What is the Role of Affect in - PowerPoint PPT Presentation

1 / 37
About This Presentation
Title:

What is the Role of Affect in

Description:

False, based on incorrect inference about external reality. ... and despite what constitutes incontrovertible and obvious proof or evidence to the contrary ... – PowerPoint PPT presentation

Number of Views:26
Avg rating:3.0/5.0
Slides: 38
Provided by: A108
Category:

less

Transcript and Presenter's Notes

Title: What is the Role of Affect in


1
What is the Role of Affect in
Delusion Formation ?
Vaughan Bell School of Psychology, Cardiff
University
Hadyn Ellis, Peter Halligan
2
Outline
  • Defining issues and phenomenology
  • Affect and delusions Prevalence and
    co-occurrence
  • Affect and delusions, theoretical approaches
  • Defence models of delusion
  • Direct models
  • Metacognitive role for affect ?
  • Neuropsychological correlates

3
What is a Delusion ?
  • The DSM defines a delusion as a belief that is
  • False, based on incorrect inference about
    external reality.
  • Firmly sustained, despite what almost everybody
    else believes...
  • and despite what constitutes incontrovertible
    and obvious proof or evidence to the contrary
  • The belief is not one ordinarily accepted by
    other members of the person's culture or
    subculture.

4
What is a Delusion ?
  • Every criterion of this definition has been
    criticised (Spitzer, 1990 Bell, Halligan
    Ellis, 2003)
  • Including the assumption that delusions are
    beliefs (famously by Berrios, 1991)
  • But despite these defining issues there is
    clearly something to explain

5
Case 1
A 22-year-old woman had the delusion that
thoughts and feelings emanating from her mothers
unconscious were being carried in raindrops that
fell on her air conditioner. When the raindrops
hit the air conditioner they made a noise, and
simultaneously these thoughts and feelings merged
with her own unconscious. This merging had
resulted in her own mental illness.
6
Case 2
AQ, a 36 year old woman with a previous diagnosis
of bipolar affective disorder was admitted to
hospital concerned that she was being tracked by
cameras that had been placed around her house,
that were transmitting images of her across
radio, television and the internet. AQ had also
experienced beams of light coming into her
house which she believed were being controlled
via the internet and were involved in her
surveillance. After admission to the hospital
ward, she voiced concerns about being watched by
beams of light and was suspicious of the electric
lights in her room. AQ was subsequently diagnosed
as having a manic episode with psychotic symptoms.
7
Affective Disturbance in Delusions
  • Often difficult to pin-down as cross-sectional
    studies often group participants using concepts
    like psychosis or schizophrenia, rather than
    delusions per se.
  • However, despite these drawbacks, it is obvious
    there is a clear link between delusions and
    emotion.

8
Co-occurrence and Prevalence
  • Bowman and Raymond (1931) 58 of admissions with
    manic-depressive psychoses had delusions.

9
Disturbed Affect in Psychosis
  • Experience sample of delusional patients
  • Myin-Germeys et al (2001) intensity of delusion
    was associated with lower negative affect.
  • Psychotic outpatients
  • Steer et al (2003) 18 were severely anxious on
    the Beck Anxiety Inventory.
  • Prodrome of paranoid schizophrenia
  • Gourzis et al (2002) depressed mood (10),
    anxiety (22) and anger (48) in prodrome (x
    14.6 months).

10
Delusions in Mood Disorder
  • General population survey
  • Ohayon and Schatzberg (2002) 10.7 with feelings
    of worthlessness or guilt had delusions.
  • Depressed patients
  • Cassano et al (2004) total manic items endorsed
    by unipolar patients predicted delusional
    ideation.
  • Delusional depression
  • Seretti et al (2000) treating the mood disorder
    without antipsychotics reduces delusions.

11
Defence Models of Delusion
  • One of the first was from Freud (1911) who
    analysed Schrebers Memoirs of my Nervous
    Illness.
  • Freud argued that delusions resulted from the
    sublimation of homosexual desire.
  • Unsurprisingly, psychological theory has since
    moved on, although the psychoanalytic angle is
    not dead.
  • Adler (1914) argued that paranoia occurs due to
    blaming others, to mask an inferiority-complex.

12
Bentalls Attributional Model
  • Like Adler, Bentall (1994) argued that
    persecutory delusions are an extreme self-serving
    attribution bias (see Mezulis et al, 2004).
  • The result of trying to prevent low self-esteem
    thoughts entering consciousness by making
    excessive external-personal attributions for
    negative events.
  • This has now been reformulated (Bentall et al,
    2001) to include mood effects of actual-self /
    ideal self discrepancies.
  • And relies on the distinction between explicit
    and implicit self-esteem.

13
Events
Attribution / Self-representation 1
Positive
Negative
Internal bias
High
Ideal-self comparison
Self-esteem / mood
Internal bias
Low
Search self representations
Benign external situational
Stored self-knowledge
Attribution
Internal
External personal
Beliefs about others (inc paranoia)
14
Events
Attribution / Self-representation 2
Positive
Negative
Internal bias
High
Ideal-self comparison
Self-esteem / mood
Internal bias
Low
Search self representations
Benign external situational
Stored self-knowledge
Attribution
Internal
External personal
Beliefs about others (inc paranoia)
15
Events
Attribution / Self-representation 3
Positive
Negative
Internal bias
High
Ideal-self comparison
Self-esteem / mood
Internal bias
Low
Search self representations
Benign external situational
Stored self-knowledge
Attribution
Internal
External personal
Beliefs about others (inc paranoia)
16
Criticisms of Bentalls Model
  • Largely, the poorly defined concept of
    self-esteem, which has probably led to equivocal
    findings in patient with persecutory delusions
  • They have included
  • High self-esteem (Candido and Romney, 1990)
  • High self / ideal-self discrepancy (Kinderman and
    Bentall, 1996)
  • Low self-esteem (Freeman et al, 1998)

17
Mahers One Stage Model
  • Maher (1988/99) has argued that delusions arise
    from normal reasoning applied to anomalous
    experience.
  • Anomalous experience.
  • Causing an arousal of anxiety, tension or fear.
  • Explanation of experience by normal reasoning.
  • Reduction in anxiety.
  • Persistence of explanation to defend against
    further anxiety.

18
Jonathan Miller video clip
19
Intolerance of Ambiguity
  • Studies have shown that intolerance to ambiguity
    is associate with delusional ideation.
  • For example in
  • Delusional people with paranoid schizophrenia
    (McReynolds et al, 1964)
  • People with persecutory delusions (Bentall and
    Swarbrick, 2003)
  • People high in delusional ideation (Colbert and
    Peters, 2002)

20
Direct Models
  • These argue that emotion directly influence the
    formation and maintenance of delusions.
  • Rather than delusions being a response to
    unpleasant emotion (defence), or
  • being emotion being the result of a delusional
    belief (consequence).

21
Institute of Psychiatry Model
  • For non-affective psychoses the following is
    proposed (recent summary in Freeman and Garety,
    2004)
  • Hemsley (1994) - memories of input regularities
    influence current perception.
  • These influences are weakened as per the
    stress-vulnerability model.
  • This disrupts assessment of the significance of
    incoming stimuli, causing novel or unexpected
    stimuli to enter consciousness.
  • The mismatch between predictions of the world and
    perception causes arousal.

22
Institute of Psychiatry Model
  • Similarly Gray (1982) Behavioural Inhibition
    Model, proposes that unexpected stimuli causes
  • BI, arousal, increased attention to environment.
  • Depending on appraisal this might be experienced
    as anxiety or pleasurable arousal.
  • Garety and Hemsley (1994) - this might affect
    information processing, e.g. inferential
    reasoning biases in delusional patients.
  • Further delusional explanation may arise from the
    attempt to explain the seemingly unexplained
    arousal.

23
Shared Themes
  • For affective psychoses, Freeman and Garety
    (2003, 2004) note the similarity in themes
    between certain emotions and delusions

Adapted from Freeman and Garety (2003)
24
Shared Themes Criticisms
  • Connections between delusions and emotions (and
    vice versa) seem underdetermined and simplistic.
  • Some delusions seem not to have a reliable
    emotion (e.g. religious, lycanthropic).
  • Freeman and Garety dismiss religious delusions as
    being secondary elaborations of emotional states.
  • They appear to be specific explanations that
    draw on pre-existing beliefs concerning religion
  • Despite the fact that a delusional must not be
    an article of religious faith, i.e. not
    established dogma
  • Also sensed presence (Cook and Persinger, 1997)

25
Shared Themes Criticisms
  • Mono-delusional conditions (e.g. Cotard delusion)
    have also been cited as difficult to assimilate
    into this framework.
  • Standard explanation
  • Person is depressed, perceptual input loses
    meaning due to lack of emotional modulation, lack
    of meaning leads person to believe they are dead.
  • Klee (2004) has argued that the emotion may not
    necessarily be that specific.
  • Why dead ? And not that they are, for example,
    made out of clay ?

26
Direct Models of Normal Belief
  • But Frijda et al (2000) have noted that
  • Emotions can awaken, intrude into, and shape
    beliefs, by creating them, by amplifying or
    altering them, and by making them resistant to
    change
  • Clore and Gasper (2000) have noted a number of
    ways this may happen with normal belief.
  • Emotion as attention (selective attention bias)
  • Intensity and goal focus (positive feedback loop)
  • Emotion as information (feelings as evidence)

27
Clore and Gasper (2000)
Belief / attention / information cycle.
Directs
Modifies
Information sampling
Attention
Guides
28
Affective Bias and Delusion
  • Good evidence that affect based attention /
    reasoning biases are increased in delusional
    patients compared to psychiatric /
    non-psychiatric controls, e.g
  • Emotional stroop (Bentall and Kaney, 1989)
  • Threat word recall (Bentall et al, 1995)
  • Conditionals and syllogisms (Kemp et al, 1997)
  • Inferential reasoning (Dudley et al, 1997
    although see Young and Bentall, 1997)
  • Threat perception / visual scan-paths (Phillips
    et al, 2000)

29
Clore and Gasper (2000)
Attentional funnelling effect of emotion.



30
Goal Focus
  • For example Freeman et al (2000) found a high
    prevalence (100) of safety behaviours in people
    with persecutory delusions.
  • As well as the well known bias for confirmatory
    evidence
  • ...there seems to be a bias to avoid
    disconfirmatory evidence as well.
  • Delusional people avoid situations which would
    disconfirm their delusions.

31
Feelings as Evidence
  • Capgras delusion is a delusional belief that
    (usually) close relatives have been replaced by
    identical looking impostors.
  • Ellis et al (1997) showed that Capgras patients
    show a reduced automatic response to familiar
    faces.
  • i.e. they have a distorted feeling of knowing
    (Bruce and Young, 1986) for faces.
  • Perhaps in a similar way to Damasios (1998)
    controversial somatic marker hypothesis.
  • Or, some other form of metacognitive process

32
Affect as Metacognition ?
  • Might feeling of knowing / familiarity share
    processing or resources with aspects of affect ?
  • Nelson (1999) defines metacognition in terms of
  • Monitoring gathering information about
    cognitive state
  • Control self-regulation process.
  • This has strong parallels with recent models of
    emotion.

33
Phillips et als (2003) Model
  • Koriat (2000) argues that metacognition can tap
    into implicit (experience based) knowledge and
    render it into qualitative subjective feeling
    useful for consciously directed behaviour.
  • And that behaviour outcome can feedback to
    modulate the subjective feeling.

34
Neuropsychological Evidence
  • Neuropsych evidence from Goel and Dolan (2003)

RL PFC
  • They asked people to complete belief-congruent or
    incongruent syllogisms during fMRI.
  • Right lateral PFC was activated when belief-bias
    was overcome, consistent with its monitoring
    role.
  • VMPFC was activated when logical reasoning was
    overcome, a region implicated in affective
    processing.

VMPFC
  • They suggest the effects of belief-bias on
    reasoning might be mediated through emotional
    processing.

35
Neuropsychological Evidence
  • Goel and Dolan (2003) conjecture that
  • the right PFC involvement in correct response
    trials is critical in detecting and / or
    resolving the conflict between belief and logic
  • However, evidence from lesion studies and
    psychosis-continuum studies is not clear cut
  • Lesion studies typically implicate R hem damage
  • PFC and / or R hemisphere lesions in
    content-specific delusions (Galloy and
    Richardson, 1994)
  • Anosognosia (Venneri and Shanks, 2004)
  • Alzheimer delusions (Staff et al, 1999)

36
Neuropsychological Evidence
  • Although psychosis-continuum studies typically
    find relatively greater activation in the RH
  • Magical ideation (Leonhard and Brugger, 1998)
  • Belief in ESP (Brugger et al, 1993)
  • Schizotypy (Kravetz et al, 1998)
  • And the imaging studies on people with
    persecutory delusions has shown mixed results on
    asymmetries and functional differences (Blackwood
    et al, 2001)
  • Although medial temporal and ventral striatal
    limbic areas seem important.

37
Summary
  • Affective disturbance is common in people with
    delusions, and delusions are common in people
    with affective disorders.
  • Two main theories have attempted to explain the
    role of affect in delusion formation
  • Defence theories
  • Direct theories
  • There may be a metacognitive or epistemic role
    for affect that could explain its role in
    delusions.
Write a Comment
User Comments (0)
About PowerShow.com