Schizophrenia

• What is schizophrenia?

  A mental disorder characterised by psychosis

  > patients find it difficult to distinguish between reality & their own thoughts
• What are positive symptoms?

  Symptoms that are an excess or distortion or normal experiences

  > they are in addition to your ordinary existence
• What are two positive symptoms?

  Hallucinations =

  > distorted sensory experiences

  > can be related to any sense but commonly involves: hearing voices (auditory) or seeing things that do not exist (visual)

  Delusions =

  > belief or thought that is untrue & irrational

  > common delusions are paranoia about being controlled by an external force or being persecuted & delusions of grander (e.g. believing you are the messiah)
• What are negative symptoms?

  These are symptoms that are a loss of normal functions & experiences
• What are two negative symptoms?

  Speech Poverty (Alogia) =

  > speech becomes lessened and/or disorganised

  > can be difficult to produce words or sentences

  Avolition =

  > apathy towards achieving goals

  > patients suffer a lack of motivation characterised by poor hygiene, lack of persistence in work/education & lack of energy
• What are the two classification systems used for diagnosis?

  > ICD-10/11

  > DSM-V
• What is the ICD-10/11 classification system?

  Used by the World Health Organisation (WHO)

  > requires 2 or more negative symptoms for a diagnosis
• What is the DSM-V classification system?

  Used by American Psychiatric Association (APA)

  > requires one positive symptom for diagnosis
• How are family studies used to explain the development of Schizophrenia? (Biological Explanation)

  If one family member has Schizophrenia then the chance of another member being diagnosed with it increases as they become more genetically similar

  > Grossman (1991) found identical twins have 48% concordance rate, fraternal twins 17% & parents 6&

  *in comparison to general population = 1%
• How can candidate genes explain the development of Schizophrenia? (Biological Explanation)

  Schizophrenia is polygenic so a combination of genes may cause it

  > believed that genes responsible for coding dopamine neurotransmitters are most likely to be involved
• How can mutations cause Schizophrenia to develop? (Biological Explanation)

  Can be caused by a mutated gene of a parent through radiation, viral infection or poisoning
• Evaluate genetic explanations?

  (+) Adoption Studies

  > Hiker found a concorbance rate of 33% for identical twins & 7% for fraternal twins even though they were adopted - genetic basis

  (-) Environment

  > concordance rate for twins is not 100% so genetics is not the sole explanation

  > Morkved found 67% of patients had experienced childhood trauma

  (-) Diagnostic Criteria

  > Cardno used 'Maudsley Twin Register' which uses strict diagnostic criteria

  > found concordance rate of 26.5% for MZ twins & 0% for fraternal twins

  > cannot compare studies using different criteria
• What is a neural correlate?

  Patterns of structure or activity in the brain that occur in conjunction with an experience

  > may be implicated in the origins of that experience
• What is the original Dopamine Hypothesis?

  Hyperdopaminergia

  > excess levels of dopamine receptors in pathway between subcortex to Broca's area cause speech poverty & auditroy hallucinations (positive symptoms)
• What is the new Dopamine Hypothesis?

  Hypodopaminergia

  > low levels of dopamine in prefrontal cortex causing problems with thinking & decision making (negative symptoms)

  > leads to hyperdopaminergia in subcortex
• What is the Ventral Striatum?

  Reward center in the brain

  > Juckel (2006) measured activity levels & found lower levels of activity in schizophrenics compared to controls
• What are the Superior Temporal Gyrus & the Anterior Cingulate Gyrus?

  Reduced activity in these parts of the brain is a neural correlate for auditory hallucinations (Allen 2007)
• Evaluate neural correlates?

  (+) Drug Therapy

  > antipsychotics reduce symptoms by reducing symptoms by reducing dopamine

  > amphetamines increase dopamine which worsens symptoms

  > evidence for dopamine hypothesis

  (-) Glutamate

  > McCutcheon (2020) found schizophrenics have deficiency in glutamate function

  > could have a more important role in Schizophrenic symptoms

  (-) Correlations

  > does not imply causation

  > studies cannot explain why these areas have higher or lower activity
• What is the schizophrenogenic mother aspect of the family dysfunction explanation of schizophrenia?

  Fromm - Reichmann (1948) = Psychodynamic Explanation

  > explains that a mother who is cold, rejecting & controlling can cause schizophrenia in her child

  > she creates an environment of tension & secrecy leading to child's distrust & later develops into paranoid delusions
• What is the double-bind theory of the family dysfunction explanation of schizophrenia?

  > children who receive contradictory messages from their parents are more likely to develop schizophrenia

  > they fear they are doing the wrong thing but get mixed messages about what this is

  > children find this confusing & can cause symptoms like disorganised thinking & paranoid delusions
• What is the expressed emotion (EE) aspect of the family dysfunction explanation of schizophrenia?

  A high EE household contains factors which can worsen schizophrenic symptoms & cause relapse:-

  • Verbal Criticism
  • Hostility
  • Emotional Overinvolvement
• Evaluate the family dysfunction explanation?

  (+) Research Support for Double Bind

  > Berger (1965) found schizophrenics reported higher recall of double bind statements made by their mothers than non-schizophrenics

  (-) Lack of Evidence

  > theories of schizophrenogenic mother & double bind have no systematic evidence to support them

  > only based on informal assessments

  (-) Socially Sensitive

  > theories use parent blaming effectively to explain the causes of schizophrenia & child's relapse

  > blaming parents makes the theories open to interpretation
• What is the cognitive explanation for the development of schizophrenia?

  Explained throught different types of dysfunctional thinking

  > evidence shows reduced functioning in areas such as the ventral striatum or temporal & cingulate gyri (cognition) is impaired
• What are the two types of dysfunctional thought processing?

  > Metarepresentation Dysfunction

  > Central Control Dysfunction
• What is the metarepresentation dysfunction explanation for schizophrenia?

  Experienced as having difficulty in recognising that our own behaviours/thoughts are being carried out by ourselves rather than another person

  > explains symptoms such as hallucinations & delusions
• What is the central control dysfunction explanation for schizophrenia?

  Inability to suppress our automatic thoughts/responses & speech is triggered by our own thoughts

  > explains symptoms like speech poverty
• Evaluate the cognitive explanation?

  (+) PET Scans

  > show under activity in frontal lobe of the brain which is linked to self-monitoring which schizophrenics have less control over

  (+) Research Support

  > Stirling (2006) found schizophrenics took twice as long to complete Stroop test suggesting impaired cognitive processing

  (-) Diathesis Stress Model

  > cognitive explanations are good for explaining symptoms but there are also genetic origins for these impairments

  > more interactionist approach may be better to explain schizophrenia
• What is inter-rater reliability in relation to diagnosis?

  Refers to the extent that two clinicians will reach the same diagnosis
• What is test-retest reliability in relation to diagnosis?

  Whether the same diagnosis is reached for the same individual on two occassions by one clinician
• What is reliability of diagnosis?

  Historically it has been low but recent studies suggest higher reliability

  > Osario (2019) found inter-rater reliability of +.97 & +.92 for test-retest reliability
• What is validity of classification & diagnosis?

  Refers to extent that a diagnosis represents something that is real & distinct from other disorders & whether ICD or DSM measure what they claim to measure

  > Cheniaux (2009) found when two psychiatrists assessed same clients using both ICD & DSM they found that schizophrenia may be over or under diagnosed:-

  • 68 were diagnosed with ICD
  • only 39 were diagnosed under DSM
• Evaluate the classification & diagnosis of schizophrenia?

  (-) Co-Morbidity

  > diagnosed alongside other conditions as 50% also have depression, 47% substance abuse & 23% OCD - Buckley (2009)

  > diagnosis & treatment difficult as it may not be a distinct disorder

  (-) Gender Bias

  > more men diagnosed than women due women having more social support & functioning better

  > leads to underdiagnosis & lack of treatment for women
• Evaluate the classification & diagnosis of schizophrenia?

  (-) Symptoms Overlap

  > many symptoms similar to other disorders (e.g. bipolar)

  > may not be two separate conditions but variations of the same one

  (-) Culture Bias

  > symptoms interpreted differently in different cultures

  > African-Caribbean British people 9 x more likely to be diagnosed than White British > diagnostic system may be culturally biased
• What are typical antipsychotics?

  Dopamine Antagonists as they reduce levels of dopamine in brain by blocking dopamine receptors

  > initially dopamine levels build up but over time production decreases

  > reduces positive symptoms

  > created in 1950's & taken orally

  > dosages start low & increase to 400 - 800 mg

  > have a sedating effect on patients & can be used to calm patients in hospital

  > e.g. chlorpromazine, primozide
• What are atypical antipsychotics?

  Act on dopamine, serotonin and glutamate receptors

  > treat negative & positive symptoms

  > created in 1970's

  > have less side effects than typical antipsychotics

  > useful in treating those at risk of suicide for this reason

  > e.g. clozapine, risperidone
• Evaluate drug therapy?

  (+) Research Support

  > Meltzer (2012) found clozapine is more effective than typical & other atypical antipsychotics

  > reduced symptoms in 30 - 50 % of patients who didn't improve with typical antipsychotics

  (-) Side Effects

  > many side effects including agitation, weight gain & tardive dyskinesia which involves involuntary facial movements

  > many stop taking drug due to this

  (-) Dopamine

  > we do not fully understand why these drugs work

  > research suggests suggests low levels rather than high could cause schizophrenia

  > so may not be the best treatment for all
• What does CBT consist of?

  > Helping patients to identify irrational thoughts & tries to change them

  > 5-20 sessions individually or as a group session

  > Explaining to the patient where their symptoms come from & how this impacts their own feelings
• How is Ellis' Rational Emotive Behaviour therapy used in CBT?

  By 'disputing' the patients' thoughts by using 'reality testing'

  > this is when they examine together the likelihood that their irrational beliefs are true
• What are the two types of psychological treatments?

  > cognitive behaviour therapy

  > family therapy
• Evaluate cognitive behavioural therapy?

  (+) Evidence

  > Jauhar (2014) reviewed results of 34 studies of CBT & concluded it has a significant but fairly small effect on positive/negative symptoms

  (-) Not a Cure

  > CBT may just allow a patient to cope better with their symptoms but does not cure biological origin of the condition (lots of evidence)

  (-) Range of Techniques

  > different therapists use different types of CBT & patients can have very varied symptoms

  > difficult to ascertain how effective CBT would be for each individual