Schizophrenia Flashcards
How much of the population does schizophrenia affect?
→ 1%
What gender is affected more?
→ men are more affected
What are positive symptoms in schizophrenia?
→ increase in abnormal behaviour in addition to normal behaviour
What are negative symptoms in schizophrenia?
→ absence of normal behaviour
What are cognitive symptoms in schizophrenia?
→ problems with thought processes
What are examples of positive symptoms?
→ hallucinations
→ delusions
→ disorganised thought/speech
→ movement disorders
What are examples of negative symptoms?
→ social withdrawal → anhedonia → lack of motivation → poverty of speech → emotional flatness
What are examples of cognitive symptoms?
→ impaired working memory
→ impaired attention
→ impaired comprehension
How long must symptoms last for?
→ 6 months
If an identical twin has schizophrenia what is the likelihood of the other twin having it?
→ 50%
What are 3 candidate genes for schizophrenia?
→ COMT
→ DISC1
→ GRM3
What are 4 pregnancy complications that can lead to schizophrenia?
→ low birth weight
→ premature birth
→ asphyxia
→ influenza
What are the 4 types of stress that can contribute to schizophrenia?
→ moving country
→ bereavement
→ loss of job/home/relationship
→ physical/emotional/sexual abuse
What kind of drug use can contribute?
→ cannabis
→ amphetamine
→ cocaine
→ LSD
What is the evidence for the dopamine hypothesis for schizophrenia?
→ DA is only released in mesocortical and mesolimbic not nigrostriatal
→ D2 agonists produce stereotyped behavior
→ Reserpine depletes DA and controls +ve symptoms
→ antagonist of the D2 receptor has antipsychotic effects
→ Amphetamine increases DA release in schizophrenics which makes the disease worse
What is the evidence against the dopamine hypothesis?
→ No change in DA receptors in drug free patients
→ No change in CSF HVA concentration
What are the 3 structural differences in schizophrenic brains?
→ brain is slightly smaller
→ grey matter is reduced
→ enlarged ventricles and smaller hippocampus
What are the 6 reasons that contribute to the pathophysiology of schizophrenia?
→ Dopamine hypothesis → Brain structure differences → Hypofrontality → NMDA receptor hypofunction → Oxidative Stress
WHat is hypofrontality?
→ Reduced blood flow to the frontal cortex → reduced activity
What is the evidence for the glutamate hypothesis?
→ NMDA antagonists (PCP and ketamine) cause hallucinations and psychotic symptoms
→ Decreased glutamate receptor density in the prefrontal cortex
→ transgenic mice have decreased NMDA receptors and have decreased social interactions