Schizophrenia: AO1 Flashcards
Positive Symptoms and Examples
- symptoms that reflect an excess or distrotion of normal functions
- hallucinations: sensory experiences of stimuli that aren’t real or distorted perceptions of things which are real, people report hearing voices
- delusions: irrational beliefs that have no basis in reality, often people believe themselves to be historical or popular figures, paranoid delusions are beliefs that the person is being persecuted, people often believe themselves to be under external control
Negative Symptoms and Examples
- symptoms that reflect a loss or decrease of normal functions
- speech poverty: reduced frequency and quality of speech, disorganised speech: sentences which change subject half way through
- avolition: loss of motivation and low activity levels, difficulties with goal directed behaviour, commonly include poor personal hygiene, problems at work or school
Family Study of Genetic Explanation
Gottesman (1991):
- meta analysis of 40 studies investigating family history of SZ
- found closer degree of genetic relatedness, greater risk
- children with 2 SZ parents have concordance rate of 46%, children of one have 16% and siblings have 8%
Twin Study of Genetic Explanation
Gottesman & Shields (1966):
- 57 pairs of twins with at least one having SZ
- assessed using hospital notes, case histories, semi structured interviews with twins and parents
- concordance rate of 54% for MZ and 18% for DZ
Key Study: Tenari (1966)
Procedure: nationwide sample of adopted children, 1 group had bio mothers with SZ, matched control group who had bio mothers without, families assessed by interviews
Findings: 29% of children with bio mothers with SZ went on to develop symptoms compared to 16%, of 7 severe cases 6/7 were children of bio parent with SZ, across both groups level of symptoms strongly correlated with level of disturbance in adoptive family
Conclusion: diathesis stress model: genetic and environmental contribution
The Dopamine Hypothesis: Hyperdopaminergia
- excess of dopamine in subcortical regions particularly mesolimbic pathway associated with positive symptoms
- dopamine function elevated by brain producing abnormally high amount of dopamine and/or too many dopamine receptors on post synaptic neuron
The Dopamine Hypothesis: Hypodopaminergia
- too little neurotransmitter in the mesocortical pathway is associated with the negative symptoms
- modern refinement
Enlarged Ventricles
- Johnstone et al (1976) used CT scans to examine brains of 17 SZ patients and compared them to age matched non SZ patient
- found enlargement of ventricles common in people with SZ and the enlargement was most severe in those with most severe symptoms
Season of Birth Effect
- the idea that people born in the late winter and spring have a higher chance of getting schizophrenia due to their mothers being in their 2nd trimester during the winter when they are more likely to get a viral infection
- this infection may damage the brain of the unborn child directly or medicine taken by the mother could damage the unborn child
The Schizophrenogenic Mother
- Fromm-Reichmann (1948)
- noticed people with SZ often referred to mothers as cold, rejecting, controlling and domineering which leads to excessive stress
- SZ mothers create a family climate of tension and secrecy, leading to distrust and can later develop into paranoid delusions and psychotic thinking
- fathers often play passive role in such families
Double Bind Theory
- Bateson et al (1972)
- SZ caused by parents giving contradictory messages and child feeling like they can never do the right thing
- child receives verbal affection and non verbal animosity
- these interactions prevent construction of an internally coherent construction of reality resulting in disorganised thinking and paranoia
Expressed Emotion and Features
- defined as family relations characterised by hostility, criticism, over involvement and over concern
- hostility: the family feels that the disorder is controllable and that the patient is choosing not to get better, problems in the family are often blamed on the patient
- emotional over involvement: family behaviour often involving over protectiveness, self sacrifice and excessive use of praise or blame, intrusive and emotional behaviour towards the patient poor communication with the patient: much talking and little listening, over bearing behaviour
- critical comments: both hostile and emotional over involvement
Meta-representation
- the cognitive ability to reflect on thoughts and behaviour
- the ability to separate your thoughts and behaviours from those of others
- allows insight into own intentions and goals and interpret actions of others
- SZ patients have impaired MR: disrupts ability to recognise own actions as carried out by themselves
Central Control
- ability to suppress automatic responses while performing deliberate actions
- ability to concentrate
- SZ patients have impaired CC
Attentional Bias
- when people with SZ pay too much attention to irrelevant stimulus
- may result in delusions
Typical Antipsychotics
- discovered to be effective in 1950s and led to development of dopamine hypothesis
- block D2 dopamine receptors
- reduces positive symptoms such as hallucinations and delusions
- 70-90% receptors blocked
Atypical Antipsychotics
- became available in 1970s
- block D2 receptors
- rapidly dissociate to allow normal dopamine transmission
- block serotonin receptors
- fewer side effects
- reduce positive and negative symptoms
CBT
- basic assumption is that people with schizophrenia often have distorted beliefs which influence feelings and behaviours in maladaptive ways such as delusions about being watched and controlled
- aims to help people establish links between thoughts, feelings or actions and symptoms and general level of functioning
- sz patients encouraged to trace back origins of positive and negative symptoms to see how they developed, set behavioural assignments to improve level of functioning
CBT Phases
1) assessment: patient expresses thoughts about experiences, realistic goals discussed eg recognising delusions internal or finding coping mechanisms such as making appointments with voices
2) engagement: therapist emphasises with ps perspective and feelings of distress and stresses explanations can be developed together
3) ABC model: patient gives explanation of activating events that appear to cause emotional and behavioural consequences, beliefs then rationalised, disputed and changed to realise delusions are false
4) normalisation: info that many people experience symptoms helps patient feel less isolated as voice hearing is normal
5) critical collaborative analysis: therapist uses gentle questioning to help patient understand illogical deductions and conclusions eg asking for evidence for hallucinations and delusions
6) developing alternative explanations: patient develops own alternative explanations such as identifying adverse life events which could help reduce symptom severity particularly delusions
