The ability to filter and process information is vital for leading a normal life

Dr Tonmoy Sharma, Institute of Psychiatry

A breakdown in this filter might lead to "information overload" - and contribute to the confusion often experienced by schizophrenics during psychotic episodes.

A study carried out by the Institute of Psychiatry in London used magnetic resonance imaging (MRI) scans to look at the size of the thalamus in schizophrenics, compared to healthy volunteers.

The 38 schizophrenics taking part were all at an early stage of the disease - experiencing their first episode of psychosis.

Importantly, a significant number of them had no or little experience of taking anti-psychotic medication.

The study found the thalamus was smaller in the brains of the early schizophrenics, suggesting it may play a role in the development of the disease.

Dr Tonmoy Sharma, from the institute, suggested that the finding might help doctors spot the disease early, and could even contribute to preventive therapies at some point in the future.

He said: "This study reveals that there is a fundamental problem in the hub of the brain.

"If you think of the brain in terms of networks, it is like making a phone call when the line is not connected properly, the call can't be made, or you may get through to the wrong person.

"It is the same in the brain. If there are problems with the connections, information will not be passed to the correct regions. The ability to filter and process information is vital for leading a normal life."