Biological Explanation- Structural Abnormalities Flashcards
What are the four lobes of the brain?
Partictal lobes
Occipitual lobe
Temporal lobe
Frontal lobe
What is the ceribelum responsible for?
It is responsible for motor controls
What does the brain stem do?
It regulates automatic processes
What is the cerebral cortex?
The main part of the brain
What are the ventricles responsible for?
Maintaining the pressure in the brain
What are the 3 structural abnormalities which are linked with Schizophrenia?
Englarged ventricals
Cortical atrophy
Reversed cerebal asymmetry
What would enlarged ventricals be a sign of?
It shows that Gray matter has been lost, as a result ventricles have swelled and filled with Cerebalspinal fluid to match preasure of the brain
What has been found about a Schizophrenic persons ventricles compared to a normal brain?
Schizophrenic individuals appear to have larger ventricicals
Evidence : Weinberger et al (1979) used CAT scans and found that 40 % of his 58 Schizophrenic participants had significantly larger venctricals compared to his 56 control paticipants , 53% with Chronic Schizophrenia exceeded two S.D of the control
What is Cortical Atrophy?
The loss of neurons in the cerebel cortex
Which are the two ways cortical atrophy can take place?
All over the brain (making it look like the brains shrunk) OR it can be focused in a limited area
What percentage of people with chronic Schizophrenia display Atrophy?
Vita et al (1988) claims that 33% suffer from cortical atrophy and also ventricle enlargement
What is the typical symtery of a brain?
The left hemisphere of the brain is slightly larger than the right (cerbal aysmmetry)
What is the typical asymmetry of a Schizophrenic person?
Their right hemisphere is slightly larger than the left (reversed cerebral asymmerty)
What can damage of the left hemisphere lead to?
As the left is typically linked to speech , damage could lead to alogia (poverty of speech)
What did Lunchins et al (1979) find using CAT scans about the link between atrophy and reversed cerebal asymmetry?
He found that only those without other forms of atrophy displayed ‘reversed’ brains
What are four evaluation points of Structural abnormalities to biologically explain Schizophrenia?
Replicability of findings
Effect of Antipsychotics
Structural abnormalities aren’t linked to Schizophrenia alone
Neurodegenerative or Neurodevelopment?
What is the evaluation point of the effect of Antipsychotics on brain structure?
The drugs used to treat Schizophrenia are very powerful and can significantly impact brain tissue
Evidence - Lyon et al (1981) found a negative correlation between an increase of medication and a decrease in density of patients brain tissue
Explain the evaulation point of structural abnormalities not only being linked to Schizophrenia?
Structural abnormalities such as enlarged venctricals are also present in a number of other disorders , so cannot help us discern exactly what the patient is suffering from without further evaluation
Evidence: Roy et al (1998) claimed that Victims of Bipolar disorder and Schizoaffective disorder also display the same structural abnormalties
Why is the evaluation point of the findings being replicable a strength?
It is a stregnth as abronzmlties can be relaibly and effectively tested for due to the research being scientific as it uses brain scans , meaning that scans can be used to highlight SCZ
Evidence: Mcarley and collegues (1999) claimed that the presence of englarged ventricals in Schizophrenic brains is the most reliable finding in research that uses brain scans
Why is the evaulation point of Neurodegenerative or neurodevelopmental a weakness?
The cause for Schizophrenia is still unknown as , whilst structural abromalties are clearly shown to correlate with SCZ , we don’t know if they are a cause or a consequence of Schizophrenia. Meaning the explination is incomplete
