A new study led by psychologists from UNSW Sydney has provided the strongest evidence yet that auditory verbal hallucinations—or hearing voices—in schizophrenia may stem from a disruption in the brain’s ability to recognize its own inner voice.

In a paper published today in the journal Schizophrenia Bulletin, the researchers say the finding could also be an important step toward finding biological indicators that point to the presence of schizophrenia. This is significant, as there are currently no blood tests, brain scans, or lab-based biomarkers—signs in the body that can tell us something about our health—that are uniquely characteristic of schizophrenia.

Professor Thomas Whitford, with the UNSW School of Psychology, has been examining the role of inner speech in the cognition of healthy people and people living with schizophrenia spectrum disorders for some time.