What disrupts brain in psychiatric disorder

Researchers have identified how over-activation of certain brain chemical receptors trigger disruption in the brain's communication channels linked to symptoms in psychiatric disorders, including schizophrenia.

The findings could have important implications for treating symptoms of brain disorders.

Many of our everyday cognitive functions such as learning and memory rely on normal communication between the two regions of the brain - the hippocampus and prefrontal cortex.

While previous studies have identified disruption to communication channels in these two areas of the brain contribute to symptoms in psychiatric disorders, the mechanisms that lead to these disturbances have been largely unknown, until now.

In this study, led by professor Zafar Bashir from University of Bristol in England, the researchers studied neurotransmitters, called glutamate and dopamine, which work together in controlling normal transmission between these brain regions by communicating chemical information throughout our brain and are disrupted in schizophrenics.

The team found that subtle changes in the interplay of these transmitters completely altered the flow of information from the hippocampus to prefrontal cortex.

Over-activation of dopamine receptors can led to suppression of the function of certain receptors known as N-methyl-D-aspartate (NMDA), which are activated by the neurotransmitter glutamate.

This in turn leads to a marked disruption of communication between the brain regions hippocampus and prefrontal cortex, the researchers found.

"Our findings demonstrate a mechanism for how dopamine neurotransmission can influence NMDA receptor function at a connection in the brain needed for complex mental tasks which are disrupted in schizophrenic patients," one of the researchers Paul Banks from University of Bristol pointed out.

The study was published in the journal Proceedings of National Academy of Sciences.