Lecture_21

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Lecture 21 – Psyco 350, B1
Winter, 2011
N. R. Brown
Psyco 350 Lec #21– Slide 1
Outline
1. Recovered Memory Controversy
•
•
•
•
Two Approaches
Implanting False Memories
Forgetting CSA
A Third Approach
2. Memory Issues in PTSD
•
Background
Psyco 350 Lec #21– Slide 2
The Recovered Memory Controversy
Psyco 350 Lec #21– Slide 3
The Recovered Memory Controversy
1. Background: The False Memory Hypothesis
2. Implanting False Memory
3. Forgetting CSA
4. The “Middle Ground” Position
Psyco 350 Lec #21– Slide 4
The Recovered Memory Controversy
Background:
• Adults report “recovering” forgotten memories of
childhood sexual abuse (CSA).
• Memories often recovered during therapy.
• Profound emotional & legal repercussions
Psyco 350 Lec #21– Slide 5
The Recovered Memory Controversy
Assumptions – The Recovered (“true”)
Memory Position:
• traumatic memories can be
repressed/suppressed
• recovery techniques produce valid memories of
real events.
• recovering forgotten CSA memories has
therapeutic value.
Psyco 350 Lec #21– Slide 6
Question Assumptions
• Do/can people repress/suppress memories of
CSA?
• Can recovery techniques produce false
memories?
• Does memory recovering CSA memories have
therapeutic value?
Psyco 350 Lec #21– Slide 7
Theoretical Response
Psyco 350 Lec #21– Slide 8
Lindsay & Read (1994)
Memory is fallible & subject to distortion.
Relevant Phenomena:
• Misinformation Effect – blend facts &
suggestion
• Source Amnesia – forget source of information
• Imperfect Reality Monitoring – mistaking
imagined events for real ones
• Reconstruction – past events reconstructed
from fragmentary details and schematic knowledge.
Psyco 350 Lec #21– Slide 9
Clinical Practice (circa, 1990)
When CSA suspected, recovery techniques
employed (over sessions)
Techniques:
• guided imagery
• hypnosis
• dream interpretation
• survivors’ groups
• uncritical acceptance of claims
Psyco 350 Lec #21– Slide 10
False Memories of CSA
“Memory recovery techniques may lead some
clients to create illusory memories.”
-- Lindsay & Read
Imagined and/or suggested events can take on
a realistic vividness and detail w/ extensive
memory work.
Psyco 350 Lec #21– Slide 11
The False-Memory Hypothesis
Psyco 350 Lec #21– Slide 12
False Memories of CSA
Step 1 – create CSA story
Step 2 – elaborate on CSA story
(suggestion, imagery, interpretation, hypnosis,
social facilitation)
Step 3 – forget or mistake origin of CSA story
(source amnesia, failed reality monitoring).
Implication:
• It should be possible to create FM in the lab.
Psyco 350 Lec #21– Slide 13
Implanting False Memories
Psyco 350 Lec #21– Slide 14
Implanting FMs /w Narrative Hyman et al. (1995)
Issue: Can FMs be implanted using clinical
techniques?
Method:
• Preparation: Solicit event descriptions from
parents
• Materials:
– 3 “real” event descriptions
– 1 “false” event description (spill punch bowl at
wedding)
Psyco 350 Lec #21– Slide 15
Hyman et al. (1995): Procedure
• Phase 1:
– Recall as much as possible about each event
& continue to reflect outside of lab.
• 2-day delay
• Phase 2 – repeat procedure
• Phase 3 – repeat procedure
Psyco 350 Lec #21– Slide 16
Hyman et al. (1995): Results
• true memories increase
across phases
• false memories increase
across phases
– Phase 2 FM = 25%
• Accessing background
knowledge predicts FM
– FMS for 11 or 30 Ss
who accessed BK
– FM for 2 of 21 Ss who
did not access
Psyco 350 Lec #21– Slide 17
Hyman et al (1995): Sample FM
Background
Knowledge
Psyco 350 Lec #21– Slide 18
Hyman et al (1995): Sample FM
Psyco 350 Lec #21– Slide 19
Hyman et al. (1995): Results
• Accessing background knowledge predicts FM
– FMs for 11 or 30 Ss who accessed BK
– FMs for 2 of 21 Ss who did not access BK
Interpretation:
suggestion + BK + source confusion FM
Psyco 350 Lec #21– Slide 20
Creating FMs w/ Photos:
Wade, Garry, Read, Lindsay (2002)
Method:
• 3 “real” childhood
photos
• 1 doctored childhood
photo
Task:
• recall as much as
possible
• three phases  1 week
apart
Psyco 350 Lec #21– Slide 21
Creating FMs w/ Photos:
Wade, Garry, Read, Lindsay (2002)
Results for False Photos:
• 1st Interview: 30% FMs
• 3nd interview: 50% FM
Conclusion:
Photos compiling for
support of generating
false event and accept
false memory.
Psyco 350 Lec #21– Slide 22
Implanted False Memories
Psyco 350 Lec #21– Slide 23
Three Stages Required to Implant FMs
Hyman & Loftus (1998)
1.
•
•
2.
Plausibility Assessment/acceptance
source (family, experts)
content (likelihood, consequentiality)
Memory Construction (creation of a plausible
imagined event)
• Actively relate proposed event to self-knowledge
• Imagery, journaling, dream interpretation
3. Source Monitoring Error.
• Situational/social demands
• Delay
• Repetition
Psyco 350 Lec #21– Slide 24
Implanting FMs
FM research:
• demonstrates FMs can be implanted
• refines techniques for creating FMs
Ethical Question:
• Is it time for a moratorium on this type of
work?
Psyco 350 Lec #21– Slide 25
Forgetting CSA
Psyco 350 Lec #21– Slide 26
A Prospective Study: Williams (1994)
Participants:
• 129 women contacted 17 yrs after reported
sexual abuse
Age at report:
• 10 months to 12 years
Task:
• 3 hr interview – questions about
– sexual history.
– NOTE: “Index” event not specifically probed
Psyco 350 Lec #21– Slide 27
Williams (1994): Results
• 38% failed report index event
– suggest repression-based
forgetting of CSA very
common.
• Victim-perpetrator relation
affected recall
– by-stranger (82%) > by-relative
(53%)
• recall  as degree of force 
• Younger victims less likely to
recall event
Psyco 350 Lec #21– Slide 28
All respondents
129 – 100%
remembered
80 – 62%
Psyco 350 Lec #21– Slide 29
not remembered
49 – 38%
Williams (1994): Decomposing the Non-responses
38% failed to report index event.
Psyco 350 Lec #21– Slide 30
All respondents
129 – 100%
remembered
80 – 62%
other abuse
33 – 26%
Psyco 350 Lec #21– Slide 31
not remembered
49 – 38%
no other abuse
16 – 12%
Williams (1994): Decomposing the Non-responses
38% failed to report index event.
But:
68% (33/49) of non-responders report other
abuse.
Non-repression based explanations
• schematization
• retrieval (motivational) failure
• coding mismatch
Psyco 350 Lec #21– Slide 32
All respondents
129 – 100%
remembered
80 – 62%
other abuse
33 – 26%
under 3 yrs
5 – 4%
Psyco 350 Lec #21– Slide 33
not remembered
49 – 38%
no other abuse
16 – 12%
3 or older
11 – 8.5%
Williams (1994): Decomposing the Non-responses
Thus, “Pure” failure to report CSA relatively uncommon
(8.5%):
“failure to report” may reflect:
• willingness to disclose
• forgetting
Psyco 350 Lec #21– Slide 34
Prospective Study – Replication
Goodman et al (2003)
• n = 168; failure to report = 10%
Alexander et al (2005)
• Memory for CSA  w/ severity of trauma
Psyco 350 Lec #21– Slide 35
Main Points
• FMs can be implanted.
• CSA can be forgotten, but generally is not.
Psyco 350 Lec #21– Slide 36
A Third Perspective
Psyco 350 Lec #21– Slide 37
Three Views
1. Repressed Memory View
– Traumatic Dissociative Amnesia underlies ALL
recovered memories.
2. False Memory View
– ALL recovered memories are implanted
3. Middle Ground (Schooler, McNally, Geraerts)
– CSA events can be forgotten and later recalled
– Repression/dissociative processes not
required/involved
Psyco 350 Lec #21– Slide 38
Middle Ground
Three States re: CSA memory
1. Continuous Memory
• Discontinues Memories
2. Spontaneous recovery
3. During-therapy recovery
Psyco 350 Lec #21– Slide 39
Middle Ground: Evidence
• Corroborated case studies exist (Schooler)
• Between-group corroboration rates (Geraerts et al,
2007)
45% -- continuous group (n=71)
37% -- spontaneous group (n=41)
0% -- recall-in-therapy group (n=16)
• Rated-surprise:
spontaneous >> recalled-in-therapy
Psyco 350 Lec #21– Slide 40
Characteristics of Spontaneous Recovery
(McNally, 2007)
Modal nature of recovered abuse event
• Victim’s age: 7 or 8
• Non-violent molestation
• Perpetrator: close relative
• (Recalled) initial reaction
– “confused and upset, but not terrified”
– “not fully understood… as sexual abuse.”
Psyco 350 Lec #21– Slide 41
“Normal” Spontaneous Recovery of CSA
• T1
– CSA little understood/discussed.
• CSA “forgotten” like other past events
• T2
– Context-cued recovery of CSA event
– CSA understood as abuse, leading to...
– “intense emotional distress”
Psyco 350 Lec #21– Slide 42
The Logic of Repression
Assumptions:
• CSA is always traumatic
• Normally, traumatic events are NOT forgotten
• CSA events sometimes forgotten
Therefore:
1. Forgetting can’t be “normal”
2. So a special forgetting process must evoked by CSA
Psyco 350 Lec #21– Slide 43
The Logic of “Middle Ground”
Assumptions:
• CSA is NOT always traumatic
• Memory for non-traumatic events is normally
discontinuous.
• CSA events sometimes forgotten
Therefore:
1. Forgetting can be “normal”
2. So a special forgetting process need NOT be evoked
by CSA events
Psyco 350 Lec #21– Slide 44
Summary: A Cognitive Perspective on
Recovered Memories
• Traumatic events are well remembered.
• Continuous memory for CSA is normal.
• CSA can be forgotten & recovered.
• Repression/dissociation not required.
• Spontaneous CSA memories more credible than
recalled-in-therapy memories.
• Because, memory recovery techniques can produce
false memories.
Psyco 350 Lec #21– Slide 45
Post-traumatic Stress Disorder:
Background
Psyco 350 Lec #21– Slide 46
DSM-IV Criterion A
The person has been exposed to a traumatic event in
which both of the following have been present:
(1 – The Event) The person experienced, witnessed,
or was confronted with an event or events that
involved actual or threatened death or serious injury,
or a threat to the physical integrity of self or others
(2 – Peritraumatic Reaction) the person's response
involved intense fear, helplessness, or horror.
Psyco 350 Lec #21– Slide 47
DSM-IV Criteria B-F
B. reexperiencing of the traumatic event
C. avoidance of stimuli associated w/ trauma and
numbing of general responsiveness
D. increased arousal
E. symptoms present for more than 1 month
F. clinically significant impairment in social,
occupational, or other important areas of
functioning
Psyco 350 Lec #21– Slide 48
Prevalence
• Traumatic events “common”
– In US, experienced by 50%-60% of population
• PTSD symptoms in ≈ 10% of population
Psyco 350 Lec #21– Slide 49
Risk Factors
• Previous Traumatic Experiences
• History of Abuse
• Family History of PTSD or Depression
• History of Substance Abuse
• Poor Coping Skills
• Lack of Social Support
• Ongoing Stress
• Sex
• Neuroticism
Psyco 350 Lec #21– Slide 50
Comorbidity
Psyco 350 Lec #21– Slide 51
Slide 51
The Dose-Response Model
• D-R Model predicts: PTSD w/ severity of trauma.
• “The relationship between dosage of trauma and
resultant psychopathology is far from straight
forward.” – McNally, 2003, p, 223
• Possible reasons:
– Nonlinear relation
– Problems w/ retrospective self-report (distorted/biased
estimates of dosage).
Psyco 350 Lec #21 – Slide 52
Estimation Theory Meets PTSD
• Estimation bias & strategy related
• We know:
– memory contents restrict strategy selection
• If mental state affects strategy selection, then
dose estimates may be systematically biased.
Psyco 350 Lec #21– Slide 53
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