Schizophrenia Flashcards
What are positive symptoms of schizophrenia
Symptoms that enhance the typical experience of sufferers, and occur in addition to their normal experiences
What are negative symptoms of schizophrenia
Symptoms that take away from the typical experience of sufferers, and represent a ‘loss’ of experience
Examples of positive symptoms
Hallucinations, delusions, disorganised speech, catatonic behaviour
Examples of negative symptoms
Alogia, Avolition, Affective flattening, and Anhedonia
Hallucinations
Bizarre, unreal perceptions of the environment that are usually auditory but can also be visual, olfactory, and tactile
Delusions
Bizarre beliefs that seem real to the sufferer but are not. Can be paranoid (being spied on), delusions of grandeur (believing they are a god), or delusions of reference (messages being communicated to them via the TV/radio)
Disorganised speech
The individual has problems organising their thoughts which shows in their speech.
The may jump from one topic to another (derailment) or may come across as talking gibberish
Catatonic behaviour
The inability to start a task, or complete it once started.
Alogia/speech poverty
The lessening of speech fluency and productivity –> reflects slowing or blocked thoughts
Avolition
A reduction of interests as well as the inability to initiate goal-directed behaviour, eg. sitting at home all day doing nothing
Affective flattening
A reduction in emotional expression, including facial expressions, voice tone, and body language
Anhedonia
The loss of interest/pleasure in all or almost all activities –> not enjoying physical pleasures (food, bodily contact) and/or social pleasures (interacting with other people)
Reliability
A diagnosis of schizophrenia must be repeatable –> two clinicians must reach the same conclusion at different points in time (inter-rater reliability)
Validity
Refers to whether an observed effect is a genuine one.
Symptom overlap
The fact that symptoms of a disorder may not be unique to that disorder, but may also be found in other disorders –> makes accurate diagnosis difficult
Comorbidity
When someone has more than 1 disorder at a time
Buckley et Al estimated that 50% or schizophrenia patients have co-morbid depression, and 47% have co-morbid substance abuse issues
Cultural differences in diagnosis (reliability - Copeland 1971)
Gave 134 US and 194 British psychologists the same description of a patient and found that 69% of the US psychologists gave a diagnosis, but only 2% of the British ones gave the same diagnosis
Gender bias (validity - Broverman 1970)
Found that clinicians in the US equate healthy behaviour to healthy male behaviour –> leads to more females being pathologised
AO3 Reliability of Diagnosis - Culture bias (Afro-Caribbean sufferers)
- In the UK, people of Afro-Caribbean descent are more likely than white people to be diagnosed as schizophrenic.
- Afro-Caribbean sufferers are more likely to be compulsorily confined in secure hospitals than white schizophrenics.
-Most British psychiatrists are white, and their unconscious biases could lead them to perceive black schizophrenics as more ‘dangerous’
-Heightened stress levels in ethnic minorities like poverty and racism could contribute to the higher levels of schizophrenia.
AO3 The consequence of Diagnosis
Being labelled schizophrenic has a long-lasting, negative effect on social relationships, work prospects, self-esteem etc., which seems unfair when diagnoses of schizophrenia are seemingly made with little evidence of validity.
Consequence of mis-diagnosis – receiving incorrect treatment has two issues.
1) correct disorder not being treated
2) side effects of drugs which are unnecessary
–> this leads us to question whether we should diagnosis at all
AO3 Culture bias (Rack 1982)
Points out that in many cultures, it is normal to see and hear recently deceased loved ones (it is part of the grieving process), but people exhibiting such behaviour in the West are liable to be diagnosed as schizophrenic.
This is similar with hearing the voice of God.
–> leads us to question the validity of scz diagnoses
AO3 Reliability of diagnosis (Beck et al)
- Performed a study on the reliability of psychiatric diagnosis using outpatients who were being considered for a research trial with his cognitive-behavioral therapy.
- Clinicians were asked to independently diagnose these outpatients and give reasons why they disagreed.
- Found that agreement on diagnosis for 153 patients between 2 psychologists was only 54%
- Clinicians mostly said the reason for the diagnostic disagreements is because of the overly broad and nonspecific diagnostic definitions.
AO3 Reliability of diagnosis - Issues with the criteria ‘bizarre’ (Mojtabi and Nicholson)
50 senior psychiatrists in the US were asked to differentiate between ‘bizarre’ and ‘non-bizarre’ delusions.
Inter-rater reliability correlation of +.40
To combat this, the DSM-V (2013) has been updated to make this more objective – the word ‘bizarre’ is no longer used.
Biological explanations (Genetics - Family studies)
- family studies have established that schizophrenia is more common among biological relatives of a person w/ the disorder
- the closer the degree of genetic relatedness, the greater the risk
Gottesman’s findings (Genetics - Family studies)
- Children w/ two schizophrenic parents had a concordance rate of 46%
- Children w/ one schizophrenic parent had a concordance rate of 13%
- Children w/ a schizophrenic sibling had a concordance rate of 9%
Biological explanations (Genetics - Twin studies)
If monozygotic twins have a greater concordance rate of schizophrenia than dizygotic twins, we can deduce that genetics play a role in schizophrenia
Joseph’s findings (Genetics - Twin studies)
- Found a concordance rate of 40.4% in monozygotic twins
- Found a concordance rate of 7.4% in dizygotic twins
Biological explanations (Genetics - Adoption studies)
- It is difficult to disentangle genetic and environmental influences for people that share both the same genes and environment
- Adoption studies combat this by studying people that share the same genes but are reared separately
Tienari’s findings (Genetics - Adoption studies)
- 7% of adoptees whose biological mothers had schizophrenia also received a diagnosis
- 2% of the control adoptees (whose biological mothers didn’t have schizophrenia) received a diagnosis
–> confirms the genetic influence on schizophrenia
Neural correlates
- Neural correlates in schizophrenia suggest that structures in the brain are associated with the positive and negative symptoms of schizophrenia
- Mainly focuses on dopamine
What does the dopamine hypothesis state
- an excess of dopamine in certain areas of the brain leads to the positive symptoms of schizophrenia
- sufferers are though to have an abnormal amount of D2 receptors, which leads to more dopamine binding and more neurons binding
Evidence for the dopamine hypothesis from Drugs
- amphetamine drugs cause the synapse to flood with dopamine
- when normal individuals were exposed to high amounts of these drugs, they developed characteristics symptoms of a schizophrenic episode, but the symptoms disappeared after the drugs wore off
- antipsychotics block the activity of dopamine in the brain
- when schizophrenics take antipsychotics that decrease dopaminergic activity, their symptoms are relieved, which supports the role of dopamine in schizophrenia
The revised dopamine hypothesis (Davis et AL)
Updated the theory because:
- High levels of dopamine are not found in all schizophrenics
- Clozapine has very little dopamine-blocking activity and still works effectively against the disorder
–> Davis et al. suggested that high levels of dopamine in the mesolimbic system are associated with positive symptoms, while abnormal levels in the mesocortical dopamine system are associated with negative symptoms.
Strengths of the Dopamine Hypothesis
+ Supports psychology as a science, evidence uses MRI and PET scans which produce objective evidence, scientific rigour.
+ Useful real-life application can help treat people and improve their quality of life. However, treatment-causation fallacy: if you have a headache and you take paracetamol, the headache is gone but the cause of the headache wasn’t a lack of paracetamol.
Weaknesses of the Dopamine Hypothesis
- Biologically reductionist (the lowest level/ most reductionist). Reducing a complex thing like schizophrenia to mere neural pathways –> diathesis stress model better
- Corruption! Pharmaceutical companies were keen to see the dopamine hypothesis promoted as they would make huge profits from manufacturing anti-schizo drugs.
-Antipsychotics are only effective at relieving positive symptoms, which suggests that the excess dopamine doesn’t cause schizophrenia but rather the positive symptoms. - lack of correspondence between taking the drugs and signs of clinical effectiveness –> takes 4 weeks to see signs that the drugs are working when they begin to block dopamine immediately - we cannot explain this time difference!
What are Neural Correlates
Changes in neuronal events and mechanisms that result in the characteristic symptoms of a behaviour or mental disorder.
Neural correlates - Enlarged Ventricles
- In 1927 it was found that 18/19 individuals with schizophrenia had enlarged ventricles (the larger the ventricles, the lower the brain cells)
- however, 30 years after initial onset, 35% of the schizophrenics are classified as “much improved“
–> if the reduction in brain volume is the cause of the schizophrenic symptoms then it cannot explain this because the cortex does not grow back!
Supporting evidence for neural correlates - Suddath et al (1990)
- used MRI to obtain pictures of the brain structure of MZ twins in which one twin was schizophrenic.
- found that the schizophrenic twin had enlarged ventricles and a reduced anterior hypothalamus
–> supports the role of neural correlates/brain structures in schizophrenia
Evaluation of genetic factors
- genetics are only partly responsible, otherwise identical twins would have 100% concordance rates - therefore we must consider the nurture side of the NvN debate and take an interactionist approach
- the genetic explanation of schizophrenia is biologically reductionist
What sociocultural factors can cause schizophrenia?
- Life events
- Family relationships
- schizophrenogenic
mother
- double-bind theory
- expressed emotion - Labelling theory
Life events - Brown and Birley 1968 (Sociocultural explanations)
- the occurrence of stressful life events has been linked to schizophrenic episodes
- B&B found that 50% of people experienced a stressful life event in the 3 weeks prior to a schizophrenic episode
The schizophrenogenic mother - Fromm-Reichmann (1948)
- she noted that many of her patients with schizophrenia described a parent that was: cold, uncaring, unemotional and controlling
- she thought this leads to stress and distrust, and later to paranoid delusions
Double-bind theory
- children who frequently receive contradictory messages from their parents are more likely to develop schizophrenia
- eg. parents who say they care whilst appearing critical or who express love whilst appearing angry
- prolonged exposure to this prevents the development of a coherent construction of reality and eventually manifests itself as schizophrenic symptoms
Expressed emotion
- a family communication style that involves criticism, hostility and emotional over-involvement.
- it is more important in maintaining schizophrenia than in causing it in the first place
Supporting research for the effects of EE
- Linszen et al (1997)
Found patients returning to a family with high EE is about 4 times more likely to relapse than a patient returning to a family with low EE
-Kalafi and Torabi (1996)
Found the high prevalence of EE in Iranian culture (overprotective mothers and rejecting fathers) was one of the main causes of schizophrenic relapses in Iran
Labelling theory
- The theory states that hallucinations, delusions and bizarre behaviour cause society to label these individuals as schizophrenic.
-Once a person has the label of schizophrenia, it becomes a self fulfilling prophecy. - The discrimination this causes increases the stress the schizophrenic will feel which can make the symptoms worse.
Evaluation of Family Dysfunction as an explanation for schizophrenia
+ 69% of women and 59% of men with schizophrenia in their sample had a history of physical and/or sexual abuse in childhood
- EE doesn’t consider individual differences: Individual differences – not all patients who live in high EE families relapse and not all patients in low EE families avoid relapse –> incomplete explanation
Strength of EE - Real Life application (family therapy)
- understanding the impact our family and environment can have on relapse or development of schizophrenia, allows us to prevent this from occurring when patients return home. - eg. family therapy teaches relatives how to create a healthy supportive surrounding for the sufferer, subsequently avoiding relapse.
-preventing relapse has benefits to the economy as it means less patients are hospitalised and allows them to lead healthy fulfilled lives after treatment.
