducted by researchers from the Massachusetts General Hospital (MGH), it employs probes to identify specific neurons in the prefrontal cortex, thereby unveiling the intricate activity employed by the brain to successfully speak and listen.


In this study, the team used Neuropixels probes to record the activity of individual neurons involved in the planning and production of speech. The findings reveal distinct groups of neurons dedicated to speaking and listening, as well as how the brain constructs the sounds of speech before they are uttered.

Dr. Ziv Williams, an associate professor of neurosurgery at MGH and Harvard Medical School, points out that despite the apparent ease of speech, our brain actually carries out complex cognitive steps at an astounding speed.

By using advanced recording techniques, the researchers have indeed identified that neurons work together to allow the mind to choose the words to say and pronounce them out loud. The researchers found that some neurons become active before the emission of a phoneme, while others reflect complex aspects of word construction.

Thus, for instance, the sound "de" requires placing one's tongue against the roof of the mouth. Even before the individual becomes conscious of the movements they are about to make to pronounce this word, neurons dedicated to this activity are busy preparing all the actions that will be necessary. With the help of the probes, the scientists were able to reliably predict speech sounds before they were articulated.

The co-author of the study, Arjun Khanna, highlights that understanding the basic neuronal connectivity for speech and language could pave the way for treatments for a wide range of neurological disorders.

This research challenges our understanding of the neural bases of speech, also offering perspectives for the treatment of speech and language disorders. Moreover, it paves the way for the development of technologies for synthetic speech production, a ray of hope for those affected by neurological disorders impairing communication.