People suffering from the disorder and their healthy siblings share a brain “signature” that could help with early diagnosis and the development of new treatments, say researchers at the Federal Institute of Technology Lausanne (EPFL).

Schizophrenia, which usually first appears in adolescents and young adults, originates from many different genetic variants that cause the developing brain to go awry. This makes it difficult to detect who may be at risk of developing the neuropsychiatric disorder.

Scientists at the EPFL analysed the brain patterns of 101 people with schizophrenia, 43 of their unaffected siblings, and 75 healthy individuals with no family history of schizophrenia.

The team scanned the participants’ brains using resting-state electroencephalography (EEG). Their findings, published in the journal Nature Communications, reveal the same brain activity patterns for certain types of neuronal activity or EEG microstates – class C and class D specifically – in people with the disorder and their siblings but not in healthy participants.

However, a third type of microstate, class B, occurred more frequently and for longer periods in healthy siblings than in those with schizophrenia. This may explain why the siblings do not display symptoms of the disorder, despite sharing the same brain “signature” as their relatives with schizophrenia.

“This could be a protection mechanism that prevents the imbalance in microstates class C and D from creating functional problems,” said researcher Janir Ramos da Cruz.

Study co-author Michael Herzog said that looking for abnormal patterns in brain waves could help with early detection, before symptoms appear, and even inform personalised treatment and prevention strategies.