Unit 3: Schizophrenia Flashcards
(57 cards)
What are the two major systems for the classification of mental disorders?
- World Health Organisation’s International Classification of Disease edition 10 (ICD-10)
- American Psychiatric Association’s Diagnostic and Statistical Manuel edition 5 (DSM-5)
How do the classifications differ from DSM-5 and ICD-10 ?
in DSM a positive system has to be present while in ICD two or more negative symptoms are sufficient
Positive symptoms of schizophrenia:
- hallucinations
- delusions
Negative symptoms of schizophrenia:
- avolition - finding it difficult to begin or keep up with a goal directed activity
- speech poverty
What is Co-morbidity ?
the occurrence of two illnesses or conditions together
What is symptom overlap ?
occurs when two or more conditions share symptoms
Evaluations of the diagnosis and classification of schizophrenia ?
- African Americans and English people of Afro-Carribean origin and several times more likely to be diagnosed - not because of genetic vunerability but cultural bias - some positive symptoms more accepted in African cultures - (Escobar 2012) pointed out white psychiatrists tend to over-interpret symptoms and distrust the honesty of black patients during diagnosis
- Longenecker et al ( 2010 )
men diagnosed more than women. genetic vunrability ? or gender bias ?
female patients typically function better (Cotten et al 2009) - explain why some women aren’t diagnosed due to the quality of interpersonal functioning making the case seem to mild to diagnose - Cheniaux et al
schiz is much more likely to be diagnosed under ICD. Suggests it is either over diagnosed with ICD or under using DSM - poor validity and weakness of diagnosis - Cheniaux (2009)
2 psychiatrists independently diagnose 100 patients - inter-rater reliability was poor - one diagnosing 26 with DSM and 44 with ICD, other diagnosing 13 with DSM and 24 with ICD - poor reliability
What are candidate genes ?
individual genes associated with risk of inheritance
What does polygenetic mean ?
requires a number of factors/ genes to work in combination
Study into candidate genes ?
Ripke et al (2004) genetic make up of 37,000 was compared to a 113,000 control group. 108 separate genetic variations were associated with an increased risk of schizophrenia
What is a gene associated with schizophrenia ?
those coding for the functioning of neurotransmitters like dopamine
The dopamine hypothesis - neurotransmitters :
dopamine is an important neurotransmitter in the functioning of several brain systems that may be implicated in the symptoms of S
What did the original dopamine hypothesis focus on ?
the possible role of high levels of dopamine in the subcortex
A word for high levels of dopamine ?
hyperdopaminergia
What have more recent versions of the dopamine hypothesis focused in?
abnormal dopamine systems in the brain’s cortex
What does low levels of dopamine in the prefrontal cortex result in ?
according to Rakic et al (2004) negative symptoms of schizophrenia
What does hypodopaminergia mean?
low levels of dopamine
What are neural correlates ?
patterns of structure or activity in the brain that occur in conjunction with an experience and may be implicated in the origins of that experience
Neural correlates of negative symptoms ?
Juckel et al (2006) measured activity levels in the ventral striatum in schizophrenic patients and found lower levels of activity than observed in the control group
- negative correlation between activity levels in the ventral striatum and the severity of overall negative symptoms
Neural correlates of positive symptoms ?
Allen et al (2007) scanned the brains of patients experiencing auditory hallucinations and compared them to a control group. Lower activation levels were found in the hallucinating group in the superior temporal gyrus and anterior cingulate gyrus - we can therefore say reduced activity in the superior temporal gyrus and anterior cingulate gyrus is a neural correlate of auditory hallucinations.
Evaluations of the biological explanations for schizophrenia :
- the correlation - causation problem
- the role of mutation
S can take place without family history of the disorder - one explanation of this is mutation caused by radiation, poisoning or a viral infection. Brown et al (2002) higher the paternal age the more likely schiz will be present - the role of the psychological environment is important but unclear
probability of developing S from a identical twin is less than 50% so there must be other factors
What is the schizophrenogenic mother ?
Fromm-Reichmann’s (1948) psychodynamic explanation for schizophrenia based on accounts she heard from patients about their childhoods - most talked about a specific type of parent ‘schizophrenogenic mother’ who according to Fromm is cold, rejecting and controlling, and tends to create a family climate characterised by tension/secrecy - leading to distrust, delusions and ultimately schizophrenia
What is the double-bind theory ?
Bateson et al (1972) argued family environment is important in the development of S emphasising the role of communication style. Child regularly finds themselves fearing their doing something wrong but receiving mixed messages. When they ‘get it wrong’ the child is punished with withdrawal of love. leaving them with a warped understanding of the world reflected in symptoms such as paranoid delusions and disorganised thinking
What are the elements of expressed emotion :
- verbal criticism
- hostility
- emotional over involvement
