Schizophrenia- TB Flashcards
What is schizophrenia?
A severe mental disorder involving impaired insight and loss of contact with reality
What are classifications of mental disorders?
Used when diagnosing disorders
What are the two classifications and where are they used?
1) DSM- USA
2) ICD- Europe
What is the difference between ICD & DSM?
ICD classification= 2 negative symptoms to diagnose
DSM classification= 1 positive symptom to diagnose
What are positive symptoms?
Symptoms that appear to reflect an excess or distortion of normal functions
What are negative symptoms?
Symptoms that appear to reflect a reduction or loss of normal functions- often persist in periods of low/no positive symptoms
What are the 2 main positive symptoms of schizophrenia?
1) Hallucinations
2) Delusions
Which symptom are hallucinations and what are they?
Positive- Bizarre, unreal perceptions of the environment (mainly auditory, can be visual or olfactory too)
Which symptoms are delusions and what are they?
Positive- Bizarre beliefs that seem real to the diagnosed individual but aren’t real e.g. being followed, inflated beliefs of importance etc.
What are 2 other examples of positive symptoms?
1) Disorganised speech- can’t organise thoughts
2) Disorganised/catatonic behaviour- inability to initiate/motivate a task
What are the 2 main negative symptoms of Schizophrenia?
1) Speech poverty (alogia)
2) Avolition
Which type of symptom is speech poverty and what is it?
Negative- Decrease in speech fluency & productivity reflecting slowing or blocked thoughts
Which type of symptom is avolation and what is it?
Negative- Loss of interests & desires, inability to initiate & persist with goal directed behaviour
What are 2 other examples of negative symptoms and what are they?
1) Affective flattening- decrease in range & intensity of emotional expression
2) Anhedonia- loss of interest or pleasure in all/almost all activities, lack of reactivity to normally pleasurable stimuli
What is co-morbidity?
The extent that 2 or more conditions can occur, common among patients with schizophrenia ( e.g. anxiety, depression etc)
Why is co-morbidity a limitation of diagnosis of schizophrenia (validity eval)?
Can be a problem as it means schizophrenia may not exist as a distinct condition (people diagnosed with schizophrenia may have other conditions instead)
Explain gender bias in diagnosis as a limitation of diagnosing schizophrenia (validity eval.)
Men are diagnosed more than women- possibly as men are more vulnerable due to genetic factors, or that women are underdiagnosed due to closer relationships & therefore more support=better functioning
What can gender bias in diagnosis of schizophrenia lead to?
Women may not receive beneficial treatment
When is gender bias in diagnosis less evident?
With female psychiatrists (Loring & Powell 1988)
Explain cultural bias as a limitation of schizophrenia diagnosis (validity eval)
Some symptoms of schizophrenia have different meanings in different cultures e.g. hearing voices is attributed to communication with ancestors in afro-Caribbean countries, but schizophrenia in UK= 10x more likely to be diagnosed as discrimination by a culturally biased diagnostic system
Explain symptom overlap as a limitation of schizophrenia diagnosis (validity eval)
Considerable overlap between symptoms of schizophrenia & symptoms of other conditions e.g. bipolar- delusions, hallucinations & avolition
Why does symptom overlap affect to do with diagnosis?
Schizophrenia is hard to distinguish compared to bipolar
Why does symptom overlap affect to do with classification?
Could be that bipolar & schizophrenia are variations of one condition
What are 2 limitations that have similar results?
Co-morbidity & symptom overlap- schizophrenia may not exist as a distinct condition & even when it does it is hard to distinguish
What are the two biological explanations of schizophrenia?
1) Genetics
2) Neural correlates
What are 3 sub-factors of genetics (inherited factors) as a biological explanation of schizophrenia?
1) Family studies
2) Candidate genes
3) Mutation
What are 4 limitations (eval points) for diagnosis and classification of schizophrenia?
1) Co-morbidity
2) Gender bias in diagnosis
3) Cultural bias
4) Symptom overlap
Explain Gottesman’s research on family studies as a part of the genetic biological explanation for schizophrenia
Conducted a large scale study, finding that if you have a:
Aunty with schiz.=2% chance you develop schiz.
Sibling with schiz.=9%
Identical twin=48%
What are candidate genes?
Genes that are related to a particular trait
What is schizophrenia considered to be to do with candidate genes?
Polygenic= A characteristic that is influenced by two or more genes
Explain Ripke et al’s (2014) research into candidate genes as a part of the genetic biological explanations for schizophrenia
Compared genetic make up of 37000 people with schizophrenia to 113000 people without schizophrenia (control group). Ripke found 108 separate genetic variations that can leas to the disorder
Explain mutation as a part of the genetic biological explanation of schizophrenia
Can develop individuals who have no family history of the disorder possibly due to gene mutation in DNA of parent (due to radiation or infection)
What research supports mutation as part of the genetic biological explanation?
Positive correlation found with parental age & schizophrenia
0.7% with fathers <25
2% with fathers >50 (Brown et al 2002) due to increased risk of sperm infection
What are neural correlates?
A biological explanation of schizophrenia, suggesting a brain structure/function is associated with Sz
What are 2 hypotheses of neural correlates as part of the biological explanation of schizophrenia?
1) Dopamine hypothesis
2) Revised hypothesis
What is the dopamine hypothesis?
Theory suggested after antipsychotics used to treat Sz were found to cause symptoms to Parkinson’s, and vice-versa for Parkinson’s patients. Therefore was suggested schizophrenia was caused by high levels of DA that were in ‘L-Dopa’ drug given to Parkinson’s sufferers
What does DA stand for?
Dopamine
Why do high levels of DA cause schizophrenia according to the dopamine hypothesis?
It causes more neurons to be fired, causing hallucinations & delusions
What is the revised hypothesis?
Updated version of the dopamine hypothesis to include hypodopaminergia
What does the revised hypothesis suggest?
Low DA levels in the prefrontal cortex cause negative symptom of cognitive problems
Suggested that both high DA and low DA in different areas of the brain cause schizophrenia
What is hyperdopaminergia?
Excess of DA (high DA)- causes positive symptoms
What is hypodopaminergia?
Shortage of DA (low DA)- causes negative symptoms
What is an example of a neural correlate of negative symptoms?
Avolition associated with abnormality of the ventral striatum of the brain
What is an example of a neural correlate of positive symptoms?
Hallucinations associated with low activation levels in the superior temporal gyrus
What are the 2 parts of psychological explanations for schizophrenia?
1) Family dysfunction
2) Cognitive explanations
What are 3 parts of family dysfunction as a psychological explanation for schizophrenia?
1) Double bind theory
2) Expressed emotion (EE)
3) Schizophrenogenic mother
What is double bind theory a part of?
Family dysfunction- psychological explanation for sz
What is double bind theory?
Bateson (1956)- Contradictory messages reduce a child’s ability to respond as one message invalidates another.
This prevents development of an internal coherent construction of reality, which leads to Sz symptoms
What is expressed emotion a part of?
Family dysfunction- psychological explanation for sz
What is expressed emotion?
A negative emotional environment- high EE+ environment full of criticism & hostility (talk more & listen less)
Low EE families can reduce relapse in patients
What affect does a high EE family have?
Patient 4x more likely to relapse- causes stress beyond patients coping ability
What affect does a low EE family have?
Can reduce relapse in patients
What is schizophrenogenic mother a part of?
Family dysfunction- psychological explanation of sz
What is schizophrenogenic mother and what is it based on?
Psychodynamic explanation- based on accounts patients made of their mothers
Who suggested a schizophrenogenic mother?
Fromm-Reichmann (1948)
What are the characteristics of a schizophrenogenic mother?
Cold, rejecting & controlling
What impact does a schizophrenogenic mother have?
Creates a family dispute characterised by tension & secrecy- leads to distrust, then develops paranoid delusions and eventually schizophrenia
What does schizophrenogenic mean?
Schizophrenia causing
What are the 3 parts of cognitive explanations of schizophrenia as a part of psychological explanation for sz?(2&3 subsections of 1)
1) Dysfunctional thought processes
2) Metarepresentation dysfunction
3) Central control dysfunction
Who identified metarepresentation dysfunction & central control dysfunction as part of the cognitive explanation?
Frith (1992)
What is metarepresentation dysfunction a part of?
Cognitive explanation- Psychological explanation for sz
What is metarepresentation?
Cognitive ability to reflect our own thoughts & behaviour, allowing self-insight to goals & intentions, & also interpret behaviour of others
What does metarepresentation dysfunction cause?
Impairs ability to recognise our own actions & thoughts as belonging to ourselves- explaining hallucinations & delusions as being thought insertion
What is central control dysfunction a part of?
Cognitive explanation- psychological explanation of sz
What does central control dysfunction do?
Problems with ability to suppress automatic responses when carrying out deliberate actions
What does central control dysfunction cause?
Speech poverty & thought disorder- thought derailment= every word triggers an association & an auto response that cannot be supressed
What is dysfunctional thought processes as a part of the cognitive explanation of psychological explanations of sz?
General overview- focuses on role of mental processes e.g. reduced thought processing in ventral striatum=negative symptoms
What are 4 evaluation points for family dysfunction as a psychological explanation for schizophrenia?
1) Tienari et al- adopted children study
2) Poor evidence base for explanations
3) Research is highly socially sensitive
4) Distal explanations
Explain Tienari et al (1994) research as evaluation for family dysfunction
Found adopted children with schizophrenic biological parents ↑ chance to have sz, however difference emerged only in situations where adopted family was “disturbed”- suggests illness manifests itself under appropriate environmental conditions , THEREFORE, genetic vulnerability alone is not sufficient
Is Tienari’s research support or criticism of family dysfunction as a psychological explanation for sz?
Strength, criticises biological explanations
Explain poor evidence for explanations as evaluation for family dysfunction as a psychological explanation for sz
No evidence to support the importance of traditional family based theories (schizophrenogenic mother & double bind) which are based on clinical observations of patients & assessment of their mothers THERFORE family explanations haven’t been able to account for the link between childhood trauma & schizophrenia
Is poor evidence base for explanations support or criticism of family dysfunction as a psychological explanation for sz?
Criticism
Explain research being highly socially sensitive as evaluation for family dysfunction as a psychological explanation
Research should be stopped, leads to parent-blaming, which is hard if they are already dealing with a child with schizophrenia
What are 3 evaluation points of cognitive explanations?
1) Stroop test evidence
2) Proximal origins of symptoms
3) Partial explanations
Explain stroop test evidence as evaluation of cognitive explanations as a psychological explanation for sz
Supports Frith’s central control theory as people with sz took twice as long to say the font colour, as suggested by cct.
THEREFORE their cognitive processes of people with sz are impaired
Explain proximal origins of symptoms as evaluation of cognitive explanations as a psychological explanation for sz
Proximal origins= what is happening NOW to produce symptoms= a limitation as cog. explanations only explain proximal origins of symptoms
Explain distal explanations as an evaluation of family dysfunction as a psychological explanation of sz
Distal explanation= Focus on what initially caused the condition
Explain providing partial explanations as evaluation for cognitive explanations as a psychological explanation of sz
Limitation- Unclear & not well-addressed how genetic variation or childhood trauma might lead to problems with meta-representation or central control
What are 2 types of drug therapy for sz?
1) Typical antipsychotics
2) Atypical antipsychotics
What are typical antipsychotics?
DA antagonists- block DA receptors in synapses in the brain
What is an example of typical antipsychotics?
Chlorpromazine- relieves + symptoms (tablet), negative effect= extrapyramidal effect
What is an extrapyramidal effect to do with?
Movement/motor control of body
How do atypical antipsychotics work?
Act on D2 receptors (like typical) but only temporarily- then rapidly dissociate allowing normal DA transmission
What 3 ways are atypical antipsychotics different from typical antipsychotics?
1) Lower risk of extrapyramidal side effects
2) Beneficial effects on - symptoms & cog. impairment
3) Suitable for treatment-resistant patients
What are 2 examples of atypical antipsychotics?
1) Clozapine
2) Risperidone
What is a strength of drug therapy for sz?
Ben THornley- reviewed studies comparing chlorapromazine to placebo drug- 1121 participant showed drug was more effective at decreasing symptoms
What are 2 limitations of drug therapy for sz?
1) Antipsychotics used to calm sufferers down to be worked on rather than to benefit patients BUT this can help them
2) Negative side effects:
ST= dizzy, sleepy, agitated, weight gain etc
LT= Tardive dyskinesia= sensitive DA= involuntary facial movements
& Neuroleptic maligant syndrome (NMS) =drug blocks DA action in hypothalamus
BUT atypical drugs reduce these effects
