Schizophrenia Flashcards
The DSM diagnostic criteria for schizophrenia is that 2 or more of the following symptoms must be present for a sig portion of time during a 1 month period:…
1) Delusions, 2) Hallucinations, 3) Disorganised speech, 4) Grossly disorganised or catatonic behaviour (all +ve symptoms) & 5) -ve symptoms
What are the different phases during which +ve & -ve symptoms may occur?
Prodromal (preclinical), active (+ve symptoms most likely) & residual (-ve & cognitive outcomes of the psychotic episode)
Name 3 common delusions. Delusions of…1), 2) & 3). Delusions are cognitive ___ of abnormal experiences
Control (of the mind/body by an external force), persecution (X wants to harm you) & reference (remarks, events or objects have special meaning). Explanations
Name 3 common auditory hallucinations:…
Audible voices (say the patient’s thoughts out loud), commentary (of the patient’s actions) & voices arguing (2 voices arguing with each other)
Give 3 other commons signs of “thought disorder” (3 delusions about your own thoughts)
1) Thought insertion (by an outside force), 2) Thought withdrawal (by an outside force) & 3) Thought broadcast (paranoia that one’s own thoughts have been inserted into others’ minds)
What do we mean by disorganised speech?
The production of speech which is incoherent & incomprehensible due to loosening of semantic associations between concepts. The patient may catch onto the sound but not the meaning of a question asked
What do we mean by catatonic behaviour?
Disturbances of movement including rigidity, bizzare posturing & repetitive imitations of others’ movements - which fit with the notion of DA dysfunction
Give 3 -ve symptoms
1) Affective flattening (lack of mood), 2) Alogia (lack of speech) & 3) Avolition (lack of general desire)
Give 2 points which suggest that schizophrenia may not be one disorder
1) No one symptom/ collection of symptoms characterises all patients, 2) All the component symptoms of S can be found in other psychological or medical conditions. I.e. symptoms lack consistency & exclusivity
It is possible that S is a group of disorders with different biological causes producing similar/related behavioural symptoms because the DSM…
Classifies disorders on the basis of behaviour only (not biology)
Around .%-_% of the population suffer from S. It occurs equally in…& in…
0.5%-1%. All cultures & both genders
Are there any typical gender differences in S?
Yes in the nature of how the disorder manifests itself. Men: earlier onset, more schizotypical traits prior to onset, more -ve symptoms (vs. +ve symptoms for women), more often chronic & unresponsive to treatment than when diagnosed in females
Define endophenotypes
Brain markers of underlying genetic factors
Is S entirely genetically determined? How was this demonstrated in quadruplet S patients?
No. These quadruplets all suffered from S but their illnesses varied in severity & they showed symptom & neuropsychological differences. Whether early brain injury or harsh childhood treatment caused these differences is unknown
The average risk for developing S in the population is 1%. What is the % risk for 1) spouses of patients, 2) first cousins (12.5% genes shared = 3rd degree relatives), 3) 2nd degree relatives e.g. nephews (25% genes shared) & 4) first degree relatives e.g. offspring of S parents & siblings/DZ twins vs. MZ twins
1) 2% (due to the shared environment or assortative matching), 2) 2%, 3) 4% & 4) 16.6%, 17% vs. 48% N.B. 3) changes with the amount of shared environment
Griffith (1972) found that amphetamine can mimic psychosis after - days in…when administered every hour for 5 days
2-5 days. Experienced amphetamine users
Postmortem studies inconsistently show abnormalities in the ___ of dopamine
Metabolities (substances required to chemically process dopamine)
Name an example of a radioligand used in the “radioligand displacement technique”
Raclopride
Why do typical antipsychotics not treat -ve symptoms, whereas atypical antipsychotics do?
Because typical neuroleptics non-selectively block DA Rs in all pathways, making potential PFC hypofunctioning (& resultant -ve symptoms) worse & causing side effects. In contrast, atypical antipsychotics which block D2 Rs less produce less extra-pyramidal (motor) side effects
Atypical antipsychotics may produce differences in the ___ of D2 R occupancy in the striatum vs. cortex which may…
Timing. Be responsible for reduced motor side-effects
Atypical antipsychotics additionally target…which may…
Serontonin functioning. Combat side effects
Define salience attribution
The process by which events & thoughts grab attention, drive action & influence goal-directed behaviour because of their association with reward or punishment
Prolonged use of ___ increases your risk of suffering from schizophrenia due to the impact of ___ on the dopamine system
Dopamine
Weinberger’s (1982) _ _ scans of Ss’ brains showed that the ___ ventricles were smaller than in controls
CT. Lateral
Steen’s meta-analysis reviewed studies investigating ___ ___ Ss’ whole brain volume, hippocampal volume & ventricular volume - why?
First episode. Because then the structural abnormalities found could be interpreted as causes rather than mere effects of the disorder
The seasonality of birth effect in S can be explained in terms of…
Materal influenza causing prenatal brain damage
It is said that prenatal brain damage remains silent until the patient’s 20s. Is this completely true?
No, Walker (1993/4) retrospectively analysed home videos of S patients when they were children. Relative to unaffected siblings, the to-be-S children displayed more -ve affect & poorer motor skills
Give 3 pieces of evidence against the early neurodevelopmental H1 on the lecture slides
1) Less than 1/3 of Sz show developmental abnormalities (e.g. poor motor skills, -ve affect, speech problems), 2) Most imaging studies are conducted post-onset & so could well reflect degeneration & 3) Programmed cell death (pruning) does not produce gliosis
Schizophrenics show a similar but more severe trajectory in cognitive impairments to sufferers of ___ ___ in terms of the relative severity of different symptoms. Deficits are found on…tasks
Bipolar disorder. Verbal, visual, abstraction, memory, executive-motor, perceptual-motor, mental control & vigilance tasks
It is possible that some schizophrenic symptoms e.g. cognitive symptoms are the result of other types of symptom. Is this supported by Mesholam-Gately’s (2009) meta-analysis into the cognitive impairments of Szs?
No, even first episode Sxs show cognitive symptoms & cognitive symptoms are not worse in chronic Sxs. However, this leaves open the possibility that the first episode of psychosis causes cognitive symptoms!
Give 3 findings which suggest that cognitive symptoms are core trait factors of S
1) They’re present early on in the disease’s course, 2) They do not just reflect lack of motivation or co-operation with lab tasks & 3) They remain present after recovery
Cognitive impairments likely reflect an endophenotype (hypofrontality) in patients. Their genetic origins are supported by their presence in…
Unaffected first degree relative of Szs who show impaired WM, set shifting & inhibition of prepotent responses
Why should cognitive symptoms be targeted by treatments?
Because they impair vocation & social functioning
What % of Sz patients experience AHs?
Over 60%
What is used to measure delusions in the normal population? Give some example statements with which one had to agree/ disagree
Peters Delusion Inventory (1996) which contains 40 items e.g. things in magazines were written especially for you, you are being persecuted in some way, you are destined to be someone very important
__ % of the normal population endorsed each delusional item. This % was higher for…
30%. Members of religious cults and psychotic patients
Peters (1999) found that new religious movement (NRM) members could not be…but could be differentiated from…
differentiated from deluded psychotic patients on 1) the no. of delusional items endorsed & 2) the level of conviction associated with each item. Christians & non-religious people
