biological explanation: neural correlates Flashcards
what are the parts of the neural explanation?
- dopamine hypothesis
- brain structures
what is the dopamine hypothesis?
- dopamine is linked to onset of SZ - high or low
hyperdopaminergia
high levels of dopamine
what happens if there is high levels of dopamine released in synapse>
hyperdopaminergia
what symptoms are linked to hyperdopaminergia?
- hallucinations
- excess in sub-cortex in Broca’s area= poverty of speech, auditory hallucinations
what supporting research is there for hyperdopaminergia?
Iverson
- post- mortems on people who had SZ and found they had excessive dopamine in limbic system
- high levels linked to SZ
counter of Iverson?
- no cause and effect
- temporal + spaitial resolution?- dead
hypodopaminergia
low levels of dopamine
symptoms linked to hypodopaminergia?
negative symtpoms like avolition because occurs in pre-frontal cortex which is responsible for thinking
what is the conclusion for dopamine?
- both are correct and involved with SZ
- hard to treat bc dont know which it is
3 brain structures linked to SZ?
- ventricles
- superior temporal gyrus
- ventral striatum
how do ventricles link to SZ?
- using brain scans found SZ twins had enlarged ventricles compared to control group suggesting there is a link
short evaluation of ventricles
good- accurate, clear, scientific as brain scans
bad- just correlational, which caused which?
how does the superior temporal gyrus link to SZ?
- Allen et al, fMRI
- low levels of activity in this area experienced auditory hallucinations compared to control group
how does the ventral striatum link to SZ?
- located in subcortex which is involved in motivation and anticipation of reward
- links to avolition
supporting research for ventral striatum?
Juckel et al-> negative correlation of activity levels in ventral straitum and severity of negative symptoms
how is the explantion objective?
- great deal of empirical evidence
- ventricles, fMRI for superior temproal gyrus
- brain scans
- no bias
- spatial resolution
what is a problem with the data being correlational?
- no cause and effect
- dopamine= SZ or SZ= dopamine change
- do these abnormalities cause SZ or does SZ cause them?
- cant rule out env factors that may lead to brain abnormalities like substance abuse
- nurture
what practical application is there?
- antipsychotic drugs
- binds to dopamine receptors (hyper) and reduces symptoms
- counter-> low or high= if unsure of cause cant give effective treatment + severe side effects, only hyper
nature nurture debate
- nurture not considered
- better to take interactionist approach (hollistic) such as diathesis stress model (have vunerability and trigger)
holism reductionism debate
biologically reductionist
- reduce SZ down to dopamine levels too high or low and brain structures
