Schizophrenia Spectrum Disorders

Question 1

Historical Context

Answer 1

Kraeplin (1986); described systematically- inappropriate behaviour, stereotypes motor behaviour, hallucinations
First person to conduct follow up studies of MI
Dementia praecox- early onset with deteriorating course & no recovery
Brueler (1926); coined the term schizophrenia
Disagreed that the condition was early onset & always had poor recovery
Schizo=split, phrenia= mind
Loosening of associations in thoughts or between emotions & thoughts

Question 2

Schizophrenia

Answer 2

Severe & enduring form of psychosis
Impaired insight & reoccuring & ongoing loss of contact with reality
Much variation between individual sufferers

Question 3

Psychosis

Answer 3

Loss of contact with reality
Disturbances in thought & language, sensory perception, emotion regulation, distortions in perception & reality which are different to those experienced by others around them
May lead to false beliefs & delusions about self & others

Question 4

Effects of psychosis

Answer 4

Social withdrawal
Preoccupation with personal world
Often difficult to maintain/obtain job
High incidence of homelessness; 11% average, rates higher in women, young people & chronically homeless, just under half not receiving treatment

Question 5

Liddle’s Tripatrite Model

Answer 5

Looks at which symptoms cluster together & then examine any underlying mechanism that contribute to these symptom clusters
Factor analysis of the signs & symptoms have identified 3 clusters
1) disorganised; speech, behaviour & flat or inappropriate mood
2) positive; hallucinations & delusions
3) negative; absence of activation, apathy, lack of motivation or poverty of speech
Each cluster may have different causes

Question 7

Positive symptoms

Answer 7

Hallucinations
Delusions
Disorganised speech
Disorganised or catatonic behaviour

Question 8

Negative symptoms

Answer 8

Flattened affect; lack of response to emotional stimuli
Poverty of speech
Apathy/avolition; lack of energy, lack of ability/interest in normal functioning
Cognitive dysfunction
Alogia; negative thought disorder (poverty of speech content & quality)
Anhedonia; inability to experience pleasure
Asociality; lack of social interaction

Question 9

Cognitive deficits

Answer 9

Often present before onset of psychotic symptoms
May have developmental role
Poor insight, impaired attentional process & memory deficits

Question 9

Disorganised symptoms

Answer 9

Disorganised speech

Bizarre behaviour; diverse forms, inappropriate affect

Question 10

Schneider’s first rank symptoms

Answer 10

Audible thoughts, voices arguing/discussing/commenting, somatic passivity experiences, thought withdrawal, influenced thought, thought broadcasting, delusional perceptions, all other experiences involving volition, impulses & effect
2nd rank symptoms; other disorders of perception, sudden delusional ideas, perplexity, depresssive & euthoric mood changes, feelings of emotional impoverishment

Question 11

Demographics

Answer 11

0.3-0.7% lifetime prevelance rate 
Most sufferers 15-35yrs
Among top 10 cases of disability worldwide 
Men & women both affected 
24 million sufferers worldwide 
Most sufferers require lifetime care

Question 12

Burden of schizophrenia

Answer 12

Life expectancy reduced by 15 yrs
Majority of premature mortality due to CHD
risk; smoking (70%), obesity (leading to diabetes), hypertension
About 1/20 commit suicide, usually near illness onset
Increased risk (10%) of alcohol problem or drug misuse
Burden on families & carers
Widespread stigma

Question 13

Cost & consequences of schizophrenia

Answer 13

Occupy more beds than any other psychiatric disorder
Rationalisation of resources introduces pressure to discharge patients into the community
Revolving door patients
Reinforcement of the negative stereotype of schizophrenia held by the general public

Question 14

Course of psychotic illness

Answer 14

Group 1 (22%); 1 episode only- no impairment 
Group 2 (35%); several episodes with no or minimal impairment 
Group 3 (8%); impairment after the first episode with subsequent exacerbation & no return to normally 
Group 4 (35%); impairment increasing with each of several episodes with no return to normality

Question 15

Delusions overview

Answer 15

Experienced by 75% of those hospitalised due to psychotic symptoms
Firmly held beliefs that usually involve a misinterpretation of perceptions or experiences & become fixed beliefs that are not amendable to change in light of contradictory evidence

Question 16

Types of delusion

Answer 16

Delusions of persecution
Delusions of grandeur
Delusions of reference; natural environmental event has special meaning
Bizarre delusions; first rank e.g. abduction
Delusional misidentification; imposters
Delusions of guilt or worthlessness
Nihilistic delusions; belief that self, body, part of, other person or world doesn’t exist
Erotomanic delusions; another person, often important or famous, is in love with them

Question 17

Delusions of control

Answer 17

Thought insertation; have to distinguish from auditory hallucinations
Thought withdrawal: thoughts taken from you
Thought broadcasting; belief that others can here thoughts
Thought block; sudden loss of train of thought

Question 20

Hallucinations

Answer 20

False sensory experiences
Differentiate between illusions
Auditory hallucinations most common (70% experience it)
Associated with earlier age of onset

Question 21

Auditory hallucinations

Answer 21

Vary
Running commentary, 1st/2nd person voice, group, discussing individual in critical way
Perceived as external but over time come to have insight of origin
When experienced there is neural activity in brain regions involved in speech generation & sound perception
Reality-monitoring effect; difficulties in distinguishing whether something is real or imagined

Question 22

Brebion et al (2000)

Answer 22

Schz vs controls
Asked to remember list of self-generated or experimenter generated words
Scz more likely to list false positives
More likely to say that self-generated words were experimenter generated

Question 23

Motor systems

Answer 23

Catalonia; severe motor abnormalities
Catatonic stupor (freezing in awkward poses)
Excitement (over-activity)
Stereotyped movements (rocking, rubbing)
Waxy flexibility (awkward positions maintained)

Question 24

Disorganised thinking (speech)

Answer 24

Derailment/tabgeniality; sentence goes off course, unrelated topics
Word salad; unintelligible random mixture of words & phrases
Neologisms; percuiliar combinations of words or a word coined by a psychotic which is meaningless except to the coiner
Clanging/clang associations; words chosen for their sound rather than meaning
Poverty of content of speech; lack of additional, unprompted content seen in normal speech

Question 25

Schizophrenia spectrum disorders

Answer 25

Spectrum based on a gradient of psychopathology & impairment
4 main disorders; delusional disorders, brief psychotic disorder, schizophrenia, schizoaffective disorders

Question 26

Delusional disorder

Answer 26

One or more delusions lasting at least 1 month
Normal functioning not markedly impaired, behaviour not bizarre
Any manic or depressive episode has been brief in relation to delusional episode
Disorder is not directly attributable to use of substance or medication

Question 27

Brief psychotic disorder

Answer 27

Sudden onset of at least one of the main psychotic symptoms Change has to occur within 2 weeks Associates with emotional turmoil & overwhelming confusion

Question 28

Schizophrenia

Answer 28

At least 2 must be present; delusions, hallucinations, disorganised speech, highly disorganised or catatonic behaviour, negative symptoms Ability to function in 1 or more major areas e.g. work markedly diminished Continuous signs of disturbance for at least 6 months

Question 29

Schizoaffective disorder

Answer 29

Presence of significant mood episode alongside psychotic symptoms Delusions or hallucinations for 2 or more weeks without occurance of major mood episode

Question 30

DSM-5

Answer 30

Raises symptom threshold; individual muse exhibits at least 2 specified symptoms No special attribution of bizarre delusions or 1st rank auditory hallucinations (2 or more voices conversing) due to poor reliability No longer identify subtypes of schizophrenia; dimensional scale provided instead

Question 31

Psychosis spectrum

Answer 31

Schizotypy; continuum of personality characteristics Schizophreniform disorder; time dependent diagnosis Attenuated psychotic symptoms syndrome; psychosis risk syndrome, mild psychotic symptoms, poor diagnostic reliability Psychosis proneness can be used to investigate presence of sub-clinical levels of psychotic symptoms

Question 32

Schizotypal personality

Answer 32

Dimensional model of schizophrenia Found with cluster A personality disorders; odd or ecentric Pervasive pattern of social & interpersonal deficits marked by acute discomfort with reduced capacity for close relationships, cognitive or perceptual distortions & eccentricities Superordinate factors of traits are -ve,+ve or disorganised Subordinate factors are; ideas of reference/suspiciousness, odd or ecentric behaviour, constructed affect/no close friends, odd speech, excessive social anxiety, unusual perceptual disturbances, odd beliefs/magical thinking

Question 33

Psychotic symptoms in the general population

Answer 33

Bentall (2007); firmly opposed to the biomedical model Argues that no clear distinction exists between those diagnosed with mental illnesses & the well Insists that schizotyoal existences are common Rufus May; heading voices network

Question 34

The divided self; an existential study in sanity & madness

Answer 34

Aimed to make madness comprehensible Revolutionised the way we perceive mental illness Using case studies of patients he’d worked with, Dr Laing argues that psychosis is not a medical condition but an outcome of the divided self or the tension between the 2 personas with ya (private & public)

Question 35

The dangerous patient

Answer 35

Walsh at al (2002); violence & schizophrenia, examining the evidence People with a diagnosis of schizophrenia are more likely than other members of the general pop to be violent But proportion attributable to scz is small (<10%) Co morbid substance abuse considerably increases the risk Violence as a result of delusional beliefs is a common cause

Question 36

Stress-diathesis model of causation in psychosis

Answer 36

Effects of stress on cortisol production may be mediating factor Stressors; early parental factors, dysfunctional family relationships, inability to cope during adolescence

Question 37

Genetic risk/prevelance

Answer 37

``` MZ twins; 48% DZ twins; 17% Siblings; 9% Parents & half siblings; 6% General pop; 1% ```

Question 38

Genes for schizophrenia overview

Answer 38

Not one gene; does not follow Mendelian pattern of inheritance

Question 39

DRD2 susceptibility gene

Answer 39

DRD2; altered D2 receptor available in areas with dopaminergic activity (striatum & cortisol regions) SNP Rs6277; genetic variation resulting in altered risk of developing schizophrenia Effects of genotypic variation may affect cognition; working memory, attentional processes & response inhibition

Question 40

COMT susceptibility gene

Answer 40

COMT; regulation of dopamine metabolism at synapses | COMT Val158Met; associated with cognitive dysfunction in schizophrenia

Question 41

Dopamine hypothesis

Answer 41

Antipsychotic drugs like chlorpromazine block DA receptors (D2); long term usage can cause parkinsons type symptoms Amphetamine psychosis resembles schizophrenia: blocks DA transporters, exacerbates symptoms May give added salience to cognitions (positive symptoms)

Question 42

Dopamine pathways

Answer 42

Pathway to prefrontal cortex leads to more negative symptoms Pathway to nucleus accumbens leads to more negative symptoms

Question 43

Evidence to support the DA hypothesis

Answer 43

Antipsychotic drugs most effective in treating schizophrenia & dopamine antagonists Side effects of antipsychotic drugs are similar to those seen in Parkinson’s The drug L-dopa produces schizophrenia like symptoms in some people Amphetamines can make psychotic symptoms worse in some schizophrenics

Question 44

Evidence against the DA hypothesis

Answer 44

Many people with schizophrenia are not helped by DA antagonists Symptoms subside a lot slower than would be expected if the disorder were just a neurotransmitter imbalance Negative symptoms are not wholly treated by antipsychotics

Question 45

Role of other neurotransmitters

Answer 45

Several psychotomimetic drugs (induce psychosis like experience) exist which act on other neurotransmitter symptoms LSD & psilocybin act on 5HT, 5HT1 or 2a receptor agonists, newer antipsychotics act to block 5HT as well as DA ketamine & PCP act as glutamate antagonists; glutamate is increased in frontal cortex, hippocampus & amygdala, best drug model of certain-psychotic-like experiences

Question 46

Neuroanatomical changes in schizophrenia

Answer 46

26% increase in ventricle size Decrease in grey matter; specific areas affected more than others (hippocampus, PFC, anterior cingulate cortex, insular cortex, white matter)

Question 47

Neurodevelopmental model

Answer 47

Genes involved in neurodevelopment and/or environmental insults in early life lead to aberrant brain development, which in turn predisposes to the later onset of psychosis Dominant paradigm guiding research 80’s Schizophrenia result of abnormal brain development, secondary to genetic predisposition & early environmental factors Ventricular enlargements don’t change, altered cytoarchitrcture & absence of gliosis all led to neurodevelopmental theory over neurodegenarative

Question 48

Developmental risk factor model

Answer 48

Early causes; genetic, obstretric complications Childhood vulnerability Late causes (adolescence); life events, drug abuse Dysplastic networks, cognitive impairment & social difficulties Eventually psychosis

Question 49

Environmental risk factors

Answer 49

Place/time of birth; winter, urban Infection; flu, respiratory, rubella (high risk), poliovirus, CNS Prenatal; famine, bereavement (high risk), flood, unwantedness, maternal deprivation Obstetric: Rh incompatibility, hyproxia, CNS damage (v high risk), low birth weight, pre-eclampsia

Question 50

Psychosocial factors

Answer 50

Urban poor more at risk Culture Increased stress in lower SES pop Social isolation Migration Socio-genic hypothesis; environmental causality Socio-selection theory; person selects environment Thought & communication styles in families Schizophrenigenic mothers; the way they communicate may lead to child’s psychosis High expressed emotion in family; more likely to be sciziohrenic (criticism & hostility), particularly concealing, controlling & denying meaning

Question 51

Gene x environment interactions

Answer 51

Occur when the effect of exposure to an environmental pathogen on health is conditional of a persons genotype (pathogenesis model) First evidence that genotype moderates the capacity of an environmental risk factor to bring about mental health problems reported in 2002: role of genotype in cycle of violence in maltreated children

Question 52

COMT genotype & cannabis use in early adolescence

Answer 52

Increases risk of developing psychosis & schizotypy

Question 53

Sub-clinical features in development

Answer 53

``` Delayed motor milestones Speech defects, solitary Cognitive decrement Social anxiety Eventually schizophrenia ```

Question 54

Cognitive domains affected in psychosis (willed action & working memory)

Answer 54

Willed action; diminished capacity to regulate willed (goal-directed) & stimulus-driven action systems Working memory; studies of animals & of cognitive function in normal, brain-injured & schizophrenic subjects support the theory that a defect in working memory (ability to guide behaviour by representations) may be fundamental impairment leading to schizophrenic thought disorder

Question 55

Cognitive domains affected in psychosis (cognitive dysmetria & deficits & biases)

Answer 55

Cognitive dysmetria; a disruption in neuronal circuitry produces difficulty in prioritising, processing, coordinating & responding to info, can account for broad diversity of scz symptoms Deficits & biases; attentional processes (over/under attention) can lead to attribution am & interpersonal biases (external attributes, cognitions of persecution), deficits in their of mind & link to paranoia

Question 56

Reasoning bias & delusion formation

Answer 56

RB; jumping to conclusions, over-adjustment of probability estimates following a single instance of disconformity evidence Seen in people at risk of schizophrenia as well

Question 57

Threat-anticipation model of persecutory delusions

Answer 57

4 factors important in development of cognitive biases involved in persecutory delusions 1) anomalous experiences that do not have an obvious explanation e.g. hallucinations 2) anxiety, depression & worry may cause a bias towards negative thinking & threatening interpretation of events 3) reasoning biases leading to jumping to conclusions rather than questioning 4) social factors such as isolation & trauma

Question 58

Psychology of alien abduction; McNally et al (2012)

Answer 58

Traits associated with identifying as an alien abductee; Experiencing sleep paralysis & hallucinations when waking Tendency to recall false memories High levels of absorption New age beliefs Familiarity with cultural narrative of alien abduction

Question 59

Interpretational bias

Answer 59

13% of individuals hear voices In psychosis, there is a bias towards interpreting voices as threatening, can lead to increased voice hearing Failure in signal detection leads to interpretational bias Increasing externalisation & controllability leads to increased developing of relationship with the voice(s)

Question 60

Psychodynamic model of psychosis

Answer 60

Caused by regression to a previous ego state of primary narcissism Results in loss of contact with reality Due to cold & unnurturing parents

Question 61

Behavioural model of psychosis

Answer 61

Role of learning & conditioning Bizzare behaviours may arise due to operant conditioning May be due to difficulty attending to appropriate social cues

Question 62

Evolutionary model of schizophrenia

Answer 62

Consequence of the evolution of language Scz individuals have less left-sided dominance for language Scz associated with atypical patterns of lateralisation Purported to explain more severe form of psychosis seen in makes who have increased lateralisation

Question 63

The role of dopamine

Answer 63

One if it’s roles is to mediate the salience if environmental events & internal representations Dysregulated hyperdopaminergic state may lead to abberant assignment of salience to elements of ones experiences Psychosis as a state of aberrant (non-normal) salience Aims to link the biology, phenomenology & pharmacology in scz into a unitary framework