• Dopamine and Serotonin are two neurotransmitters that are important in psychosis
  
• ( In reality, it is much more complicated than this, as there are more than 100 different neurotransmitters)
  
• In people with psychosis, the balance between these chemicals is disturbed
  
• One theory, is that in psychosis there may be too much Dopamine
  
• Excess dopamine causes an overstimulation of the nerves. This means that too many messages are being sent at the same time.
  
• Symptoms of psychosis, like Hallucinations and odd beliefs ( Delusions ) are thought to be related to this overstimulation
  
• When the brain is overstimulated for a prolonged period, it causes the nerve cells to shut down
  
• Symptoms of poor concentration and reduced motivation, may be related to this shut down
  
• The treatment of psychosis involves medications that work to restore the chemical balance in the brain
  
• They work by "mopping up" the excess Dopamine
  
• Treatment also involves managing stress and restoring the balance in the person's environment

More information is available on the 'Secret Life of the Brain'- This site includes much of the content of the PBS television special the Secret Life of the Brain. The graphics for the action of dopamine and the anatomy of the brain are excellent. Also talks about the impact of drugs on the brain.