Schizophrenia may blur brain boundaries

BOSTON, Jan. 23 (UPI) -- Schizophrenia may blur boundaries in the brain, causing an exaggerated focus on self, U.S. researchers suggest.

A brain imaging study by researchers at the Massachusetts Institute of Technology and Harvard University found schizophrenia may blur the boundary between internal and external realities by overactivating a brain system that is involved in self-reflection -- thus causing an exaggerated focus on self.

The traditional view of schizophrenia is that the disturbed thoughts, perceptions and emotions that characterize the disease are caused by disconnections among the brain regions that control the different functions.

However, the study published online ahead of print in the Proceedings of the National Academy of Sciences, found that schizophrenia also involves an excess of connectivity between the so-called default brain regions, which are involved in self-reflection and become active when we are thinking about nothing in particular, or thinking about ourselves.

"People normally suppress this default system when they perform challenging tasks, but we found that patients with schizophrenia don't do this," John D. Gabrieli, a professor in the McGovern Institute for Brain Research at MIT and one of the study's 13 authors, said in a statement.

"We think this could help to explain the cognitive and psychological symptoms of schizophrenia."