Schizophrenia

• What is schizophrenia?

  A mental disorder characterised by psychosis. Patients find it difficult to distinguish between reality & their own thoughts.
• Positive Symptoms of Schizophrenia:

  • These symptoms are in excess or distortion of normal experiences.
  • Hallucinations: Distorted sensory experiences, Can be auditory (hearing voices) or visual (seeing things).
  • Delusions: A belief or thought that is untrue & irrational. Common delusions are paranoia about being controlled by external forces, being persecuted or delusions of grandeur i.e. I am the messiah
• Negative Symptoms of Schizophrenia:

  • These symptoms are a loss of normal functions & experiences
  • Speech Poverty (Alogia): Speech becomes lessened/ is disorganised. Difficult to pronounce words or sentences
  • Avolition: Apathy towards achieving goals. Patients suffer a lack motivation characterised by poor hygiene, lack of persistence in work/education and lack of energy
• Diagnosis of Schizophrenia:

  • ICD-10/11 Classification System: Used by WHO (World Health Organisation). Requires 2 or more negative symptoms
  • DSM-V Classification System: Used by American Psychiatric Association (APA). Requires 1 positive symptom for diagnosis.
• Reliability:

  • Inter-rater reliability refers to the extent that two clinicians will reach the same diagnosis
  • Test-retest reliability is whether the same diagnosis is reached by the same person on 2 occasions by the same clinician
  • Osario et al. (2019) found scores of +.97 & +.92.
• Validity:

  • Validity refers to the extent that a diagnosis represents something real & distinct from other disorders, and whether the ICD or DAM measure what they claim to measure.
  • Cheniaux et al. (2009) found when 2 psychiatrists assessed the same clients, 68 were diagnosed with ICD and only 39 under the DSM
  • Depending on system, schizophrenia may be over or under diagnosed

  
• What is Co-Morbidity?

  • The extent to which two (or more) conditions occur at the same time in a patient
  • Schizophrenia is diagnosed with other conditions

  1. 50% also have depression
  2. 47% substance abuse
  3. 23% OCD

  • This makes diagnosis & treatment difficult, and schizophrenia may not even be a distinct disorder
• Gender Bias in Schizophrenia:

  • More men are diagnosed than women but some argue women have better social support so function better (Cotton et al. 2009)
  • This leads to underdiagnosis & a lack of treatment for women

  
• How does Symptom Overlap affect Schizophrenia diagnosis?

  Some Schizophrenia symptoms are found in other disorders, such as bipolar disorder. Therefore, it could be that they are not two separate conditions but different variations of the same condition.
• Culture Bias in Schizophrenia:

  • Symptoms can be interpreted in different ways by different cultures
  • Afro-Caribbean British people are 9 times more likely than White British people to be diagnosed
  • Diagnostic system may be culturally biased
• Genetic Explanations - Family Studies:

  • MZ twins have a 48% concordance rate for schizophrenia
  • DZ twins = 17%
  • Parents = 6%
• Genetic Explanations - Candidate Genes:

  • Schizophrenia appears to be polygenic in that a combination of different genes may cause it
  • Its believed genes that code dopamine neurotransmitters are likely the cause
• Genetic Explanation - Mutation:

  • Even if there's no family history of Schizophrenia, it could be caused by a mutated gene via a mutagenic agent
  • Such as through radiation, viral infection or poisoning
• Evaluation of Genetic Explanations:

  • Environment - The fact that concordance rate for twins isn't 100% suggests an environmental component
  • Cardno et al (1999) used the 'Maudsley Twin Register' which has stricter diagnostic criteria. Concordance rate for MZ twins was 26.5%, & was 0% for DZ twins. We can't compare with different criteria
  • Adoption Study - 33% concordance rate for MZ twins, 7% for DZ twins suggesting a genetic basis.
• Neural Correlates - Dopamine Hypothesis:

  • Hyperdopaminergia = Excess dopamine receptors in the pathway from the subcortex to the Broca's Area, cause speech poverty/auditory hallucinations
  • Hypodopaminergia = Low levels of dopamine in the prefrontal cortex causing problems with thinking & decision making
• Neural Correlates - Ventral Striatum

  • Used in anticipation of reward
  • Found lower activity in schizophrenics
• Neural Correlates - Superior Temporal Gyrus & Anterior Cingulate Gyrus:

  • Reduced activity in these parts of a brain correlates for auditory hallucinations
• Evaluation of Neural Correlates:

  • Drug Therapy - Antipsychotics reduce symptoms by reducing dopamine. Amphetamines worsen symptoms by increasing dopamine. This gives evidence for the dopamine hypothesis
  • Glutamate - Found schizophrenics have a deficiency in glutamate function.
  • Correlations - Correlation doesn't equal causation. These studies don't explain why these areas have higher/lower activity.
• Family Dysfunction - Schizophrenic Mother:

  • Fromm-Reichman (1948) psychodynamic explanation explains that a mother who is cold, rejecting & controlling can cause schizophrenia
  • She creates an environment of tension & secrecy, which leads to the child's distrust which later develops into paranoid delusions
• Family Dysfunction - Double-Bind Theory

  • Children who get contradictory messages from parents about what's right and wrong may develop schizophrenia
  • The confusion & fear causes disorganised thinking and paranoid delusions
• Family Dysfunction - Expressed Emotion (EE)

  • A high EE household contains

  1. verbal criticism
  2. hostility
  3. emotional overinvolvement

  • This can worsen schizophrenic symptoms & cause relapse
• Evaluation of Family Dysfunction:

  • Parent Blaming - these theories are socially sensitive
  • Support for Double Bind - Found schizophrenics reported a higher recall of double bind statements made by their mothers, than non-schizophrenics
  • Lack of Evidence - These theories are only based on informal assessments, not actual evidence
• Cognitive Explanations:

  • Schizophrenia can be explained through different types of dysfunctional thinking
  • Evidence shows reduced functioning in the ventral striatum and temporal/cingulate gyri & thus cognition (thinking) is impaired
• Cognitive Explanations - Metrarepresentation Dysfunction

  • This is having difficulty in recognising our behaviours are being carried out on ourselves rather than other people
  • Explains symptoms such as hallucinations & delusions
• Cognitive Explanations - Central Control Dysfunction

  • The inability to suppress our automatic thoughts and feeling, and the speech triggered by thoughts
  • Explains the symptom speech poverty
• Evaluation of Cognitive Explanations:

  • PET Scans - Shows reduced activity in frontal lobe, which is linked to self-monitoring
  • Research Support - Found schizophrenics took twice as long to complete the Stroop Test, suggests impaired cognitive processing
  • Diathesis-Stress Model - Although cognitive explanations are good for explaining symptoms, schizophrenia does have genetic components. So it may be better to take an interactionist approach.
• Antipsychotics - Typical Antipsychotics

  • Created in the 50s & taken orally
  • Known as 'dopamine antagonists' as they reduce dopamine by blocking receptors
  • They have a sedating effect on patients & can be used to calm patients down in hospitals
  • Examples = Chlorpromazine, Pimozide
• Antipsychotics - Atypical Antipsychotics

  • Created in the 70s & have less side effects that typical antipsychotics
  • They can treat both positive & negative symptoms by also acting on serotonin and glutamate receptors
  • It is useful in treating those at risk of suicide
  • Examples = Clozapine, Risperidone
• Evaluation of Drug Therapy:

  • Side Effects - Many don't take drugs due to agitation, weight gain & involuntary facial movements
  • Evidence - Found clozapine (an atypical antipsychotic) as it reduces symptoms in 30%-50% of patients who didn't improve with typical antipsychotics
  • Dopamine - We don't fully understand how these drugs work
• Cognitive Behaviour Therapy

  • Helps patients identify irrational thoughts
  • 5-20 sessions individually or with a group
  • Explains to patients where their symptoms come from & how this impacts their feelings
  • Some therapists use Ellis' Rational Emotive Behaviour Therapy by disputing patients thoughts using 'reality testing' i.e. proving that these beliefs are irrational

  
• Evaluation of Cognitive Behaviour Therapy:

  • Not a Cure - CBT helps the patient cope with symptoms, not cure the condition
  • Evidence - Meta-analysis of 34 studies showed the effect are significant but fairly small on symptoms
  • Range of Techniques - Different therapists use different CBT types with varying symptoms & effectiveness. Therefore, we can't compare
• Family Therapy:

  • Therapy with both the family & the patient, aims to encourage communication to reduce relapse rates
  • It is done by reducing levels of 'Expressed Emotion', especially anger & guilt, to reduce stress in the home.
  • They're also educated about Schizophrenia & are giving practical coping skills
• Evaluation of Family Therapy

  • Evidence - Relapse rates were reduced by 50-60%, & is especially effective when the illness is in its early stage
  • Family Benefit - Involves everyone in the therapy
  • Economic Implications - Reducing relapse rates takes the pressure of other healthcare services & benefits the state
• Token Economies

  • Based on operant conditioning & is an example of behaviour modification. A token is given when a desirable behaviour is shown as a reward (secondary reinforcer) which can later be exchanged for a tangible reward (primary reinforcer)
  • This technique is used for institutionalised patients with bad habits to boost their quality of life & to prepare them for outside life
  • Used internationally more
• Evaluation of Token Economies:

  • Not a cure - Doesn't address symptoms or root of schizophrenia
  • Hard to Maintain in the outside world - 'Token Economies' don't really exist
  • Ethical Issues - Enables clinicians to have power over patients lives & discrimination occurs as those with more severe symptoms won't attain as many tokens
  • Evidence - Analysis of 7 studies found a reduction in undesirable behaviour & negative symptoms
• Diathesis-Stress Model

  • This model states that schizophrenics have a genetic predisposition & an environmental trigger
  • This is an example of an Interactionist Approach, as it combines biological, psychological and social factors
  • It advocates for combined treatment with drugs and therapy
• Diathesis-Stress Model - Meehl's Model

  • States the vulnerability was a schizogene and anyone with the gene is susceptible to stress and developing schizophrenia (especially if their mother is schizophrenic)
• Diathesis-Stress Model - Modern Understanding

  • Now we understand that genes may contribute to vulnerability and even childhood trauma can be the vulnerability
  • Stressors also can extend beyond the idea of parenting e.g. the use of cannabis
• Evaluation of Diathesis-Stress Model:

  • Overly simplistic - Many biological and psychological causes = very complex
  • Evidence - Adopted Finnish children who had biological mothers with schizophrenia AND adoptive parents who were hostile, critical, and had low empathy were more likely to develop the disorder
  • Treatment - Participants with medication & CBT had less symptoms than the medication only group. No difference, however, in hospital admissions