Schizophrenia Flashcards
what is schizophrenia? (SZ)
a severe mental disorder where contact with reality and insight is impaired
it is a type of psychosis
what are positive symptoms of SZ
atypical symptoms experienced in addition to ordinary functioning
1. hallucinations
sensory experiences that have no basis in reality OR are distorted perceptions of your surroundings (e.g., the person in front of you has green teeth)
- delusions
beliefs that have no basis in reality
delusions of grandeur- thinking that you are someone important e.g., PM
paranoid delusions- thinking you are the victim of a conspiracy
what are negative symptoms of SZ?
atypical symptoms that represent a loss of usual experience
1. speech poverty/disorganisation
reduced frequency/quality of speech e.g., jumping from topic to topic or mixing up the order of your words
2. avolition
loss of motivation to carry out tasks which results in lowered activity levels e.g., not washing
how is SZ classified?
DSM V - requires one positive symptom
ICD - requires 2 negative symptoms
define co morbidity and symptom overlap
- co-morbidity
when two disorders are often diagnosed together (e.g., depression and anxiety). This causes us to question the validity of classifying and diagnosing them separately as they may be part of the same disorder - symptom overlap
when similar symptoms are seem in multiple conditions (e.g., avolition can be seen in SZ and depression). calls into question the validity and accuracy of our classifications
why is reliability and validity of classification and diagnosis so important
issues with the classification of SZ could lead to inaccurate diagnosis- people who need treatment may not get access to it and vice versa.
evaluate the classification and diagnosis of SZ
-: CHENIAUX (2009) FOUND LOW INTER RATER RELIABILITY
. 2 psychiatrists had to independently diagnose 100 ppts for SZ using both DSM and ICD classification
. inter-rater reliability was low: under DSM classification one psychiatrist diagnosed 13, and one diagnosed 26.
. for IDC, one diagnosed 22 and the other did 44
. suggests that for both classification systems, the diagnosis was inconsistent- this means that classification may not be fully operationalised, making diagnoses more subjective.
+: CLASSIFICATION UNDER DSM HAS IMPROVED
DSM has since changed its classification of SZ. in 2019 Osario tested the updated classification for reliability of diagnosis for 180 individuals. pairs of psychiatrists received an inter-rater reliability of +0.97, which is extremely high contrasting the negative results of the 2009 study. suggests that DSM has updated their classification to be more objective.
-: SYMPTOM OVERLAP
symptoms of SZ are also found in other disorders- e.g., delusion and avolition can be symptoms of bipolar disorder.
this calls into question the validity and accuracy of SZ classification, and increases the risk of psychiatrists mixing up SZ and BPD diagnoses
-: SYMPTOM OVERLAP HAS NEGATIVE IMPLICATIONS
under the IDC classifications, a patient could receive diagnosis for SZ, but many of the same patients would receive a BPD diagnosis under DSM.
Ketter highlights that misdiagnosis of condition can lead to a delay in receiving relevant treatment (like anti-psychotic drugs), which could lead to further degeneration of condition, and higher chances of suicide.
T= SYMPTOM OVERLAP REDUCED INTERNAL VALIDITY AND HAS -IVE IMPLICATION FOR PATIENTS.
-: GENDER BIAS IN DIAGNOSIS
. study: randomly selected 290 male and female psychiatrists, gave them 2 case studies and asked them to give a diagnosis. if patient was described as male or no gender, 56% of psychiatrists gave a SZ diagnosis, but if the same case was described as female, only 20% of psychiatrist gave diagnosis (this gender bias was not evident in female psychiatrists)
shows that diagnosis of SZ can be skewed by gender of individual and diagnose, reducing its objectivity.
-: CULTURAL BIAS IN DIAGNOSIS
British people of African-Carribean descent are 9x more likely to receive a SZ diagnosis than white British. higher statistic was not present in people living in African Carribean countries.
suggests and over interpretation of symptoms in black British people, reducing reliability and objectivity
T = BIASES CAN SKEW DIAGNOSIS.
what is the genetic explanation for SZ (biological explanations AO1)
people can inherit variants of genes that make them vulnerable to developing SZ- AKA candidate genes.
Kendler found that first degree relatives of those with SZ were 18x more likely to develop SZ than average, suggesting that chances of developing SZ increases in line with genetic similarity.
what is the mutation explanation for SZ (biological explanation AO1)
- mutations in parental DNA caused by eg., radiation, poison, viral infection…
- study of parents without SZ, who then had children with SZ
there was a correlation between paternal age (increased age associated with greater risk of sperm mutation) and risk of SZ, increasing from a 0.7% chance in father’s under 25 to a 2% chance in people with fathers over 50.
describe dopamine hypothesis
original dopamine hypothesis - HYPERDOPAMINERGIA
high levels of dopamine in subcortical areas of the brain could cause SZ, e.g., excess of DA receptors in pathways from sub cortex to Broca’s area could cause speech poverty.
HYPODOPAMINERGIA - lack of dopamine in prefrontal cortex can lead to cognitive problems.
evaluate the biological explanation for SZ
+ GENETIC EXPLANATION SUPPORTED BY SCIENTIFIC RESEARCH
e.g., Gottesman found that there was a 17% concordance of SZ in DZ twins compared to 48% concordance in MZ twins. this suggests largely genetic cause
. quantitative data means it can be statistically analysed for significance, making conclusions even more objective
. increased internal validity makes entire explanation more valid.
-: PARTIAL EXPLANATION
strong, empirical method does not change the findings of research
if SZ was 100% heritable, concordance rates of SZ in MZ twins would be 100%
according to the Tienari study- out of 14 adoptees who developed SZ 3 of them had no genetic risk.
. this suggests that other explanations like psychological ones must be considered, such a trauma- Morkved found that 67% of SZ patients suffered at least one trauma.
T = despite supporting research, the biological explanation is not a holistic explanation of SZ
-: SZ IS POLYGENIC
multiple genes involved in SZ. Ripke analysed genomes of 37,000 SZ patients and found 108 genes involved in SZ- AETIOLOGICALLY HETEROGENOUS
if we follow candidate genes, we are unlikely to find a universal treatment, limiting its practical value.
-: GENETIC COUNSELLING
. although it may not lead to a treatment research into the influence of genetics on SZ has formed genetic counselling, where people (who may have a close relative with SZ) are able to get a risk estimate that their child will develop SZ
. although this is just an estimate and does not guarantee that their child will not develop SZ, it is still practical to be aware.
PRACTICAL APPLICATION OF DOPAMINE HYPOTHESIS
. has led to drug therapy treatment, like antipsychotics, which act as dopamine antagonists, and reduce its levels in the brain. this is shown to be a highly effective treatment for alleviating SZ symptoms, e.g., Kane (2019) found that only 30% of SZ cases didn’t response to APs
. the way APs work on/correct dopamine systems suggests a biological cause for SZ
-: TREATMENT CAUSATION FALLACY.
. just because there is evidence for an effective biological treatment, this doesn’t necessarily support the dopamine hypothesis
the drug therapy could be effective for different reasons
Moghaddam and Javitt criticise the biological explanation for over-emphasising dopamine systems and suggest glutamate and serotonin NTs also play a key role. Clozapine works on both of these NTs and Meltzer found it was the most effective AP, suggesting the influence of DT on these NTs are more important
. so, we cannot conclude the validity of the biological explanation from its practical value
describe family dysfunction explanation of SZ (psychological explanation of SZ)
- poor family dynamics and interactions can lead to SZ
- FROMM-REICHMANN- SCHIZOPHRENOGENIC MOTHER
. if a mother is cold, rejecting and controlling, a family climate of tension and secrecy is created. this leads to distrust and later, paranoid delusions. - BATESON- DOUBLE BIND THEORY
SZ may be caused by poor communication such as mixed messages
. this is where parent may express care while being critical (you look nice for once)
this behaviour leads to a contradiction in the child’s verbal and non verbal behaviour
.child may be punished by withdrawal of love which makes them understand the world as dangerous, which is reflected in symptoms like delusions and speech disorganisation
.poor communication could also be linked to symptoms like social withdrawal, or flattening of affect
. this is a factor in developing SZ, not the underlying cause - EXPRESSED EMOTION
. interactionist- diathesis stress model
high levels of (mostly negative) emotion expressed towards SZ such as
- verbal criticism or violent abuse
- hostility, anger or rejection
- emotional over-involvement of person, including needless self sacrifice.
. primary explanation of relapse
evaluate family dysfunction explanation
-:PSYCHIC DETERMINISM
. behaviour completely controlled by upbringing
. negative effect on the mindset of SZ, they are less likely to engage in condition as they think it is out of their control. reduced engagement in treatments like CBT.
-:SOCIALLY SENSITIVE
could lead to parent blaming, specifically mother due to SGM explanation the highlights the role of mothers. the mother may be judged and outcasted from society leading to increased guilt
t = negative implications for individual’s health, as well as their family.
+: RESEARCH SUPPORT
Morkved found 67% of SZ patients reported having at least one childhood trauma, mostly abuse. external validity
-: PARTIAL EXPLANATION
family dysfunction is broad and it does not explain why not all people with controlling mothers or poor family communication get SZ.
Bateson clarified that double bind theory should not be considered the underlying universal cause of SZ, just a risk factor.
little point in forming treatments from this explanation, as it does not actually address identifying cause of SZ. by addressing underlying cause, we could prevent SZ in all
+: Linzen et al; SZ patients who returned to family’s who showed EE were 4x more likely to relapse
. + practical application
describe the cognitive explanation for SZ
- CONSCIOUS AND PRE-CONSCIOUS THINKING
conscious processing- we are aware of these feelings and actions. this has a limited capacity
preconscious processing- automatic processes taking place without our awareness, such as heart beating.
.in non SZ, we can filter out irrelevant stimuli so only important stimuli is in conscious processing
. in SZ they cannot filter so irrelevant information goes into conscious processing, but our mind assumes that anything in conscious processing is important, so SZ people will give meaning to unimportant stimuli which causes hallucinations
- FRITH- METAREPRESENTATION DYSFUNCTION
ability to distinguish between the actions of others and your own.
this does not work properly in SZ people, which can lead to hallucinations of voices and though insertions (thinking you are hearing voices but it is just your own)>
it can also lead to delusions (thinking you are napoleon) - FRITH -CENTRAL CONTROL DYSFUNCTION
cognitive ability to supress automatic responses while performing deliberate actions
e.g., if you are speaking and you see a bird in the background, you will ignore it and carry on with conversation
symptoms like speech poverty and disorganisation could result in dysfunction of central control, as they cannot supress automatic thoughts leading to jump from topic to topic.
AO3 for cognitive explanation of SZ
+: RESEARCH SUPPORT FROM BRAIN SCANS
. reduced processing in ventral striatum is associated with negative symptoms.
reduced processing in temporal and cingulate gyrus is linked to positive symptoms like hallucinations
. impaired cognition linked to SZ
-: CORRELATION NOT CAUSATION
. not concrete- what if hallucinations cause this change in structure?
-: does not accommodate for biological factors.
psychological explanation is likely to be a proximal explanation, as it explains how the symptoms arise, but biological factors are more likely to be the distal explanation, the underlying cause of SZ. this suggests that it would then be better to focus on the biological underpinnings.
-: Meyer-Lindberg et al; found a link between then excess levels of dopamine in PFC, and dysfunctions of the working memory. WM dysfunction is associated with cognitive disorganisation traits common in SZ.
. this suggests that underlying biological factors cause SZ, and psychological dysfunction is only a product of biological abnormality
+: RESEARCH SUPPORT FROM STIRLING
gave sample of SZ and control group series of cognitive tasks including the Stroop test (central control function is needed). SZ ppts took twice as long on average to complete the task.
suggests cognitive processing is a common dysfunction in SZ
+: supported by effective cognitive treatments such as CBT- NICE metanalysis (CBTp more effective than antipsychotics)
. both focus on cognition- this suggests a cognitive cause of SZ.
external validity
-: treatment causation fallacy; an effective treatment does not completely support a psychological explanation (e.g., just because alcohol helps with shyness, this does not mean that shyness is caused by a lack of alcohol).
. CBTp emphasises giving patients methods to cope with SZ, so maybe this is what leads to reduction in symptoms, rather than its addressing of cognitive dysfunction.
