Depression : Predisposing factors

Predisposing factors

  • Biological factors
    • Genetics
      • A growing body of knowledge indicates that genetics plays an important role in the development of schizophrenia.
    • Biochemical factors
      • One theory suggests that schizophrenia may be caused by an excess of dopamine activity in the brain.
      • Abnormalities in other neurotransmitters have also been suggested
  • Physiological factors
    • Viral infection
    • Anatomical abnormalities
    • Electrophysiology
    • Epilepsy
    • Huntington’s disease
    • Birth trauma
    • Head injury in adulthood
    • Alcohol abuse
    • Cerebral tumor
    • Cerebrovascular accident
    • Systemic lupus erythematosus
  • Psychological factors
    • These theories no longer hold credibility. Researchers now focus their studies of schizophrenia as a brain disorder.
    • Psychosocial theories probably developed early on out of a lack of information related to a biological connection.
  • Environmental Influence
    • Sociocultural factors: Poverty has been linked with the development of schizophrenia.
    • Downward drift hypothesis: Poor social conditions seen as consequence of, rather than a cause of, schizophrenia
    • Stressful life events may be associated with exacerbation of schizophrenic symptoms and increased rates of relapse.
    • Studies of genetic vulnerability for schizophrenia have linked certain genes to increased risk for psychosis and particularly for adolescents who use cannabinoids.
  • Theoretical integration
    • Schizophrenia is most likely a biologically based disease, the onset of which is influenced by factors in the internal or external environment.