Schizophrenia and Affective Disorders

• When is schizophrenia most prevalent?

  often occurs during adolescence and more in males
• What is schizophrenia?

  A mental disorder characterized by abnormal social behavior and a distorted perception of reality, considered a type of psychosis
• What are postitve symptoms of schizophrenia?

  • something you gain
  • e.g. hallucinations and delusions
• What are negative symptoms of schizophrenia?

  • something you lose
  • e.g. anhedonia, social withdrawal
• What are the cognitive symptoms of schizophrenia?

  • general symptoms
  • poor problem solving, attention, memory, abstarct thinking
• What is the difference betweeen hallucinations and delusions?

  • hallucination= error in perceptions
  • delusion= error in belief
• What are the 3 types of delusions?

  • Persecution = government is following them
  • grandeur = I’m Jesus, etc.
  • Control = they’re being controlled (e.g., by a microchip)
• What is the main neurological symptom of schizophrenia?

  ventricles of patients with schizophrenia are approximately 130% the size of normal controls
• What other physical anamolies appear in schizophrenia?

  fine hair, malformed ears, furrowed tongue
• What causes schizophrenia?

  possible link with genetics (polygenic, predisposition) and environmental factors
• Is schizophrenia heritable?

  yes, shown in twin studies to have strong genetic link
• What did Davis et al show about the pre-natal environment effects?

  • Monochorionic concordance = 60%
  • Dichorionic concordance = 10.7%
  • shows pre-natal environment can have an effect
• What envronmental factors cause schizohrenia?

  cannabis, prenatal infection, birth month, chronic stress
• What is the dopamine hypothesis of schizophrenia?

  suggests that an overactivity of dopamine(almost double) in certain brain regions like the midbrain is responsible for the symptoms
• Why do dopamine agonists induce positive symptoms?

  • midbrain (including nucleus accumbens and amygdala) is high in dopamine
  • high dopamine in amygdala prompts delusion and impaired emotion regulation → leads to positive symptoms
  • high dopamine neurons in the accumbens strongly reinforce behaviour → positive symptoms are reinforced
• What did Fibiger (1991) find about paranoid delusions?

  caused by activity in the amgydala
• What did Snyder (1974) find about schziphrenic episodes?

  Schizophrenics report elation at the start of a schizophrenic episode
• What is the NDMA theory?

  • Glutamate hypoactivity in regions involved with cognition and executive function (e.g., prefrontal cortex) in people with schizophrenia
  • not just dopmaine involved
• What is the serotonin theory?

  • Serotonin dysfunction may disrupt typical cognitive abilities prompting the SCZ development
  • not just dopmaine involves
• What non-medication treatments can be used for schizophrenia?

  CBT, art-therapy
• What are affective disorders?

  Categorised as a mood disorder, identified by disruptions in emotions
• Why is schizophrenia not an affective disorder?

  Because schizophrenia is characterized by disturbances in thought, perception, and behavior, while affective disorders primarily involve disturbances in mood
• What are the primary symptoms of ADs?

  • mania- euphoria, delusional, poor attention span, lack of sleep, grandeur
  • depression- low energy levels, anhedonia, loss of appetite for food and sex, sleeping problems
• What are the nuerological and physical symptos of ADs?

  • currently unclear
  • no consistent neurological markers across conditions
• What is bipolar disorder?

  AD, Alternating periods of mania and depression, affects 1% of population
• What is unipolar disorder(MMD)?

  AD, depression without mania, more likely in women
• What is seasonal affect disorder (SAD)?

  Depression typically associated with the onset of winter months
• What are the causes of affective disorders?

  Genetic, environmental, and biological factors
• What studies demonstarte its heritability?

  • Gershon et al., (1976) – MZ concordance = 69%, DZ concordance = 13%
  • Price (1968)- Concordance is the same whether MZ twins are raised apart or together, strong genetic factor
  • Rosenthal (1971) – 10 times more likely to suffer from affective disorders if a close relative also does
• What is the monoamine hypothesis?

  • monoamine neurons are NT modulators
  • Suggests depression is caused by faulty activity on monoamine neurons
• How do faulty monoamines affect serotonin?

  Deficiencies in serotonin (thought to play a role in modulating mood)
• How do faulty monoamines affect norepinephrine?

  Norepinephrine imbalance (Plays a role in the bodies stress response)
• How do faulty monoamines affect dopamine?

  Dopamine dysfunction (Plays a role in reward and pleasure pathways)
• What drugs can be used to treat affcetive disorders?

  Tricyclics, SSRI's, iproniazid
• What non-medication treatments can be used for ADs?

  CBT, art therapy, light therpay