If you’re reading this article silently to yourself, do you hear an inner voice pronouncing the words? Many people report mentally imagining speech when they concentrate on reading something inwardly, and researchers are in the beginning stages of figuring out just what that means.
Scientists have recently conducted a unique study that observed an increase in the rate of electrical activity in the brain’s auditory cortex when subjects were tasked with reading silently to themselves. These stimulated sections of the auditory cortex, located on the temporal lobe, are the same areas that respond to speech, music, background noise, and – we’re now starting to think – the written word.
So I’m Not The Only Person Who Talks To Themselves?
Since this particular phenomena cannot be properly observed using fMRI alone, little research has been conducted. In order for scientists to get an in-depth visual of this activity, the subject must have electroencephalographic electrodes (EEG electrodes) implanted under their skull and above their temporal lobe. Because this is an uncommon procedure, the study included just four subjects diagnosed with a rare form of temporal lobe epilepsy who already had EEG electrodes implanted. In the study, each subject’s brain activity was monitored as they read a story silently to themselves. What resulted in all four participants was a spike in high-frequency electrical activity throughout the speech components of their temporal lobes; very similar to the electrical activity observed when the subjects listened to spoken instructions. This possibly means that our auditory cortex considers writing as speech, especially since it responds to it in the same way that it responds to hearing a spoken language.
The authors of the report on this study, “How Silent Is Silent Reading?” featured in the Journal of Neuroscience, 2012, believe these results are evidence that people hear an “inner voice” when reading to themselves.
Only If You Concentrate
Interestingly enough, these levels of electrical activity were only observed when the participants were concentrating on the task of silent reading. Since these electrical impulses were only noticeably enhanced when the subjects were paying attention, this might suggest that the “inner voice” may not be so mechanical or automatic, but occurs when we are attempting to actively process what we’re reading. So ask yourself, what do you “hear” as you silent-read this?