Neural Correlates (biological) Flashcards
What is the dopamine hypothesis?
- sz patients have more dopamine receptors
- higher dopamine levels
- drugs (phenothiazine) block dopamine activity by binding to receptors
- positive symptoms decrease
What facts/tests have been conducted to support the dopamine hypothesis?
- L-Dopa drug was tested on healthy non-psychotic people - drug induces symptoms bc of increased dopamine levels
- post mortem studies - sz patients have inc. dopamine (receptors) in left amygdala of the brain
- PET scans show abnormal dopamine metabolism in sz patients
- hypothesis linked to fault in genes causing inc. in dopamine levels
Evaluate the dopamine hypothesis.
(+) research support - Davidson gave sz patients L-dopa and symptoms worsened
(+) brain scans provide evidence and support - more reliable and valid
(-) cause and effect
(-) reductionist
(-) dopamine associated with other illnesses - mania wasn’t cured with phenothiazine
What study did Swayze conduct?
- neural correlates
- 50 sz studies, examined their brain imaging via MRI scans
- looked at brain structure
What did Swayze’s study find?
- decrease brain weight
- enlarged ventricles (filled with water)
- smaller hypothalamus
- less grey matter
- structural abnormalities in pre frontal cortex
Evaluate Swayze’s study.
(+) supporting evidence that problems in brain functioning/structure contribute to sz
(+)/(-) supporting psychological evidence that sz caused by neural correlates changing in the brain during pre natal development in the womb. Doesnt explain sz developing in early adulthood. Weinberger states pre frontal cortex develops during adolescence - damage only noticable then.
(-) Andreason - ventricle enlargement isn’t significant. Little difference in neural correlates between sz and healthy people.
(-) cause and effect
(-) Davidson and Neale - enlarged ventricles also in manic patients. Enlarged ventricles can’t cause sz alone (vulnerability factor).
