Scientists Pinpoint Brain Signals Behind Voices in Schizophrenia.
A new study has uncovered key brain processes linked to the voices heard by people with schizophrenia.
Researchers found that one missing element is the brain’s ability to prepare the senses for upcoming speech, a process called corollary discharge. Normally, this helps us recognize our own voice and separate it from external sounds. In individuals with schizophrenia, this system is weakened, creating confusion between internal and external stimuli.
The study also revealed an overactive motor signal known as the efference copy, which increases internal “chatter” in the brain. When this heightened activity combines with impaired sensory preparation, it blurs the line between internal thoughts and external voices, leading to auditory hallucinations.
The findings, published in PLOS Biology, provide new insight into the neural basis of schizophrenia and how the brain generates these experiences.