Schizophrenia

schizophrenia

serious mental disorder suffered by 1% of population

positive symptoms

atypical symptoms experienced in addition to normal experiences

* hallucinations
* delusions
* disorganised speech

negative symptoms

atypical experiences that represent a loss of usual experience

* avolition
* speech poverty

Evaluation of diagnosis and classification of schizophrenia

\- co-morbidity

* schizo often co-morbid with other conditions like depression (schizoaffective disorder)

\- no objective test

* Cheniaux et al (2009) demonstrated inter-rater reliability was poor with 1 psychiatrist diagnosing 26% with schizo and the other 13% (using DSM)

\+ ,medical approach to diagnosing and classifying schizo has led to range of effective treatments

psychological explanations

* dysfunctional family
* cognitive explanations

schizophrenogenic mother (Fromm-Reichmann, 1948)

mothers said to be cold, rejecting, overprotective, moralistic about sex and fearful of intimacy

* **distrust, resentfulness and instability caused by such parent leads to schizophrenic reaction**

Sanity, Madness and the Family (R.D. Laing)

suggested schizophrenia was cause by family dysfunction and poor parenting

* case study: child believed she was a tennis ball in perpetual game of tennis with her parents

Evaluations of family dysfunction as an explanation

\- mothers who fit this criteria did not always produce schizophrenic women (like Maslow), many schizophrenics also did not have such mothers

* due to idiographic approach of research

\- family dysfunction theories were base on psychodynamic theories, an approach that was losing credibility

double bind theory (Bateson, 1972)

parents often communicate contradictory and confusing feelings to children developing distorted views of world

* **double bind position in which a child might feel compelled both to act and not act in a certain way at the same time**

based on case studies and interviews

\- flawed research methodology

expressed emotion

**negative family communication style**

* critical comments through both tone and content, emotional over involvement etc

**if these factors are high, risk of relapse is high**

Support for family dysfunction as risk factor

\+ Read (2005) reviewed 46 studies of child abuse and schizophrenia in adulthood and concluded 69% of adults inpatients with schizophrenia had a history of child abuse

dysfunctional thought processes (Frith, 1992)

schizophrenics fail to monitor their own thoughts correctly, misattributing them to outside world

* when a person hears voices, it is actually their own inner speech being misinterpreted = may lead to auditory hallucinations and delusions

metarepresentation

ability to recognise one’s thoughts, s**chizophrenics often have impaired metarepresentation**

psychological treatments

* CBT
* Token economies
* Family therapy

CBT

attempts to challenge irrational thinking in a collaborative and constructive way

* **cognitive restructuring**
* **reality testing**
* **normalisation**

Evaluations of CBT as a psychological treatment

\+ Jauher et al (2014) reviewed results of 34 studies and concluded CBT had a significant but small effect on both positive and negative symptoms

\- help patients challenge/understand symptoms whilst drug therapies reduce severity of symptoms

\- may be ineffective due to schizophrenic’s symptoms

Family therapy

aims to reduce high levels of expressed emotion in the family and improve general communication

* focuses on reducing hostility, over-involvement, critical comments
* therapeutic alliance is necessary

Evaluation of family therapy as psychological treatment

\+ reduces risk of relapse

\+ **Pharoah et al** concluded there is moderate evidence to show family therapy significantly reduces hospital readmission

\- therapeutic alliance is harder to form due to presence of multiple family members

token economies

reward based systems

based on principles of behaviourist approach (operant conditioning)

Biological explanations

* **genetic vulnerability**
* **dopamine hypothesis**
* **neural correlates**

Gottesman (1991)

* 12 studies across 8 countries
* ranging 60+ years with approx 2000 pairs of twins

**= closer a family relationship was, more likely they shared schizophrenia**

MZ twins = 48%

DZ = 17%

Evaluation of Gottesman (1991)

\+ large scale, longitudinal, both contributing to validity

\+ supporting evidence (**Tienari et al 2004** adopted children with schizo biological mothers more likely to develop schizo than adopted kid without)

\- higher concordance between MZ could be explained by greater environmental similarity than genetic

How is schizophrenia aetiologically heteregenous?

Can be caused by different combinations of genes, including those coding for functioning of neurotransmitters (incl dopamine) such as COMT gene

Dopamine hypothesis

dysregulation of dopamine = symptoms of schizophrenia

hyperdopaminergia

excess of dopamine in subcortex (Broca’s area)

* related to disorganised speech and auditory hallucinations

hypodopaminergia

lack of dopamine in prefrontal cortex

* related to negative symptoms such as avolition

Evaluation of dopamine hypothesis

\+ amphetamines and cocaine = dopamine agonists which can cause hallucinations and delusions in non-schizophrenics and make schizophrenic symptoms worse

\+ antipsychotics (dopamine antagonists) reduce dopamine levels and eliminate hallucinations and delusions, strengthening case of dopamine being contributory factor

\- post-hoc fallacy

\- simplistic as there are many neurotransmitters involved such as glutamate

\+ post-mortems revealed higher than normal levels of D2 dopamine receptors in brains of schizophrenics

neural correlates

areas/circuits of the brain that are related to schizophrenia

* ventral striatum
* superior temporal gyrus
* anterior cingulate gyrus

neural correlates of negative symptoms

lower levels of activity in **ventral striatum** linked to development of avolition

* ventral striatum = involved in anticipation of reward.
* abnormalities here would result in lack of motivation

neural correlates for positive symptoms

reduced activity in **superior temporal gyrus and anterior cingulate gyrus** linked to development of auditory hallucinations

evaluation of neural correlates

\- difficulty to establish cause and effect, malfunction in neural correlates may be a result of having schizophrenia not vice versa

\- biologically reductionist as it tries to explain a complex multi-faceted disorder at the levels of just biology. (neglects diathesis stress model)

agonist

molecule capable of binding to and functionally activating a target

antagonist

molecule that binds to a target and prevents other molecules from binding

types of antipsychotics

* atypical
* typical

typical antipsychotics

* usually have worst side effects


* developed in 50s

==**Chlorpromazine**==

* antagonist in dopamine system, blocks dopamine receptors in synapses in the brain, reducing action of dopamine

atypical antispychotics

* improved effectiveness and minimised side effects
* developed in 70s
* target a range of neurotransmitters

==**Clozapine**==

* binds to serotonin, glutamate and dopamine receptors (antagonist)
* reduces depression and anxiety as well as improving cognitive functioning

==**Risperidone**==

* binds to dopamine and serotonin receptors as an antagonist, down regulating their effect
* binds more strongly and therefore is more effective in smaller doses

Evaluation of drug treatments for schizophrenia

\- chlorpromazine fails to solve negative symptoms as it focuses solely on dopamine, could make negative symptoms worse

\- effect of side effects

\+ Claghorn et al (1987) found clozapine is therapeutically superior to chlorpromazine

\+ more time efficient than attending therapy, making it more accessible

\- ethical issues as it can be used as sedation (human rights abuse)

\- does not highlight and solve causes of schizophrenia, only treats symptoms

interactionalist approach for schizophrenia

treatments should combine psychotherapy and drug therapy to provide best results

* drugs make patients more receptive to psychotherapy
* however, bio causes are not clear enough that drug treatments are always used