Schizophrenia

Schizophrenia Etiology

• Causes of Schizophrenia:
  • No single known cause.
  • Research focuses on: Biological and Sociocultural factors.
    • Biological factors are the most promising explanation with the most research support.

Schizophrenia: Developmental Factors

• Early-onset schizophrenia (EOS):
  • Onset before 18 years old.
  • Characteristics:
    • Socially withdrawn.
    • Difficulty interacting with peers.
    • School adjustment problems.
  • Earlier onset often correlates with worse outcomes.
  • Adults with schizophrenia often displayed less sociability as children.

Biological Factors

• Genetic factors:

  • Diathesis-stress account:
    • Biological predisposition for schizophrenia.
    • The disorder is triggered by later exposure to stress.

• Genetics and family studies:

  • Twin studies suggest a heritability estimate as high as 79%, but at least nearly 50%.
  • Hundreds of genes (polygenic influence) in addition to epigenetic and environmental factors are likely to play a role.

• Genetic factors:

  • Biochemical abnormality theory:
    • Dopamine hypothesis: Increased dopamine levels.
    • Serotonin hypothesis: Decreased serotonin associated with negative symptoms.
  • Abnormal brain structure theory:
    • Larger ventricles in the brain.
    • Loss of gray matter.
  • Prenatal Viral Theory.

*New Targets for Schizophrenia Treatment Beyond the Dopamine Hypothesis
* Beyond Dopamine thearpy, there are other targets for schizophrenia that can be looked into.

• Cannabis use and schizophrenia: