A new study has revealed that movement and hearing are connected and can influence each other.
The findings suggested that disruptions in the communication between the brain's motor cortex, which controls movement, and the auditory cortex, which gives rise to our conscious perception of sound, might give rise to auditory hallucinations in people with schizophrenia.
The team found that movement stimulates inhibitory neurons that in turn suppress the response of the auditory cortex to tones.
David Schneider, a postdoctoral associate, said that their first step would be to start making more realistic situations where the animal needed to ignore the sounds that its movements were making in order to detect things that were happening in the world.
To find out whether movement was directly influencing the auditory cortex, researchers conducted a series of experiments in awake animals using optogenetics, a powerful method that used light to control the activity of select populations of neurons that had been genetically sensitized to light.
The effect of playing a tone on the auditory cortex was much the same as if the animal had actually been moving and then the result confirmed the importance of the secondary motor cortex (M2) in modulating the auditory cortex and on turning off M2 simulated rest in the auditory cortex, even when the animals were still moving.
The study is published in Nature.