Schizophrenia: Biological Explanations Flashcards
(12 cards)
what’s the idea of SZ running in the family?
there’s systematic investigations of the extent to which greater genetic similarity between family members with the likelihood of developing SZ. there’s a strong relationships between the degree of genetic similarity and shared risk of SZ. it’s weak evidence as families often share the same environment.
what’s candidate genes of SZ?
SZ is polygenic as it requires a number of factors to work in combination. it’s also aetiologically heterogeneous as different combinations lead to the condition.
what was Ripke’s research into candidate genes for SZ?
Ripke looked at genome-wide studies. the genetic makeup of 37,000 patients compared with 113,000 control. 108 seperate gene variations associated with risk of SZ.
what’s the dopamine hypothesis for SZ?
neurotransmitters work differently in SZ patients. dopamine is involved and important in the fucntioning of several brain systems that are implicated in SZ symptoms.
what’s the hyperdopaminergia in the subcortex?
the original version of dopamine hypothesis focused on role of high levels of dopamine in the subcortex. an excess of dopamine receptors in Broca’s area may be associated with speech poverty and auditory hallucinations.
what’s neural correlates?
meaurements of the structure or function of the brain that correlates with an experience.
what’s neural correlates of negative symptoms?
avolition involves loss of motivation (anticipation of a reward). the ventral striatum is involved with anticipation. abnormality to this area may result in avolition. Juckel
what’s hypodopaminergia in the cortex?
more recent version, focuses on abnormal dopamine systems in the cortex. Goldman-Rakic identified a role of low levels of dopamine in the prefrontal cortex in negative symptoms.
what are neural correlates of positive symptoms?
Allen scanned the brains of patients experiencing auditory hallucinations and compared them to a control group whilst they identified pre-recorded speech as theirs or others. lower activation levels in the superior temporal gyrus and anterior cingulate gyrus were found in the hallucination group, who made more errors.
what are the multiple sources of evidence for genetic susceptibility? (A03)
The Gottesman study shows how genetic similarity and shared risk of SZ are closely related. adoption studies show children of SZ sufferers still had a heightened risk of SZ. there is an overwhelming evidence that genetic factors make people more vulnerable to develop SZ.
what’s mixed evidence for the dopamine hypothesis? (A03)
