Hallucinations linked to changed structures in brain

People diagnosed with schizophrenia who are prone to hallucinations are likely to have structural differences in a key region of their brain than healthy individuals and people with schizophrenia who do not hallucinate, says a new study.

"By comparing brain structure in a large number of people diagnosed with schizophrenia with and without the experience of hallucinations, we have been able to identify a particular brain region that seems to be associated with a key symptom of the disorder," said one of the researchers Jon Simons from the University of Cambridge in London.

The study found that reductions in the length of paracingulate sulcus (PCS), a fold towards the front of the brain, were associated with increased risk of hallucinations in people diagnosed with schizophrenia.

The PCS is one of the last structural folds to develop in the brain before birth, and varies in size between individuals.

In this study, the researchers analysed 153 structural magnetic resonance imaging (MRI) scans of people diagnosed with schizophrenia and matched control participants, measuring the length of the PCS in each participant's brain.

The researchers found that in people diagnosed with schizophrenia, a one cm reduction in the fold's length increased the likelihood of hallucinations by nearly 20 percent.

The effect was observed regardless of whether hallucinations were auditory or visual in nature.

The findings appeared in the journal Nature Communications.