What's happening in the brain?

Dopamine is one of many chemicals in the brain that are used to pass information from one brain cell (neuron) to another. It is a ‘neurotransmitter’. Most pleasurable experiences and most illicit drugs cause dopamine to be released in the brain.

The chemical also has a role in memory, attention and problem-solving and is involved in controlling movements (people with Parkinson's disease have too little dopamine).

Research has shown that too much dopamine in the brain can lead to hallucinatory experiences, delusions and disordered thoughts. Studies have also shown that people who are thought to be at risk of developing schizophrenia have increased levels of dopamine in their brain before they experience their first episode of psychosis.

Some scientists have suggested that dopamine is what they call the ‘final common pathway’ to psychosis – dopamine levels may rise for any one of a number of different reasons, but it is the increase itself that prompts the symptoms of psychosis, though the exact mechanism remains unknown.

Researchers think other neurotransmitters may also have a role in the development of psychosis and are carrying out studies to try to find out whether this is the case. If other neurotransmitters are somehow involved in the development of psychosis, new medications could be developed to target these other chemicals.

Researchers are particularly interested in the neurotransmitters glutamate and GABA. Glutamate stimulates the brain while GABA slows down its activity. Glutamate is involved in many brain functions, including thinking, memory and learning.

Dr Sukhi Shergill explains more here: