Tuning out our internal voices

Hearing voices is normal, says Swinburne’s Professor Susan Rossell. But sometimes those voices can cause extreme disruption.

Susan suspects our brain’s ability (or inability) to tune out our internal voice may be involved in the auditory hallucinations experienced by many with schizophrenia.

She’s using powerful new imaging technology to study why some people hear voices (looking at what happens inside the brain just before the onset of voices) and what can be done to help them manage it.

“We all have internal dialogue but we can choose to listen to our thoughts or not to listen to our thoughts,” Susan says.

Her previous work has shown that this internal dialogue activates the same regions of the brain—the language processing centres—as when someone real is talking to us. Most people can tune this voice out, along with all the other superfluous sounds we’re constantly exposed to, such as traffic noise or other conversations.

“We think people who hear voices can’t correctly filter out the noise in the world around them, and included in that noise is their own internal dialogue.”

Her colleagues Associate Professor Neil Thomas and his PhD student Imogen Bell are using smartphones to look at what might be happening outside the brain at that same moment.  

Susan has also identified people with no other signs of mental illness, but who experience voices at a similar intensity to people who have other manifestations—and their voice-hearing is often a positive experience.

“Some people describe them as like their guardian angel,” Susan says.

“It’s a voice that helps them make decisions, guides them, or gives them good advice.”

Banner image credit: Eamon Gallagher