relevant research and evidence relating to the topic of Schizophrenia for AQA Psychology B PSYB3
Includes research relating to:
Biological explanations,
Cognitive explanations,
Sociocultural explanations,
Treatments
Gottesman et al (1991)- suggested that
schizophrenia is inherited through genetic
inheritance
Twin studies- concordance
rates of 46% for MZ twins and
14% for DZ twins.
Cardno (2002) showed a
concordance rate of 26.5% for
MZ twins and 0% for DZ twins.
Joseph et al (1991) showed
concordance rates of 40% for
MZ twins and 7.4% for DZ twins
Family studies- the closer the
genetic link the higher the
chances of developing
schizophrenia
Adoption studies- Tiennari (2000) out of a
sample of 164 adoptees who's mother was
diagnosed with schizophrenia, 6.7% also
recieved the same diagnosis compared to 2%
of the 197 control group
Heston (1966) found a concordance
rate of 16% within children of
schizophrenic mothers.
NEUROANATOMICAL
Szesko et al - found asymetry in normal
brains, this is missing within people with
schizophrenia.
Andreasen et al (1990) found significantly
large ventricles within the brains of
schizophrenic men.
Liberman et at (2001) found the same results
Weyandt (2006) suggested a relation to
negative syptoms
Jernigan et al (1991) found
significant cell loss within the
limbic system- Hippocampus
and amygdala
Nasrallah at el (1986) the gender difference in the
thickening of the corpus callosum is reversed in
schizophrenic patients
NEUROCHEMICAL
Seeman et al (1993) found a 6X higher
density in D4 receptors in the brains of
schizophrenics
Pearlson et al (1993) found a significant
increase in D2 receptors in the brains of
schizophrenic patients
COGNITIVE
HALLUCINATIONS
Fowler (2007) found that there is a high
incidence of child abuse or trauma in patients
diagnosed with schizophrenia
Slade and Bentall (1988) five
factor model suggests that
hallucinations decrease anxiety
Close and Garety (1998)
suggested the opposite
DELUSIONS
Bentall (1991) suggested that
paranoid and persecutory
hallucinations are a defence
against depression and low self
esteem
Zimbardo (1981) stated that delusions occur
to make sense of a situation and may happen
to people without schizophrenia
SOCIOCULTURAL
LABELLING THEORY
Scheff (1966) proposed the idea that
schizophrenia is a learned social role acquired
through labelling
Szasz (1962) - once a person is labelled as schizophrenic
it influences their behaviour and become a self- fulfilling
prophecy
Rosenhan (1973) once labelled as
schizophrenic, normal behaviours are
seen to be as a result of the disorder.
FAMILY DYSFUNCTION
Brown et al (1958) - patients discharged
into the care of family were at a higher
risk of relapse than those that live alone
due to the increased face to face contact
between the patient and family
50% chance of relapse in high EE
families compared to 21% in low EE
families
Butzlaff and Hooley (1998) found that
70% of schizophrenics relapsed within 1
year in high EE families compared to
30% in low EE families
Bateson et al looked at family dynamic and
suggested that communication between parents
and children were contradictory ; this is referred to
as a Double Bind.
Nomura et al (2005) found that when a person recovering from the active
phase of schizophrenia goes back to a family with high EE, the person is
likely to relapse
TREATMENTS
BIOLOGICAL
Loeble et al (1992) found that 16% of
patients fail to respond to conventional
neuroleptics
Meltzer (1999) found that up to 66% of patients with
stubborn symptoms respond within 12 moths of
starting Clozapine (an atypical neuroleptic)
BEHAVIOURAL
Paul and Lentz (1977) found a significant
improvement in interpersonal skills and
self care in a token economy programme
Birchwood and Spencer (1999) SST
improved patients' ability, comfort and
assertiveness in social situations