Explanations of schizophrenia

Question 1

what are the three biological explanations for schizophrenia?

Answer 1

-genetics
-neural correlates
-dopamine hypothesis

Question 2

what are the three conditions of research in genetic studies?

Answer 2

-family studies
-twin studies
-adoption studies

Question 3

what’s a piece of research on genetics using family studies?

Answer 3

Parmas et al 1993
longitudinal study, found 16% of kids who’s mum had schizophrenia developed it compared to 2% who’s mums didn’t have it

Question 4

what’s a piece of research on genetics using twin studies?

Answer 4

Gottesman + Shields 1976
concordance rates were 75-91% for monozygotic twins with severe schizophrenia, suggesting genetics play a bigger role in chronic forms

Question 5

what’s a piece of research on genetics using adoption studies?

Answer 5

Kety + Ingraham 1992
prevalence rates were 10x higher in genetic relatives than adoptive relatives suggesting genetics play a bigger role than the environment

Question 6

briefly evaluate the genetic explanation

Answer 6

-if it was purely genetic, concordance rates would be 100% in monozygotic twins
-small sample sizes make it hard to generalise (leo 2006)
-doesn’t consider other factors
-scientists portray it in a biased way (hedgecoe 2001)
-gene mapping can lead to further development

Question 7

what are neural correlates?

Answer 7

abnormalities in specific brain areas that can be associated with the development of schizophrenia. used scanning techniques. commonly found in schizophrenia:
-enlarged ventricles
-prefrontal cortex

Question 8

what was Boo et al’s 2012 research on neural correlates?

Answer 8

used MRI scnas on 155 schizophrenia patients, 186 of their mentally stable siblings and 122 non-related schizophrenia patients. found that people with the disorder had decreased grey matter and cortical thinning

Question 9

what are 2 pieces of neural correlates research that pinpoint brain locations?

Answer 9

-Juckel et al 2006 - abnormality in the ventrial striatum
-Ho et al 2003 - scanned patients with recent onset then rescanned them 3 years later, found the damage had worsened, especially in frontal lobes

Question 10

briefly evaluate the neural correlated explanation of schizophrenia

Answer 10

-some people without schizophrenia have enlarged ventricles, some people with schizophrenia don’t
-patients who don’t respond well to medication have enlarged ventricles
-must consider the environment
-only longitudinal research will show if damage worsens

Question 11

what is the dopamine hypothesis?

Answer 11

the neurotransmitter, dopamine, being linket to the onset of schizophrenia
dopamine controls the rate of firing neurons

Question 12

how was the dopamine hypothesis created?

Answer 12

it was discovered phenothiazine worked by decreasing dopamine levels

Question 13

what other neurotransmitter may be involved?

Answer 13

glutamate (reduced function of the NMDA glutamate receptor in schizophrenia patients, as dopamine receptors restrict the release of glutamate)

Question 14

how did Davis et al 1991 update the dopamine hypothesis?

Answer 14

not all schizophrenia patients have high dopamine levels, suggested high levels of dopamine in the mesolimbic dopamine system caused positive symptoms, while high levels in the mesocortical dopamine system caused negative symptoms

Question 15

what was Kessler et al’s 2003 research on the dopamine hypothesis?

Answer 15

used PET and MRI scans to compare people with schizophrenia to people without. found that people with it had elevated dopamine receptor levels in the basal forebrain and substantia nigra/ventral tegmental brain areas as well as differences in cortical dopamine levels

Question 16

what was Randrup and Munkvad’s 1966 research on the dopamine hypothesis?

Answer 16

they created schizophrenic-like behaviour in rats by giving them amphetamines (activates dopamine production) then reversed the effects by giving them neuroleptic drugs which inhibit dopamine release

Question 17

briefly evaluate the dopamine hypothesis

Answer 17

-evidence in inconclusive
-several neurotransmitters may be involved
-over-simplistic
-pharmaceutical companies are keen to see it promoted (Healy 2000)
-recovery is slow despite the fact that medication instantly decreases dopamine levels
-could be an effect of schizophrenia, not a cause

Question 18

what are the 3 dysfunctional characteristics expressed in family dysfunction?

Answer 18

-high levels of interpersonal conflict
-difficulty communicating with eachother
-being excessively critical and controlling

Question 19

what are 2 key phrases in family dysfunction?

Answer 19

-double-blind (bateson et al)(contradictory situations)
-expressed emotion (hostility and criticism)

Question 20

2 pieces of research on family dysfunction

Answer 20

-Tienari et al 2004 - 5.8% of kids adopted into healthy families developed the disorder compared to 36.8% adopted into unhealthy families
-Bateson 1956 - hospital visit from a mother exhibiting double-blind

Question 21

briefly evaluate the family dysfunction explanation of schizophrenia

Answer 21

-therapies that lower expressed emotion reduced relapse rates
-why do all kids in bad families not develop it if it was a sole explanation
-Bateson was accused of having selective bias
-schizophrenia can cause family dysfunction rather than the other way round

Question 22

what’s the cognitive theory of schizophrenia?

Answer 22

focuses on maladaptive thought processes
cognitive deficits (attention, communication and information overload)

Question 23

what role do Beck and Rector 2005 play in the cognitive explanation?

Answer 23

proposed a cognitive model that combined interactions between neurobiological, environmental, behavioural and cognitive factors to explain schizophrenia

Question 24

what does the cognitive explanation say causes positive symptoms?

Answer 24

cognitive biases
biased information processing
alien control symptoms

Question 25

what does the cognitive explanation say causes negative symptoms?

Answer 25

the use of cognitive strategies to control high levels of mental stimulation

Question 26

2 pieces of research on the cognitive explanation of schizophrenia

Answer 26

-Elvevag + Goldberg 2000 - schizophrenia is better characterised by cognitive deficits rather than symptoms
-Takahashi et al 2013 - compared electrical brain activity of 410 patients with schizophrenia to 247 patients without when exposed to auditory tunes

Question 27

briefly evaluate the cognitive explanation of schizophrenia

Answer 27

-cognitive theories don’t explain what led to cognitive dysfunctions
-may be possible to construct a specific cognitive deficit profile for better diagnosis
-accounts for both positive and negative symptoms
-can be combined with other explanations for a better understanding

Question 28

what is metacognition?

Answer 28

the cognitive monitoring of ones own thoughts which enables them to detect errors
it allows people to make sense of their lives and deal with changing environments

Question 29

2 pieces of research on dysfunctional thought processes

Answer 29

-Brune et al 2011 - reviewed 20 years of evidence, poor metacognition was evident
-Joshua et al 2009 - sentence completion test, 39 schizophrenia patients vs 40 without, the schizophrenia patients were slower

Question 30

how do dysfunctional thought processes relate to schizophrenia?

Answer 30

can lead to serious impairments in goal-directed behaviour, attention, memory, cognitive, flexibility, self-monitoring, inhibition of inappropriate responses and physical motor control of the body

Question 31

briefly evaluate the dysfunctional thought process explanation of schizophrenia

Answer 31

-therapies should focus on metacognitive abilities
-research suggests it occurs before onset
-Hemsey said the main problem was a disconnection between stored knowledge and new info
-some models combine with a neurological approach