dopamine

• What does the dopamine hypothesis state about the brains of schizophrenic patients?

  Schizophrenic patients produce more dopamine than normal brains. (evidence from: PET scans, drug studies and post mortem evidence)
• What role do neurotransmitters play in the brain?


  They act as messengers transmitting impulses between nerve cells.
• What is the effect of elevated dopamine levels in the brain of a schizophrenic patient?

  Dopamine receptors fire too often or fail to bind properly, causing excessive dopamine activity.
• Which recreational drugs are mentioned to increase dopamine levels?

  Amphetamines and Cannabis
• What can large quantities of recreational drugs lead to in non-sufferers of schizophrenia?

  Delusions and hallucinations
• What happens to the symptoms of schizophrenic patients when they are given recreational drugs?

  Their symptoms get worse.
• What is the dopamine level in Parkinson's disease sufferers?

  Low levels of dopamine
• What effect does L-dopa have on dopamine activity in Parkinson's patients?

  raises dopamine activity.
• What can happen to Parkinson's patients if they take too much L-dopa?


  They may develop schizophrenic symptoms.
• What are phenothiazines used for in relation to schizophrenia?


  They reduce dopamine levels and relieve positive symptoms of schizophrenia.
• What did Falkai et al. (1988) find in their autopsies related to schizophrenia?


  People with schizophrenia have a larger number of dopamine receptors.
• What conclusion did Falkai et al. (1988) reach regarding dopamine production in schizophrenics?

  Dopamine production is abnormal in schizophrenics.
• What did Gjedde and Wong (1987) find regarding dopamine receptors in schizophrenics?


  There are more than twice as many dopamine receptors in schizophrenics compared to controls.
• What did Farde et al. (1990) conclude about dopamine receptors in schizophrenics?


  There is no difference in the number of dopamine receptors between schizophrenics and controls.
• What is the relationship between faulty chemicals and schizophrenia?

  • Faulty chemicals may cause schizophrenia.
  • Schizophrenia may also cause faulty chemicals.
  • Cause and effect is uncertain due to drug influence on other systems.
• How can genetic explanations be combined with the dopamine hypothesis to understand schizophrenia?

  • Genetic vulnerability may lead to schizophrenia.
  • Genetic factors can result in biological differences.
  • Abnormal levels of dopamine may be a neural correlate of schizophrenia.
• •There is a lack of correspondence between taking the drugs and

  signs of clinical effectiveness.


  It takes 4 weeks to see any sign that

  the drugs are working when they begin to block dopamine

  immediately. We can not seem to explain this time difference.
• Type 1 cases respond well to conventional anti-psychotic drugs.


  Drugs such as CHLOPROMAZINE: Only effective at relieving the

  Positive Symptoms of the Illness.
• Not good at explaining negative symptoms.


  suggested that type 2 is related to a different kind of abnormality such as brain structure