Schizophrenia

Question 1

Schizophrenia

Answer 1

Psychosis in the form of profound disruption to ones cognition and emotion, affecting language, thought, perception, emotions and sense of self.

Question 2

Positive Symptoms

Answer 2

An excess or distortion of normal functions. This includes hallucinations, delusions, disorganised speech, and disorganised of catatonic behaviour.

Question 3

Disorganised speech

Answer 3

Thoughts interrupt speech/ derail topics. Echolalia- rhyming words, Neologism- making up words.

Question 4

Catatonic behaviour

Answer 4

Inability to motivate or initiate a task, rigid postures or aimless motor activity.

Question 5

Negative Symptoms

Answer 5

Symptoms that reflect a reduction/ loss of normal function. This includes alogia, avolition, anhedonia and affective flattening.

Question 6

Alogia

Answer 6

Lessening of speech fluency and productivity.

Question 7

Avolition

Answer 7

Reduction of interest and desires.

Question 8

Affective Flattening

Answer 8

Reduction in the range and intensity of emotions.

Question 9

Anhedonia

Answer 9

Loss of interest in pleasurable activities.

Question 10

Milev et al 2005- defecit syndrome/ symptoms

Answer 10

Deficit syndrome = more than 2 negative symptoms for 12 months or longer. Those with deficit syndrome have more pronounced cognitive deficits and poorer outcomes.

Question 11

Makinen et al 2008- negative symptoms ratio

Answer 11

1 in 3 schizophrenics suffer with negative symptoms.

Question 12

Schizophrenia Diagnosis Kappa Score

Answer 12

According to Regier et al 2013 the diagnosis had a kappa score of 0.46.

Question 13

Reliability Cultural Differences

Answer 13

• Significant variations between countries when it comes to a SZ diagnosis.
• Copeland 1971- 134 US and 194 British psychiatrists a description of patients: 69% of the US ones diagnosed SZ, whereas only 2% of the British did.
• Luhrman et al 2015- interviewed 60 adults, 20 from each of Ghana, India and the US,. Those from Africa and India had positive experiences with their voices, where the American ones were violent and hateful- no consistent characteristics.

Question 14

Reliability- inter-rater

Answer 14

Whaley 2001- inter-rater reliability correlations in the diagnosis of SZ as low as 0.11 (kappa score).

Question 15

Reliability- unreliable symptoms

Answer 15

Mojtabi and Nicholson 1995- 50 senior psychiatrists differentiated between bizarre and non bizarre delusions, producing an inter-rater reliability of 0.4- subjective.

Question 16

Rosenhan et al 1972

Answer 16

Sent pseudo-patients to 12 different hospitals. They phoned the hospital for an appointment, stating that they had voices in their head that were ‘empty’, ‘hollow’ and ‘thud’. After they were admitted, they stopped stimulating symptoms and told staff that they were better. They remained in the hospital between 7 and 52 days (average of 19).

Question 17

Validity- gender bias

Answer 17

• Some diagnostic categories in the DSM may be more biased toward pathologising one gender due to research being more focused on one.
• Broverman et al 1970- clinicians in the US equated a mentally healthy adult behaviour with a male.
• Longenecker et al 2010- men have been diangosed with schizophrenia more often than women since the 1980s.
• Cotton et al 2009- female schizophrenics tend to function better than males.
• Loring and Powell 1988- 290 male and female psychiatrists read patients behaviour: when described as male or unspecified, 56% gave diagnosis, when described as female, 20% gave diagnosis.

Question 18

Validity- symptom overlap

Answer 18

• Many symptoms of schizophrenia are also prevalent in depression and bipolar disorder.
• Ellason and Ross 1995- pointed out that people with dissociative identity disorder have more schizophrenic symptoms than most diagnosed schizophrenics.
• Read 2004- most schizophrenics could also have at least one other diagnosis.

Question 19

Validity- co-morbidity

Answer 19

• Multiple disorders can occur at once in schizophrenics.
• Buckley et al 2009- estimate that co-morbid depression occurs in 50% of patients and substance abuse in 47%.
• Swets et al 2014- meta analysis showed that at least 12% of schizophrenics had OCD, 25% displayed symptoms.
• Calls into question whether it is a single condition.
• Weber et al 2009- analysed 6 million hospital discharge records and found thjat 45% had evidence of other disoders, but also found evidence of other non-psychiatric disorders like asthma or diabetes.

Question 20

Validity- prognosis

Answer 20

The prognosis varies with 20% recovering to their previous functioning, 30% showing improvement with some relapses and 10% achieving long lasting progress/ improvement. Diagnosis has little predictive value.

Question 21

Genetic Explanation

Answer 21

Schizophrenia tends to run in families, but only among individuals who are genetically related. It is thought that it is a combination of genes that make a person more vulnerable to developing schizophrenia.

Question 22

Family Studies (Gottesman and Shields 1991)

Answer 22

Children with two schizophrenic parents had a concordance rate of 46%, with one parent had a rate of 13% and with a sibling 9%.

Question 23

Twin Studies (Joseph 2004)

Answer 23

Calculated from a poll of all twin studies that MZ twins had a concordance rate of 40.4%, while DZ twins had a rate of 7.4%. More recent blind studies (researchers don’t know if they are MZ or DZ twins, concordance rates have been lower for MZ twins.

Question 24

Adoption Studies (Tienari et al 2000)

Answer 24

164 adoptees (biological mother had schizophrenia) 11 (6.7%) received a diagnosis compared to 4 (2%) of 197 control adoptees.

Question 25

The Dopamine Hypothesis

Answer 25

An excess of dopamine is associated with positive symptoms of schizophrenia. Schizophrenics are thought to have excess D2 receptors, resulting in messages from neurones associated with dopamine to fire too easily or too often. The revised hypothesis by Davis and Kahn in 1991 suggests that excess dopamine in the mesolimbic pathway causes positive symptoms, while a deficit in the mesocortical pathway causes negative symptoms.

Question 26

Drugs that increase dopaminergic activity

Answer 26

Amphetamines trigger dopamine-like symptoms in non-schizophrenics. These cause nerve cells to flood the synapse with dopamine, revealing that excess dopamine can cause positve symptoms.

Question 27

Antipsychotics

Answer 27

They block the activity of dopamine in the brain eliminating symptoms.

Question 28

Neural Imaging (Patel et al 2010)

Answer 28

Used PET scans to assess dopamine levels in schizophrenic and normal individuals and found lower levels in the dorsolateral prefrontal cortex of schizophrenics.

Question 29

Animal Studies (Wang and Deutch 2008)

Answer 29

Induced dopamine depletion in the prefrontal cortex of rats, resulting in cognitive impairment that could be reversed with atypical antipsychotics.

Question 30

Genetic Evaluation

Answer 30

+ Strong evidence to support it- Gottesman, Tienari, Joseph
- Common rearing patterns may explain family similarities
- MZ twins encounter similar environments/ treatment
- Adoptees may be selectively placed.
- Adoptees may be treated differently/ smothered by parents.

Question 31

Dopamine Hypothesis Evaluation

Answer 31

+ Strong evidence from treatment- Leucht et al (2013) carried out a meta-analysis of 212 studies finding that the drugs were more effective than placebos.
- Inconclusive supporting evidence- Moncrieff (2009) claims that evidence is far from conclusive- drugs affect multiple neurotransmitters and dopamine has not been found in post mortem examinations. Smoking or stress also increases the release of dopamine.
- Challenges to the dopamine hypothesis- Noll (2009) claims there is evidence against both hypothesise as drugs do not alleviate symptoms in 1/3 of patients. Some people also experience symptoms but have normal levels of dopamine.