Chapter 8 (Davey) - Experiencing Psychosis: Schizophrenia Spectrum Porblems

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Downward drift

Downward drift

individuals exhibiting psychotic symptoms fall to the bottom of the social ladder or become homeless, because they can not hold down a job or sustain relationships

Psychosis

a collective name for an extensive range of disparate symptoms that can often leave an individual feeling frightened and confused

→ The presence of different combinations of these symptoms may lead to a diagnosis of a schizophrenia spectrum disorder

Schizophrenia spectrum disorder

Separate psychotic disorders that range across a spectrum depending on severity, duration and complexity of symptoms

Main diagnostic categories

• schizophrenia

• schizotypal personality disorder

• delusional disorder

• brief psychotic disorder

• schizoaffective disorder

Key cognitive and behavioural features that define psychosis

• delusion

• hallucinations

• disorganized thinking

• abnormal motor behaviour

• negative symptoms (indicative of diminished emotional expression)

Dementia Praecox (Emil Kraepelin, 1896)

an early, general term for a number of diagnostic concepts including paranoia, catatonia and hebephrenia

→ Viewed as a single disease that manifests in adolescence or early adulthood, no recovery possible

Catatonia

abnormality of movement and behaviour which may involve repetitive or purposeless overactivity, resistance to passive movement, and negativism

Hebephrenia

symptoms indicative of incoherence and fragmentation of personality

Eugen Bleuler (1908)

believed that the onset of dementia praecox was not restricted to adolescence and early adulthood and that it doesn’t inevitably lead to dementia, he preferred the term schizophrenia

Positive psychotic symptoms

characteristics of psychotic symptoms which tend to reflect an excess or distortion of normal functions

Negative psychotic symptoms

symptoms characterized of a diminution or loss of normal functions

(DSM-5 lists four positive and one negative symptom for schizophrenia spectrum disorder)

Delusions

firmly held but erroneous believes that usually involve a misinterpretation of perceptions or experiences and become fixed beliefs that are not amenable to change (e.g. believing that the internal organs have been taken out and replaced by someone else’s)

Persecutory delusions (paranoia)

the individual believes they are being persecuted, spied upon, or in danger (usually as a result of a conspiracy of some kind)

Grandiose delusions

the individual believes that they are someone with fame or power or have exceptional abilities, wealth or fame (e.g. being Jesus)

Delusions of control

the individual believes that their thoughts, feelings or actions are being controlled by external forces (e.g. extraterrestrial or supernatural beings)

Nihilistic delusions

the individual believes that some aspect of either themselves or the world has ceased to exist (e.g. believing to be dead)

Erotomanic delusions

relatively rare, the individual believes that a person of higher social status falls in love and makes amorous advances towards them

• as a result of this, sufferers often stalk their target

Individuals with erotomanic delusions

• Usually, isolated loners without a partner or full-time occupation

• Around half have a first-degree relative with a delusional disorder

• Many develop fantasies in which they are driven to protect, help or harm their victim

2 types of erotomanic delusion

• Believing, to have a relationship with the victim

• Believing to be destined to be with the victim, even though they may have never met them

Hallucinations

a sensory experience in which a person can see, hear, smell, taste or feel something that isn’t there

• Auditory hallucinations are most common (around 70% of sufferers)

• Visual hallucinations are the second most common type

• While some sufferers are convinced what they perceive is real, others are aware that it might not be reel

Reality-monitoring deficit

having problems with distinguishing between what occurred and what did not

Self-monitoring deficit

being unable to distinguish between thoughts and ideas generated by oneself and those of others

Derailment

a disorder of speech where the individual may drift quickly from one topic to another during a conversation

Loose association

disorganized thinking in which the individual may drift quickly from one topic to another during a conversation

Tangentiality

(disorganised thinking)

a disorder of speech in which answers to questions may be tangential rather than relevant

Clanging

A form of speech pattern in schizophrenia where thinking is driven by word sounds.

→For example, rhyming or alliteration may lead to the appearance of logical connections where non in fact exists

Neologisms

Made up words, frequently constructed by condensing or combining several words

Word salads

when the language of the person experiencing a psychotic episode appears so disorganized that there seems to be no link between one phrase and the next

Sufferers of disorganised thinking have:

• difficulty inhibiting associations between thoughts

• difficulties understanding the full context of a conversation

→ Poverty of content

Poverty of content

a characteristic of the conversation of individuals suffering psychosis in which their conversation has very little substantive content

Grossly Disorganized or Abnormal Motor Behaviour

• Behaviour may be childlike and silly, inappropriate to the context, unpredictable and agitated (e.g. shouting in the streets)

• The individual may have difficulty completing any goal-directed activity (e.g. cooking, maintaining personal hygiene)

• The appearance may be disheveled and they may dress inappropriately (e.g. underwear in public or thick clothes in warm weather)

Catatonic stupor

decrease in reactivity to the environment

Catatonic rigidly

maintaining rigid, immobile postures for many hours

Waxy flexibility

remaining in a posture into which one has been placed by someone else

Catatonic negativism

resisting attempts to be movement

Catatonic excitement or stereotype

purposeless and excessive motor activity

Diminished emotional expression

a reduction in facial expressions of emotion, lack of eye contact, poor voice intonation, and lack of head and hand movements that would normally give rise to emotional expressions

Affective flattering

limited range and intensity of emotional expression

Avolition

an inability to carry out or complete normal day-to-day goal-oriented activities → the individual shows little interest in social or work activities

Alogia

a lack of verbal fluency in which the individual gives very brief, empty replies to questions

Anhedonia

the inability to react to pleasurable or enjoyable events

Asociality

a lack of interest in social interactions, perhaps because of a gradual withdrawal from social interactions generally

Brief psychotic disorder

The sudden onset of at least one of the main psychotic symptoms, with this change from a non-psychotic state of the appearance of symptoms occurring within 2 weeks and being associated with emotional turmoil or overwhelming confusion

Schizophrenia

the five central characteristics are delusions, hallucinations, disorganized speech, grossly disorganized and catatonic behaviour, and flattened affect, poverty of speech and apathy

→ Lifetime prevalence: 0.3-0.7%

Schizoaffective disorder

characterized by schizophrenia symptoms plus a period reflecting either depression or mania

• Frequently impairs occupational functioning

• May be associated with restricted social functioning, difficulties with self-care, and an increased risk for suicide

3 stages of the course of psychotic symptoms

1. Prodromal stage

2. Active stage

3. Residual stage

1. Prodromal stage

the slow deterioration from normal functioning to the delusional and dysfunctional thinking characteristic of many forms of schizophrenia, normally taking place over an average of 5 years

• First signs of psychotic symptoms usually onset during late adolescence or early adulthood (51% between 15-25 years, over 80% between 15-35 years)

• This stage is first exhibited as slow withdrawal from normal life and social interaction, shallow and inappropriate emotions, and deterioration in personal care and work or school performance

Diathesis-stress model

the perspective that psychopathology is caused by a combination of a genetically inherited biological diathesis (a biological predisposition) AND environmental stressors

Harrop & Tower

argue that prodromal-like signs in normal adolescence appear to be linked to normal development, and that psychotic symptoms may emerge from a troubled teenage state that has failed to cope with normal maturation

Attenuated psychotic symptom syndrome

characterized by mild symptoms of psychosis that don`t meet the diagnostic criteria for full-blown schizophrenia

2. Active stage

an individual begins to show unambiguous symptoms of psychosis, including delusions, hallucinations, disordered speech and communication, and a range of full-blown symptoms

3. Residual stage

the individual ceases to show prominent signs of positive symptoms (e.g. delusions, hallucinations or disordered speech)

• Around 28% of sufferers remit after one or more active stage, 22% will continue to show positive symptoms over the long term, around 50% will alternate between active and residual stages

• Relapse can often be traced to either stressful life events or return to a stressful family environment, or non-adherence to medication (40-50% fail at some point to adhere to their medication)

Complaint-orientated approach

argues that there is a need to study individual symptoms (because of the range of diverse symptoms), and that individual symptoms may have their origin is psychological mechanisms that underlie normal experience

Sociocultural views of psychosis

the course of psychotic symptoms may be determined by the simple act of diagnosing someone with schizophrenia or by the fact that they are born into a disadvantaged socio-economic group

→ this may be enough to promote the development of psychotic symptoms

Genetic factors (aetiology schizophrenia)

heritability estimate is approximately 80%

→ additionally: support for the diathesis-stress model

Molecular linkage analysis

blood samples are collected in order to study the inheritance patterns within families that have members diagnosed with schizophrenia

Genome-wide association studies (GWAS)

technique which allows researchers to identify rare mutations in genes that might give rise to psychopathology symptoms, especially those duplication)

Smooth-pursuit eye tracking

the ability to follow a moving object in a smooth continuous movement with your eyes while keeping your head still

• Many individuals with a diagnosis of schizophrenia are unable to do this (30-45% of first-degree relatives of individuals diagnosed with schizophrenia exhibit poor performance, even when not diagnosed with schizophrenia)

• Smooth-pursuit eye tracking can be used as a genetic marker for schizophrenia

Dopamine hypothesis

a biochemical theory which argues that the symptoms of schizophrenia are related to excess activity of the neurotransmitter dopamine

Phenothiazines

drugs that help to alleviate the symptoms of psychosis by blocking the brain’s dopamine receptor sites and so reduce dopamine activity

Amphetamine psychosis

a syndrome in which high doses of amphetamines taken for a long period of time produce behavioural symptoms in humans and animals that closely resemble symptoms of psychosis (e.g. paranoia)

→ Amphetamines produce these disturbed behaviour patterns by increasing dopamine activity in the brain

Two important dopamine pathways in the brain

mesolimbic & mesocortical pathway

• Both pathways begin in the ventral tegmental area of the brain

The neuroscience of schizophrenia

Individuals with schizophrenia show structural differences in the brain, which develop throughout the lifetime and are usually apparent at the time of the first psychotic episode → suggests that they play a causal role rather than being a consequence

• Their brain tends to be smaller

• Associated with enlarged ventricles → overall reduction in cortical grey matter

• Abnormalities in the temporal cortex, including limbic structures, and basal ganglia and the cerebellum

Ventricles

areas in the brain containing cerebrospinal fluid

Basal ganglia

a series of structures located deep in the brain responsible for motor movement

Cerebellum

the part of the brain at the back of the skull that coordinates muscular activity

(schizophrenia) Abnormalities in the lobe-limbic system are more associated with

the positive symptoms

(schizophrenia) Auditory hallucinations are associated with

neural activation in the temporal lobes-limbic system

What causes these structural and functional differences?

• Genetic mutations in genes

• Prenatal factors

• Environmental factors

→ Psychotic symptoms are often developed during adolescence because the prefrontal cortex is a brain structure that only fully matures in adolescence, so any deficits are likely to manifest in an obvious way at maturation

Viral Infections and Psychotic Symptoms

Hypothesis: psychotic symptoms may be triggered by viral infections experienced either prenatally or postnatally

Primary narcissism (Freud)

psychosis is caused by regression to a previous state which gives rise to a preoccupation with the self, which is characteristic of the oral stage of development

→ Thought to be caused by unnurturing parents

Schizophrenogenic mother (Fromm-Reichmann, 1948)

a cold, rejecting, distant and dominating mother who causes schizophrenia

• They demand dependency and emotional expressions from their children, but reject displays of affection and criticize the dependency they attempted to foster  due to such conflicting messages the child withdraws and loses touch with reality

Behavioural theories

views that suggest a role for learning and conditioning in the development of psychotic symptoms

• Studies have shown that inappropriate behaviours can be eliminated and acceptable behaviours developed using operant reinforcement procedures → this suggests that at least some of the unusual behaviours exhibited by individuals with schizophrenia may be under the control of contingencies of reinforcement

Ullman & Krasner (1975)

argued that bizarre behaviours by individuals with schizophrenia are rewarded by a process of operant reinforcement, because bizarre behaviour gets more and more attention and is therefore strengthened

Orienting response

a physiological reaction to a stimulus consisting of changes in skin conductance, brain activity, heart rate and blood pressure, that naturally occurs when one is presented with a prominent stimulus

• Around 50% of individuals with schizophrenia show abnormalities in their orienting response, suggesting that they are not processing such stimuli

Overattention

when an individual attends to all aspects of their environment and is unable to filter out unimportant stimuli

• Those with schizophrenia are highly distractable and perform poorly on cognitive tasks when also presented with unimportant stimuli BUT they perform better than non-diagnosed participants at tasks where attending to distracting stimuli can improve performance

Negative priming effect

non-clinical participants show an increased reaction time when asked to name a target word they have previously been asked to ignore

• those diagnosed with schizophrenia fail to exhibit this negative priming effect

Paranoid schizophrenia

a sub-type of schizophrenia characterized by the presence of delusions and persecution

Attentional bias

Individuals with delusional disorder selectively attend to pathology congruent information (e.g. those with persecutory delusions exhibit attentional bias towards stimuli that have emotional meaning or are paranoia relevant)

Attributional biases

• Individuals with delusional disorder (especially persecutory delusions) have a bias towards attributing negative life events to external causes and positive events to internal causes, but only when there was a perceived threat to the self

• It will also act to maintain paranoid beliefs, and maintain delusions that someone or something is threatening them

Jumping to conclusions

a form of reasoning bias in which the process of making a decision about the meaning or importance of an event on the basis of insufficient evidence

→ It is thought thatthis may create a biased reasoning process that leads to the formation and acceptance of delusional beliefs and eventually to delusional symptoms

‘Jumping to conclusions’ task

participants view two jars, one with 85 red and 15 yellow beads and one with 85 yellow and 15 red beads, then the jars are hidden from them and a series of beads is drawn one by one from ONE jar, the participant is asked to say which jar the beads are drawn from, the fewer the number of beads draw before the participant made a decision, the greater the jumping to conclusions bias

Threat-anticipation model of persecutory delusions

four factors are important in contributing to the development of cognitive biases

1. Anomalous experiences such as hallucinations that do not have a simple or obvious explanation and are therefore open to biased interpretations

2. Anxiety, depression and worry that would normally create a bias towards negative thinking and threatening interpretations to events

3. Reasoning bias on the part of the individual which leads them to seek confirmatory evidence for their persecutory interpretations rather than question them (e.g. jumping to conclusions)

4. Social factors, such as isolation and trauma, which add to feelings of threat, anxiety and suspicion

Interpretational bias

Many individuals with schizophrenia have a bias towards interpreting cognitive intrusions such as hearing voices as threatening

→ in this case a perfectly normal auditory hallucination may be interpreted as threatening which causes anxiety, negative mood and physiological arousal which produces more auditory hallucinations