Transcript Document

iIIRG June 2010
Norway
Revising the context reinstatement
component of the Cognitive Interview
for older eyewitnesses.
Rachel Wilcock1 & Coral Dando2
1London
South Bank University
2University of Lancaster
[email protected]
Why is it Important to Consider Older
Adults as Witnesses?
• In the UK in 2006 11.3 million people were of state
pensionable age. This is projected to rise to 12.2
million in 2010, 12.7 million in 2020, and almost
15 million by 2031 (ONS, 2008).
• Older people are more likely to witness crimes and
be victims (Wilcock et al, 2008).
• Older adults are most likely to be the victim of
distraction burglaries (Thornton et al. 2003).
The Effects of Age on Memory
• Overall: older adults have poorer episodic
memory (Balota, Dolan, & Duchek, 2000)
• Specifically:
- Poorer memory for contextual details (Schacter,
Norman, & Koutstaal, 1998)
- Poorer at cognitively complex tasks (e.g. Herman &
Coyne, 1980)
- Older adults believe they have poorer
memories compared to younger adults (Hertzog,
1999)
The Effects of Age on Witness
Memory
• Across 3 mock witness studies older adults (M =
70 yrs) were 20% less accurate in free recall,
13% less accurate in cued recall, and 15% less
complete in their descriptions of the perpetrator
than younger adults (M = 21 yrs) (Yarmey, 2001)
• Older adults more likely to forget central aspects
of event, e.g. presence of weapon and physical
characteristics of perpetrator (Brimacombe et al. 1997;
Yarmey et al. 1984)
The Cognitive Interview for Older
Witnesses
• Some research has found a significant
beneficial effect of CI for older witnesses
(Dornburg & McDaniel, 2006; Mello & Fisher,1996; Wright &
Holliday, 2007)
• Other research has not found a significant
beneficial effect of CI for older witnesses
(Milne, McAlpine, & Bull, 2000; McMahon, 2000)
Context Reinstatement (CR)
• CR based on the encoding specificity
hypothesis is one of the most effective
components of the CI (Milne & Bull, 2002).
• CR may reduce the effects of aging to a certain
extent (Balota, Dolan, & Duchek, (2000).
• However, the manner in which CR is provided
must be appropriate for older adults.
Mental Context Reinstatement for
Older Adults?
• To mentally reinstate context for a whole series of
images requires considerable processing
resources.
• MCR cues given by an interviewer (likely to be a
younger adult) may not be relevant to the
information encoded by older adults.
• Typically after the third or fourth instruction older
witnesses want to explain what happened rather
than silently construct a mental image.
Aims of Study
• To investigate the effectiveness of sketch
CR, verbal CR, and Mental CR, compared
with a control condition on older witness
recall of a mock crime event.
• Hypothesis: Sketch CR would lead to an
increase in correct information compared
to the other conditions.
Participants
• 100 participants (29 male and 71
female) aged between 60 and 81 years,
mean age 69.17 years
• Healthy, independently living, within the
community
• Vision checked
• Screened for dementia and depression
Method
•
•
•

Older adult participants viewed a simulated
crime event shown on videotape
A week delay
Participants were randomly assigned to one of
four interview conditions:
- Sketch Plan CR
- Verbal CR
- Traditional Mental CR
- Control (no CR)
Dependent variables: Correct, incorrect,
confabulated information, and overall accuracy
Examples of Sketches
Correct Information
42
41
40
39
38
37
36
35
34
33
13.02
15.49
10.70
8.40
sketch
verbal
mental
control
No significant differences between interview
conditions F (3, 96) = .756, p = .521.
Incorrect Information
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
0
1.66
2.08
2.27
1.45
sketch
verbal
mental
control
Significant: F (3, 96) = 4.747, p < .004, more incorrect
information recalled during the Sketch interview (M =
4.44) compared with the control interview (M = 2.44).
No significant differences between the other conditions.
Confabulated Information
0.8
0.7
1.02
0.6
1.22
0.5
0.4
.82
.92
0.3
0.2
0.1
0
sketch
verbal
mental
control
No significant differences between interview
conditions F (3, 96) = .299, p = .826.
Accuracy
92.5
92
91.5
91
90.5
90
89.5
89
88.5
88
87.5
3.41
4.57
4.99
5.04
sketch
verbal
mental
control
No significant differences between interview
conditions F (3, 96) = 1.70 p = .173.
Young-Old & Old-Old
Young-Old (N= 52) Old-Old (N = 48)
60 to 69 yrs
70 to 81 yrs
Correct
Incorrect
Confabulations
41.10 (12.52)
3.31 (1.81)
0.54 (.90)
37.35 (11.54)
3.40 (2.20)
0.65 (1.10)
Accuracy
90.87 (4.49)
90.43 (4.75)
There were no significant effects of age group on
recall.
Effect of Interview Condition on
Young-Old & Old-Old
• Young-old: No significant effect of interview
condition on correct, confabulations,
accuracy. For incorrect sketch lead to
significantly more incorrect information (M =
4.55) than control (M = 2.62)
• Old-Old: No significant effect of interview
condition on correct, incorrect,
confabulations, or accuracy
Elicitation of Information in
Sketch Condition
Correct
Incorrect
Confabulations
Accuracy
Mean Recall
During
Sketch
15.00
.92
.20
94.95
Mean Recall
Post Sketch
22.84
2.56
.16
87.76
Mean Total
Free
Recall
37.80
3.56
.36
90.11
Discussion
• From this data Context Reinstatement
appears not to be helpful for older
witnesses.
• BUT difficulty in interpreting the data
because of such large individual
differences
Conclusion
• It may be possible to enhance elderly
witness recall of a crime.
• A memory enhancing interview
designed with the needs of elderly in
mind may be more beneficial than using
the enhanced cognitive interview which
wasn’t designed for this age group.