To the Brain, Reading Aloud is the Same as Reading to Yourself

What happens when we make the switch from reading aloud to internalizing our voices? Carl Engelking from Discover Magazine summarized a study published in the Proceedings of the National Academy of Sciences that sought to answer just this question. The results of the group’s research found that the brain lights up the same way when we read to ourselves as it would when we read aloud, showing what an important role sound plays to developing our internal monologue.

The researchers recruited 12 men and four women for this study, all of whom were having surgery to remove malignant tumors. The surgery was used to also attach electrodes to the participants’ Broca area of the brain, which is responsible for functions related to speech production. Participants remained conscious in order to conduct the test, using local anesthesia to dull the pain.

After the electrodes were attached the first part of the test could begin. Researchers asked the participants to read aloud some phrases and words while they measured sound waves and electrical signals produced by the brain. In the second part of the test researched asked participants to silently read the same words and phrases from the previous part.

The results produced an interesting find: the participants’ brains mimicked the sound frequencies as if the words were being read aloud.

The researchers write:

“This suggests that in hearing people, sound representation deeply informs generation of linguistic expressions at a much higher level than previously thought. This may help in designing new strategies to help people with language disorders such as aphasia.”