Schizophrenia Flashcards
Schizophrenia
Term first used by Bleuler to categorise patients whose thought processes and emotional responses seemed disconnected (spectrum disorder)
How many people does schizophrenia affect?
1 in 100
International Classification of Diseases (ICD-10)
Produced by WHO (World Heath Organisation) , used as a diagnostic tool and to analyse and monitor the general health of the population
Diagnostic and Statistical Manual (DSM-5)
Produced by American Psychiatric Association, diagnose mental illness
Catatonic
classified by disturbance to movement leaving sufferer immobile
Paranoid
classified by powerful delusions and hallucinations
Hebephrenic
classified by native symptoms
How many symptoms must be present in order to diagnose a patient?
two for six months or more, active for at lease one month
Positive symptoms
represent change in behaviour or thoughts which affects or distorts their sense of reality, very distressing
Negative symptoms
can be present for several years before diagnosis - prodromal stage, appear gradually and slowly get worse. Reflect a diminution or loss of normal functioning
Positive symptoms- hallucinations
involve all the senses, common is hearing voices; abusive, assertive or annoying
Positive symptoms- delusions
held with extreme conviction despite being obviously untrue and unlikely, come as a result of hallucinations
Delusions of grandeur
individual believes they have some power or authority over the next
Positive symptoms- disorganised thinking
thoughts will drift from one thing to another, no connection between, words become jumbled (word salad)
Negative symptoms- speech poverty
social withdrawal, difficulty speaking to people
Negative symptoms- avolition
difficulty in planning and setting goals, no motivation, no interest in socialising
Negative symptoms- anhedonia
loss of interest or pleasure in all or almost all activities
Negative symptoms- affective flattening
reduced range of facial expressions and tone of voice
Problem with Negative symptoms
hard to distinguish from laziness
Co-morbidity
refers to the extent that two or more conditions or diseases occur simultaneous in a patient
Buckley (2009)
found that those diagnosed with schizophrenia were also diagnosed with other disorders
Buckley found that what % of those diagnosed with schizophrenia were also diagnosed with depression?
50%
Buckley found that what % of those diagnosed with schizophrenia also were diagnosed with OCD?
23%
Reliability
consistency of measurements and repeatability
Cultural differences in diagnosis - Copeland (1971)
gave 134 US and 194 British psychiatrists a description of a patient - 69% of US diagnosed schizophrenia but only 2% of British
Validity
whether an observed effect is a genuine one
Gender bias
when accuracy of diagnosis is dependent on the gender of an individual
Gender bias - Broverman (1970)
found that clinicians in the US equated mentally healthy ‘adult’ behaviour with mentally healthy ‘male’ behaviour = tendency for women to be perceived as less mentally ill
Symptom overlap
refers to the fact that symptoms of a disorder may not be unique to that disorder but are found in others
Evaluation of validity: research support for gender bias
Loring and Powell (1988) - randomly selected 290 male and female psychiatrists to read two case vignettes of patients’ behaviour, asked judgement. Described as males or no info on gender - 56% diagnosed schizophrenia, when female - only 20% given diagnosis
Evaluation of reliability: lack of inter-rater reliability
Whaley (2001) found inter-rater reliability correlations as low as 0.11
Both DSM-5 and ICD 10 are emic constructs. What is this?
a test that is created and tested in one country, meaning that its construct may only reflect the norms and values of that culture
Imposed etic
imposing the judgements and values of one culture onto another
Ethnocentric
assumption that there is no difference between cultures (culturally biased)
Genetic factors - Kendler et al (1985)
found that the first-degree relatives of those with schizophrenia were 18 times more likely to develop the disorder
Family Studies: Gottesman (1991)
children with two schizophrenic parents had a concordance rate of 46%, children with one schizophrenic parent a rate of 13% and siblings a concordance rate of 9%
Twin Studies: Joseph (2004)
if monozygotic twins are more similar than dizygotic, then this suggests that the greater similarity is due to genetic factors. Concordance rate for monozygotic twins of 40.4% and 7.4% for dizygotic twins
Adoption Studies: Tienari (1991)
164 adoptees’ biological mothers had been diagnosed with schizophrenia, 11 also received a diagnosis of schizophrenia, compared to just 4 of the 197 control adoptees
Evaluation of genetic factors: twin studies
Joseph argued the difference in concordance rates between monozygotic and dizygotic twins reflects the environmental differences that distinguish twin types due to identical twins being treated more similarly - hereditary factors not valid
Evaluation of genetic factors
Biological approach as a whole is reductionist
The Dopamine Hypothesis
excess of the neurotransmitter dopamine in certain regions of the brain is associated with the positive symptoms of schizophrenia
What do schizophrenics have abnormally high numbers of on receiving neurons?
D2 receptors, resulting in more dopamine binding and therefore more neurons firing, leading to hallucinations and delusions
Drug that increases dopaminergic activity
Amphetamine - stimulates nerve cells containing dopamine, causing synapse to be flooded with neurotransmitter
Drug that decreases dopaminergic activity
Antipsychotics, such as olanzapine - block the activity of dopamine in the brain, eliminating symptoms
The Revised Dopamine Hypothesis - Davis and Kahn (1991)
Positiive symptoms are caused by an excess of dopamine in subcortical areas of the brain and -ive arise from a deficit of dopamine in areas of the prefrontal cortex
Animal Studies - Wang and Deutch (2008)
induced dopamine depletion in the prefrontal cortex in rats - resulted in cognitive impairment that researchers were able to reverse using antipsychotics
Evaluation of dopamine hypothesis: weakness
neuroleptic drugs do not work for all patients diagnosed suggesting it is not just dopamine that causes symptoms
Evaluation of dopamine hypothesis: weakness of brain scans
in 1990s, did not find that people suffering have more dopamine receptors
Evaluation of dopamine hypothesis - strength
successful drug treatments - Leucht’s meta analysis of 212 studies analysing the effectiveness of antipsychotic drugs
Evaluation of dopamine hypothesis - weakness of D2 receptors
blocking the D2 receptors of individuals has little to no effect on their symptoms suggesting other neurotransmitter symptoms may also produce positive symptoms associated with schizophrenia
Family Dysfunction
schizophrenia develops as a result of poor communication or faulty relationships within the family
Double bind theory
Bateson et al (1956) - suggest that children who frequently receive contradictory messages from their parents are likely to develop schizophrenia
Expressed emotion
family communication style likely to influence relapse rates
Cognitive explanations of delusions
egocentric bias leads person to relate irrelevant events to themselves
Cognitive explanations of hallucinations
hypervigilance (auditory stimuli) leads to higher expectancy for the occurrence of a voice than normal individuals
Evaluation of family dysfunction - importance of family relationships
Tiernari et al found disturbed adoptive families more likely to trigger schizophrenia in children with genetic vulnerability
Evaluation of double bind theory
Berger (1956) - schizophrenics reported higher recall of double bind statements than non-schizophrenics
Evaluation: individual differences vulnerability to EE
not all schizophrenics respond negatively to high EE and not all patients who live in low EE homes avoid relapse
Evaluation of cognitive explanations - supporting evidence
Sarin and Wallin (2014) - found evidence that +ive symptoms arise from faulty processes such as impaired self-monitoring
Evaluation - support for cognitive therapies
CBT more effective at reducing symptom severity than antipsychotics
Typical drug therapy
typical antipsychotics are dopamine antagonists, used to combat +ive symptoms, block action of dopamine
Atypical drug therapy
atypical antipsychotics combat +ive and -ive symptoms, show rapid dissociation from D2 receptor and a stronger affinity for serotonin receptors
What % of D2 receptors must be blocked for antipsychotics to be effective?
between 60% and 70%
Evaluation of antipsychotics - weakness
typical impact on areas of the brain that control motor activity - extrapyramidal side effects
Evaluation of antipsychotics - ethical weakness
cost-benefit analysis may be negative, human rights abuse because of side effects
Evaluation of antipsychotics - no difference?
Crossley et al conclude no difference in efficacy of typical and atypical but more severe side effect for atypical
Cognitive Behavioural Therapy for psychosis (CBTp)
form of psychotherapy that aims to identify and challenge the faulty and irrational thought processes so they are replaced with rational thoughts
How can the ABCDE model be used to challenge irrational thoughts?
Identify the events that prevent the person achieving their life goals (activating agent). Acknowledge their belief system and the consequences. Irrational thoughts are then disputed. Rational thoughts are then created (effects)
Evaluation of CBTp - effectiveness
Startup et al (2004) - found that after one year those who had received CBT were better able to manage their +ive and -ive symptoms
Evaluation of CBTp - lack of availability
Haddock et al suggests only small proportion of people are offered CBTp
Family Therapy
takes part at home, coping strategies are developed so whole family can deal with symptoms, discussion is encouraged about day-to-day problems, experiences are shared.
KEY STUDY: Pharaoh et al (2010) procedure
meta-analysis - reviewed 53 studies in Europe, Asia and North America, compared outcomes from family therapy to standard care. Research concentrated on studies that were randomised controlled trials
KEY STUDY: Pharoah et al (2010) findings
use of family intervention increased patients’ compliance with medication, family intervention did not appear to have much affect on employment and independence. Moderate evidence that it significantly reduces hospital readmission and improved quality of life.
Evaluation of family therapy - strength
Tarrier et al (1989) - may improve a patient’s overall social functioning
Evaluation of family therapy - weakness of Pharoah
possibility of observer bias where raters were not ‘blinded’ to the condition to which people were allocated
Token economies
involve analysing the patient’s faulty behaviour patterns with the aim of changing the behaviour through reinforcement, rewards and even punishment
Name the type of conditioning used in token economies
operant conditioning
How do token economies work?
1) Tokens are paired with rewarding stimuli and so become secondary reinforcers. 2) Patient engages in ‘target’ behaviours or reduces inappropriate ones. 3) Patient is given tokens for engaging in these target behaviours (e.g. dressing themselves). 4) Patient trades these tokens for access to desirable items or other privileges.
Evaluation of token economies - strength
provide patients with the incentive to behave in appropriate ways
Evaluation of token economies - weakness
method lacks external validity - therapy is only effective in controlled environments where behaviour can be carefully monitored
Evaluation of token economies - ethical concerns
clinicians may exercise control over important primary reinforcers such as food, privacy or access to activities that alleviate boredom
Diathesis-Stress Model
schizophrenia occurs as a result of a genetic predisposition or vulnerability to the disorder and an environmental factor that triggers the disorder
Evaluation of the diathesis-stress model - strengths
integrates different explanations - not a reductionist and do not ignore complex nature of human behaviour
Evaluation of the diathesis-stress model - weaknesses
difficult to investigate how the two factors interact, more hypothetical and does not have predictive power of scientific explanations - lacks reliability and validity
KEY STUDY: Ripke et al (2014) - Candidate Gene Procedure
Completed a study combining all data from a genome wide study of schizophrenia.
KEY STUDY: Ripke et al (2014) - Candidate Gene Findings
37,000 paitents were compared to 113,000 controls. 108 separate genetic variations were associated with an incresed risk of schizophrenia
KEY STUDY: Goldman-Rakic et al (2004) - Dopamine Hypothesis (Hypodopaminergia old)
Abnormal dopamine systems in the brain cortex. Identified a role for the low levels of dompamine in the prefrontal cortex. Affects negative symptoms of schizophrenia as it effects thinking and decision making.
KEY STUDY: Juckel et al (2006) - Neural correlates with Negative symptoms
Lower activity levels of compared to controls.Activity in the ventral striatum has been linked to the development of avolition (loss of motivation)(Negative symptom of schiz). The ventral striatum are believed to be particularly involved in the anticipation of a reward for certain actions. Negative correlation between activity levels in the ventral striatum and the severity of overall negative systems
KEY STUDY: Allen et al (2007) - Neural correlates with Positive symptoms
Reduced activity in the superior temporal gyrus and anterior cingulate gyrus have been linked to the development of auditory hallucinations. Patients experiencing auditory hallucinations showed lower activation levels in these areas than controls. Therefore, reduced activity in these areas of the brain is a neural correlate of auditory hallucinations
KEY STUDY: Fromm-Reichmann (1948) - Schizophrenogentic Mother
Early theorists influenced by Freudian ideas, thought that a ‘schizophrenogenic mother’, who was cold, dominant and created conflict, caused schizophrenia to emerge in the child. These mothers were said to be rejecting, overprotective, selfsacrificing, moralistic about sex and fearful of intimacy. The distrust, resentfulness and instability caused by such a parent creates a family climate characterised by tension and secrecy. This leads to distrust that later develops into paranoid delusions (i.e. the belief that one is being persecuted by another person), and ultimately schizophrenia.
KEY STUDY: Read et al (2005) - Support for Family Dysfunction as a risk factor
Reviewed 46 studies of child abuse and schizophrenia and concluded that 69% of adult women in-patients with a diagnosis of schizophrenia had a history of physical abuse, sexual abuse or both, in childhood. • Men- 59% • Berry et al. (2008) adults with insecure attachments are more likely to have schizophrenia.
KEY STUDY: Turking et al (2004) - Evidence for CBT
CBT was used to challenge paranoid delusions: E.G. Patient: The mafia are observing me to decide how to kill me Therapist: You are obviously very frightened…there must be good reason for this Patient: Do you think it’s the mafia? Therapist: It’s a possibility, but there could be other explanations. How do you know it’s the mafia?
KEY STUDY: Read et al (2001) - Neural Development Model
Proposed a neurodevelopmental model in which early development in which early trauma alters the developing brain. E.g. The hypothalamic-pituatry-adrenal system (HPA) becomes over-active and the person is more vulnerable to later stress
KEY STUDY: Meehl’s Model
Believed diathesis was entirely genetic, the result of a single ‘schizogene’. This led to the development of a biologically based schizotypic personality, one characteristic is sensitivity to stress. According to Meehl, if a person doesn’t have the schizogene then no amount of stress would lead to schizophrenia. However, in carriers of the gene, chronic stress through childhood and adolescence, particularly a schizophrenic mother could result in schizophrenia.
KEY STUDY: Turkington et al (2006) - Both neural and Biological causes
it is perfectly possible to believe in biological causes and still practice CBT to relive psychological symptoms. Treatment would need to be adapted
KEY STUDY: Frith (1992) - Dysfunctional in meta representation
Frith suggested that people with schizophrenia fail to monitor their own thoughts correctly, misattributing them to the outside world. When a person hears voices, it is actually their own inner speech being misinterpreted, however, sufferers may believe that someone or something in the external world is communicating with them. Such processing problems in people with schizophrenia are sometimes referred to as alien control symptoms because the sufferer feels as if external forces are influencing their thoughts and actions and they have no personal control.
