Neural Correlates Flashcards
What are neural correlates?
Neural correlates are measurements of the structure or function of the brain that occur in conjunction with an experience - in this case, to see if they correlate with the symptoms of schizophrenia. Both positive and negative symptoms have neural correlates.
Where is the neural correlates for negative symptoms?
Abnormalities in the ventral striatum.
Where abouts in the brain is the ventral striatum located?
In the central regions of the brain.
What are the central regions of the brain (e.g. Ventral striatum) believe to be involved in?
They are believed to be involved in motivation (the anticipation of reward)
What happens if there is an abnormality in the ventral striatum?
It may lead to avolition (negative symptoms)
Describe the study that researched ventral striatum
Juckel et al measured brain activity in the ventral striatum in schizophrenics and found lower levels of activity in this area of the brain than in controls. This is a negative correlations as low levels of activity in this part of the brain are associated with increased negative symptoms (avolition).
Thus activity in the ventral striatum is a neural correlate of negative symptoms of schizophrenia.
Where is the neural correlates of positive symptoms?
- superior temporal gyrus
* anterior cingulate gyrus
Describe the study of superior temporal gyrus and anterior cingulate gyrus
Allen et al scanned the brains of patients experiencing auditory hallucinations whilst they identified whether they though pre-recorded speech was their own or others. They were compared to a control group of non-schizophrenics on the same task.
They found lower activation levels in the superior temporal gyrus and anterior cingulate gyrus in the hallucination group than in the control group.
This reduced activity in these two areas of the brain is a neural correlate of auditory hallucinations.
Does abnormalities in superior temporal gyrus or anterior cingulate gyrus correlate with positive or negative symptoms of schizophrenia?
Positive symptoms such as hallucinations
Is the correlation between superior temporal gyrus/anterior cingulate gyrus a positive or negative correlation?
It is a negative correlation because low levels of activity in these parts of the brain are associated with increased positive symptoms (hallucinations).
EVALUATION
Give a limitation of neural correlates to do with the correlation-causation problem
A limitation of neural correlates is that it creates a correlation-causation problem.
There are number of neural correlates for both positive and negative symptoms of schizophrenia. Although this type of research is useful in flagging up certain parts of the brain that are not working normally, this kind of research leaves some important questions unanswered.
Does the damage to the striatum cause negative symptoms, or does having negative symptoms result in less information passing through the striatum, resulting in reduced activity?
This cause and effect issue means that existence of neural correlates tells us little in itself about what causes schizophrenia.
EVALUATION
Describe a limitation of neural correlates in relationships bf to the role of environment
When assessing the role that brain abnormalities play in the development of schizophrenia, consideration must also be given to environmental factors, such as substance abuse and stress levels, which may also be having a damaging effect on the brain tissue.
This means that there are external factors other than neural correlates that need to be taken into consideration when considering the role that brain damage plays in the development of schizophrenia.
EVALUATION
Describe a strength of neural correlates in relation to drug treatment
A strength of neural correlates is that they could explain why some patients do not respond to drug treatment.
It may be that schizophrenia patients who do not respond to medication do not do so because structural damage does not allow antipsychotic medications to have a therapeutic effect in reducing symptom levels.
(Reduced activity in parts of the brain mean the drugs might not work)
