Schizophrenia Clinical characteristics Issues in the classification and diagnosis of schizophrenia Biological explanations and treatments Psychological explanations and treatments

Clinical characteristics Positive symptoms add to the experience Hallucinations (auditory, visual, etc.) Delusions (of grandeur, influence, passivity, etc.) Negative symptoms retract from the experience Reduced care for personal hygiene Social withdrawal

Issues in the classification and diagnosis of schizophrenia Reliability Validity

Reliability Carson – the publication of the DSM-III resolved problems of inter-rater reliability because clinicians now had a reliable classification system Wilks et al. – RBANS test used to diagnose schizophrenia has high test-retest reliability at +0.84

Evaluation Whaley – DSM is rarely used to diagnose disorders and has low inter-rater reliability when used (+0.11) “Bizarre” delusions are specified in the DSM but what counts as “bizarre”? 50 psychologists had an inter-rater reliability of just on this Prescott et al. – test-retest reliability for attention tests in schizophrenia was stable over 6 months Copeland – 69% US psychiatrists gave a schizophrenia diagnosis whereas only 2% of UK psychiatrists did

Validity Comorbidity Buckley et al. – 50% of schizophrenics suffer from comorbid depression; 47% suffer from long-term substance abuse Schizophrenia may go undiagnosed and untreated Subtypes of schizophrenia – all one disorder or many different disorders?

Evaluation Weber et al. – patients diagnosed with schizophrenia have lower standards of healthcare, so physical illnesses may make them appear worse Individuals labelled with “residual” schizophrenia find it difficult to get jobs Rosenhan found that patients could easily be labelled schizophrenic but couldn’t get rid of the label Harrison et al. – Afro-caribbean groups 8x more likely to be diagnosed as schizophrenic

Biological explanations Neurochemical factors Neuroanatomical factors

Neurochemical factors The dopamine hypothesis Too much dopamine causes schizophrenia Could be too many receptors or oversensitive receptors Phenothiazines – drugs that block dopamine receptors and decrease sz symptoms L-dopa – parkinson’s medication that increases dopamine and increases sz symptoms

Evaluation Phenothiazines aren’t 100% effective and only help positive symptoms so there must be some other [psychological] factor involved L-dopa doesn’t increase schizophrenic symptoms Difficult to assess cause and effect - brain structure assessed post-mortem could be affected by long-term medication

Neuroanatomical factors Reduced cerebral blood flow to frontal lobes causes altered gait Abnormal limbic system causes emotionlessness Symmetrical prefrontal cortices is abnormal Enlarged ventricles in male schizophrenics

Evaluation PET, CAT, fMRI scans are not reliable Crow’s types of schizophrenia resolve issues in biological explanations: Type 1: genetic, dopamine-based, acute, positive, responds well to medication Type 2: neurodevelopmental, pre- or perinatal insults, chronic, negative, doesn’t respond well to medication Biological reductionism

Biological treatments Antipsychotics ECT

Antipsychotics Conventional antipsychotics (e.g. chlorpromazine) Block dopamine (D 2 ) receptors Atypical antipsychotics (e.g. clozapine) Temporarily block dopamine and serotonin receptors Both reduce positive symptoms

Evaluation Effectiveness Davis et al. – 55% of patients relapsed on a placebo compared to 19% on antipsychotic medication Antipsychotics are more effective in patients with hostile families Appropriateness Conventional antipsychotics cause serious side effects including tardive dyskinesia, constipation and hypotension. These are 30% common and irreversible in 75% of cases Antipsychotics treat symptoms not the disorder, leading to a revolving door effect

ECT ECT is very rare but still used to treat schizophrenia in extreme cases: 1.Barbiturate administration and oxygen supply 2.Unilateral or bilateral electrodes placed 3.Electric current passed for ½ a second 4.3 times a week for 5 weeks

Evaluation Effectiveness APA – actual ECT produced the same results as antipsychotic medication Sarita et al. – no difference between ‘sham’ ECT and actual ECT Appropriateness Harmful side effects including death, brain damage and memory impairment mean ECT is rarely used Read – 59% decline in ECT use from

Psychological explanations Cognitive explanations Psychodynamic explanations

Cognitive explanations Frith Mechanisms in meta-representation are faulty leading to an inability to generate and monitor willed action so individuals cannot distinguish between externally & internally generated action leading to the development of positive symptoms Hemsley Failure to activate schema means individuals don’t know what to expect from situations so interpret superficial events as highly relevant leading to delusions Failure to activate schema also means attributing internally generated thoughts to external sources leading to hallucinations

Evaluation Faulty mechanisms in meta-representation can be targeted in therapy Dysfunctional thought processing may be an effect rather than cause of schizophrenia Dysfunctional thought processing links cognitive and biological explanations in one neuropsychological approach Decreased schema activation may not be and entire memory impairment – the central executive and visuospatial sketchpad are most affected Hemsley’s research was on non-human animals, and thus inapplicable to humans

Psychodynamic explanations The cold, rejecting ‘schizophrenogenic’ mother creates a fragile ego The ego cannot handle the demands of the id & superego so breaks apart Cannot distinguish between self & others, desires/fantasies & reality Regression to a pre-ego stage of primary narcissism

Evaluation Schizophrenogenic mothers are not a reliable predictor of schizophrenia Psychodynamic approach is outdated and difficult to test Therapies for schizophrenia based on this approach are ineffective Accounts for sociocultural factors so is strong in this sense

Psychological treatments Cognitive-behavioural therapy (CBT) Family intervention

CBT CBT is used to identify and correct faulty interpretations of events CBT techniques include:- Tracing back to origins of symptoms to understand how they developed Encouraging evaluation of delusions/hallucinations and considering how the validity of these might be tested Setting behavioural assignments to improve general levels of functioning Looking for alternative explanations of maladaptive beliefs already in the patient’s mind

Evaluation Effectiveness Gould et al.’s meta analysis – statistically significant decrease in positive symptoms following CBT CBT is given whilst patients are on antipsychotic medication – is the effectiveness of CBT or these drugs being measured?

Evaluation Appropriateness CBT decreases the distress when positive symptoms are experienced. Negative symptoms may be a coping mechanism for these, and so are decreased as well. Some psychiatrists suggest that some schizophrenics would not fully engage with CBT

Family intervention The aim of family intervention is to make family life less stressful and so reduce rehospitalisation Family intervention techniques Forming an alliance with carers Reducing emotional climate Enhancing relative’s ability to anticipate and solve problems Maintaining reasonable expectations for patient behaviour

Evaluation Effectiveness Pharoah’s meta-analysis – mixed results on the outcome of mental state; increased compliance with medication; increased general but not social functioning NICE meta-analysis – family intervention reduces severity of symptoms and hospital admissions

Evaluation Appropriateness The cost of family intervention is offset by the reduced cost of fewer hospitalisations during and after treatments Data on hospitalisation is from non-UK settings where clinical practice is different and so may not be applicable