Schizophrenia - Biological Explanations Flashcards
Diathesis stress model researcher?
Gottesman and Reilley
Gottesman and Reilley?
Many people have a biological predisposition for SZ which is triggered by psychological stressors
Biological explanations for SZ?
Genetic factors and the dopamine hypothesis
Genetic factors are looked at in…
family studies, twin studies and adoption studies
Family study on SZ?
Gottesman
Gottesman?
46% chance if both parents had SZ, 13% if one parent, 9% if a sibling had it and 1% chance for general population (40 european studies)
Kety et al? (f)
20+ year study diagnosed SZ in 16.2% of the high risk group (mothers with SZ) and 1.9% of the low risk group, even when matched
Twin study on SZ?
Gottesman and Shields
Gottesman and Shields?
42% concordance rate for hospitalisation and diagnosis for MZ twins, 9% for DZ twins (57 twin pairs)
Adoption study on SZ?
Kety et al
Kety et al? (a)
High rates of diagnosis for chronic SZ in adoptees whose parents had the same diagnosis, despite being adopted by ‘healthy’ parents
Weaknesses of genetic factors in SZ?
Methodological problems
Reductionist
Ignores nurture
Strengths of genetic factors in SZ?
Support
Supporting evidence for genetic factors in SZ?
Kety et al
Methodological problems in genetic factors in SZ?
Most studies have broadened definition of SZ to include non-psychotic ‘SZ spectrum disorders’
Research on SZ spectrum disorders?
Kety et al found no full cases of SZ among 1st degree relatives of children with SZ spectrum disorders
Reductionism in genetic factors in SZ?
May be more to do with common rearing patterns or other factors such as EE