Schizophrenia

Question 1

Schizophrenia

Answer 1

A type of psychosis characterised by a profound disruption of cognition and emotion so that contact with external reality and insight are impaired.

Question 2

Classification

Answer 2

Organising symptoms into categories based on which symptoms cluster together in sufferers i.e. what are the symptoms of schizophrenia?

Question 2

How common is schizophrenia?

Answer 2

The most common psychotic disorder, affecting 1% of the population at some point.
Most commonly diagnosed in males, city-dwellers and lower socio-economic groups.

Question 3

Diagnosis

Answer 3

Deciding whether someone has a particular mental illness using the classifications.

Question 4

Hallucinations

Answer 4

Disturbances of perception in any of the senses - either have no basis in reality or are a distortion of something that is real.

Question 5

Delusions

Answer 5

False beliefs not based in reality

Question 6

Positive symptoms

Answer 6

Atypical symptoms experienced in addition to normal experiences

Question 7

Negative symptoms

Answer 7

Atypical symptoms that represent a loss of a usual experience

Question 8

What is DSM-5 system?

Answer 8

-used in USA
-two of the positive symptoms must be present for diagnosis
-only one if delusions are bizarre
-only one if hallucinations consist of a voice with running commentary or two voices conversing
-continuous disturbances for at least a month
-at least one major area of function (work) must be below the previous level

Question 9

What is ICD-10 system?

Answer 9

-used in Europe
-two or more negative symptoms
-one positive symptom

Question 10

Symptom overlap

Answer 10

Occurs when two or more conditions share symptoms. Where conditions share many symptoms this calls to question the validity of classifying the two disorders separately.

Question 11

Co-morbidity

Answer 11

The occurrence of two disorders or conditions together, e.g. a person has both schizophrenia and a personality disorder. Where two conditions are frequently diagnosed together it calls into question the validity of classifying the two disorders separately.

Question 12

Osario et al. (2019) found inter-rater reliability of […] for DSM-5.

Answer 12

+0.97 (consistently applied)

Question 13

Osario et al. (2019) found test-retest reliability of […] for DSM-5.

Answer 13

+0.92 (consistently applied)

Question 14

Validity is the extent …

Answer 14

to which schizophrenia is a unique syndrome with unique characteristics, signs and symptoms (so whether it measures what it intends to measure).

Question 15

Serper et al. assessed …

Answer 15

patients with co-morbid schizophrenia and cocaine abuse, or either on its own.

Question 16

Serper et al. found …

Answer 16

Despite there being considerable symptom overlap in patients with schizophrenia and cocaine abuse, it was actually possible to make accurate diagnoses.

Question 17

Serper et al. findings suggest …

schizophrenia

Answer 17

Co-morbidity is not a significant issue

Question 18

Ketter points out …

schizophrenia symptom overlap

Answer 18

misdiagnosis due to symptom overlap can lead to years of delay in receiving relevant treatment, during which time suffering and further degeneration can occur, as well as high levels of suicide

Question 19

Ketter’s found …

schizophrenia symptom overlap

Answer 19

Symptom overlap can have serious consequences and focusing on fixing this issue could save money and lives.

Question 20

Ketter’s findings suggest …

Answer 20

Symptom overlap is a significant issue

Question 21

Bukely et al found …

co-morbidity schizophrenia

Answer 21

Around half of patients with a diagnosis of schizophrenia also have a diagnosis of depression (50%) or substance abuse (47%). PTSD also occurred in 29% of cases and OCD in 23%.

Question 22

Buckley et al findings suggest …

Answer 22

Co-morbidity is a significant (over 20%) issue

Question 23

General evidence for cultural bias in schizophrenia diagnoses…

Answer 23

African-Americans and English people of Afro-Caribbean origin are up to 10 times more likely to be diagnosed with schizophrenia. Given that rates in Africa and the West Indies aren’t high (ruling out a genetic vulnerability), the diagnosis seems to be the result of cultural bias.

Question 24

Escobar evidence for cultural bias …

Answer 24

White psychiatrists may tend to over-interpret the symptoms of Black people during diagnosis due to cultural differences in language and mannerisms, difficulties in relating, and the myth that black people rarely suffer from affective disorders.

Question 25

Longenecker evidence for gender bias …

Answer 25

reviewed studies of the prevalence of schizophrenia and concluded that since the 1980s, men have been diagnosed with schizophrenia more often than women. Prior to this, there had been no difference.

Question 26

Explanation for gender bias schizophrenia…

Answer 26

Female patients typically function better than men which may bias practitioners to under-diagnose schizophrenia either because their symptoms are masked or seen as mild due to good interpersonal functioning.

Question 27

What symptoms of schizophrenia overlap with bipolar?

5

Answer 27

• Hallucinations
• Delusions
• Lack of interest/pleasure (ahedonia)
• Difficultly concentrating/distractability
• Chronic depression/depressive episodes

Question 28

What did Gottesman’s find?

causes of schizophrenia

Answer 28

A large-scale family study and found much higher concordance rates in MZ twins (48%) in comparison to DZ twins (17%).

Question 29

What does the genetic explanation suggest about the cause of schiophrenia?

Answer 29

Thought to be polygenic (it requires a number of different genes to work in combination) and so different combinations of genes can lead to the condition. The most likely genes are those coding for neurotransmitters such as dopamine. Research suggests that there are 108 genetic variations associated with increased risk of schizophrenia.

Question 30

What does the genetic explanation also suggest about the cause of schiophrenia?

Answer 30

Schizophrenia can also have a genetic origin through the mutation of parental DNA by radiation, poison or viral infection.

Question 31

What are neural correlates?

Answer 31

Neural correlates are measurements of the structure or function of the brain that occur in conjunction with (correlate with) the characteristic symptoms of schizophrenia, and so may be implicated in the origins of schizophrenia

Question 32

What is the dopamine hypothesis and who proposed it?

Answer 32

Davis and Khan (1991) proposed a dopamine hypothesis, which gives us more neural correlates of schizophrenia.

Question 33

What changes does the dopamine hypothesis say cause schiophrenia?

level and area of brain

Answer 33

• Low level of dopamine in the prefrontal cortex
• High level of dopamine in Broca’s area (subcortex)

Question 34

What does low levels of dopamine in the frontal cortex lead to?

Schizophrenia

Answer 34

Responsible for thinking, emotions and decision making. Leads to avolition and cognitive symptoms

Question 35

What does high levels of dopamine in Broca’s area lead to?

Answer 35

High levels of dopamine in Broca’s area (subcortex)
Responsible for speech production.
Leads to speech poverty and auditory hallucinations.

Question 36

Why are schizophrenics beleived to have abnormally high dopamine levels?

Answer 36

Abnormally high levels of D2 receptors on post-synaptic neurons, resulting in more dopamine binding and therefore more neurons firing.

Question 37

How are genetics and stress believed to affect the dopamine hypothesis?

Answer 37

Genetic variations and early experiences of stress may make some people more sensitive to low levels of dopamine in the cortex and therefore high levels of dopamine in the subcortex.

Question 38

What is another neural correlate for auditory hallucinations?

Answer 38

Lower activation levels in the superior temporal gyrus and anterior cingulate gyrus have been found in those experiencing auditory hallucinations. Therefore, reduced activity in these two areas is a neural correlate of auditory hallucinations (positive symptom).