PS280 Lecture 9: Week 9
Schizophrenia continued…
Multiple choice and short answer on midterm - no weekly quiz this sunday!
Etiology Continued…
Genetics
● Increased risk based on genetic relatedness
○ Identical twins - 44%
○ Fraternal twins - 12%
○ Children - 9%
● Adoption studies - missed the point on this check in text
● Most support for polygenic models
Dopamine Hypothesis
● Excess dopamine (D2 receptors) - receptors require more dopamine → increase
● Evidence
○ 1. Antagonists - neuroleptics (antipsychotic drugs) - reduce dopamine levels and
thus psychotic symptoms
○ 2. Negative side effects of neuroleptics are similar to Parkinson’s
■ L-Dopa
○ 3. Amphetamines - increase dopamine and has been evidence they could
increase psychotic symptoms
● However
○ Dopamine antagonists do not always work (if caused by excess dopamine should
always work)
○ Dopamine blocked right away but can take time for therapeutic effect
○ Dopamine antagonists work better on positive symptoms
Brain Structure
● Ventricle enlargement
● Prefrontal cortex: hypofrontality - suggests individuals with schizophrenia have less(?)
activity in their prefrontal cortex
Social Class
● Higher rates among lower class
● Sociogenic hypothesis: more stress → schizophrenia (eg financial problems)
● Social-selection hypothesis: schizophrenia → lower class (those who have it live in lower
classes because they can’t afford to live in other areas, and lower areas might = less
discrimination)
● Support for social selection: parents of patients with schizophrenia, children aren’t
necessarily from there but parents tend to move there
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Multiple choice and short answer on midterm - no weekly quiz this sunday! Adoption studies - missed the point on this check in text. Excess dopamine (d2 receptors) - receptors require more dopamine increase. Antagonists - neuroleptics (antipsychotic drugs) - reduce dopamine levels and thus psychotic symptoms. Negative side effects of neuroleptics are similar to parkinson"s. Amphetamines - increase dopamine and has been evidence they could increase psychotic symptoms. Dopamine antagonists do not always work (if caused by excess dopamine should always work) Dopamine blocked right away but can take time for therapeutic effect. Dopamine antagonists work better on positive symptoms. Prefrontal cortex: hypofrontality - suggests individuals with schizophrenia have less(?) activity in their prefrontal cortex. Sociogenic hypothesis: more stress schizophrenia (eg financial problems) Social-selection hypothesis: schizophrenia lower class (those who have it live in lower classes because they can"t afford to live in other areas, and lower areas might = less discrimination)
