Chapter 14 - Psychological Disorders

• This chapter covers the symptoms and theories behind a number of psychological disorders. Some things mentioned may be disturbing to some students.
• Diagnostic and Statistical Manual of Mental Disorders

  5th edition
• Incidence


  Number of individuals that develop a condition across a specific amount of time (usually a year)
• Prevalence


  Total count (or percentage) of people with a condition at a specific point in time
• Schizophrenia


  • Debilitating disorder characterized by perceptual, emotional, and intellectual deficits
  • Loss of contact with reality
  • Inability to function in life
• Psychosis


  Severe disturbances of reality, orientation, and thinking
• Schizophrenia


  • Coined by the Swiss psychiatrist Eugen Bleuler in 1911
  • Combination of Greek words meaning "split mind"
  • Combination of several symptoms: hallucinations and delusions, disorganized thought and social withdrawal, inappropriate emotions or lack of emotion
• Acute symptoms


  • Develop suddenly and are typically more responsive to treatment
  • Prognosis is reasonably good despite brief relapses
• Chronic symptoms


  • Develop gradually and persist
  • Poor prognosis
• Incidence of schizophrenia is higher among the relatives of people with schizophrenia than it is in the general population
• Schizophrenia is a familial disorder
• Concordance for schizophrenia is three times as high in identical twins as in fraternal twins
• Heritability of schizophrenia is likely around 0.80 overall
• Adoption studies show that an environmental change provides little or no protection against schizophrenia
• First degree relative of someone with schizophrenia is 13 times more likely to develop schizophrenia
• Family history is a better predictor of schizophrenia than any other factor
• Schizophrenia is likely caused by the cumulative effects of multiple genes with a modest individual effect
• Vulnerability model


  Model of schizophrenia that asserts some threshold of causal forces must be exceeded for the illness to occur
• Positive symptoms of schizophrenia


  • Delusions
  • Hallucinations
  • Thought disorders
  • Movement disorders
• Negative symptoms of schizophrenia

  • Avolition/Apathy - lack of initiative to accomplish purposeful tasks
  • Alogia - inability to speak
  • Anhedonia - inability to feel pleasure
  • Affective Flattening - lacking full range of emotional expression
  • Asociality - lack of motivation to engage in social activities
• Dopamine hypothesis


  Theory that schizophrenia involves high dopamine activity
• Aberrant salience hypothesis


  Suggests that heightened levels of dopamine increase attentional and motivational circuits to make ordinary environmental features seem significant
• Dopaminergic drugs are ineffective in many cases of schizophrenia
• Tardive dyskinesia is a side effect of long-term blocking of dopamine receptors
• Neuroleptics


  Atypical or second-generation antipsychotics that block receptors less strongly and target other, non-dopamine receptors
• Glutamate theory


  • Hypofunction of NMDA receptors > increases in glutamate > increases in dopamine
  • Produce positive and negative symptoms of schizophrenia
• Malfunctions occur in virtually every part of the brain in schizophrenia
• Schizophrenia is associated with brain tissue deficits and ventricular enlargement
• Schizophrenia is associated with hypofrontality on the Wisconsin Card Sorting Test
• Schizophrenia is associated with anomalies in neural connections and synchrony
• Schizophrenia is associated with environmental origins of brain and transmitter anomalies
• Schizophrenia is associated with a winter birth effect
• Schizophrenia is considered a developmental disease
• Affective (mood) disorders


  Include depressive disorders and mania
• Depressive disorders


  Include reactive depression and major (unipolar) depressive disorder
• Mania


  Requires three or more symptoms such as inflated self-esteem, decreased sleep, talkativeness, racing thoughts, easily distracted, increased goal-directed activities, agitation, and excessive involvement in risky activities
• Bipolar I disorder


  Alternate between periods of depression and full-blown mania, often including psychotic features
• Bipolar II disorder


  Alternate between periods of depression and hypomania
• Variability in bipolar disorder symptoms, especially mania:depression cycles, is due to increased sensitivity to dopamine and either decreased sensitivity to serotonin or more general dysregulation of the dopaminergic system
• Affective disorders are at least partly heritable, with a concordance of about 69% in identical twins compared to 13% in fraternal twins