Eyewitness Testimony
Reconstructive memory
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Schema driven errors
Effect of leading questions
Other factors
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Weapon focus
Effects of anxiety/arousal
Retrieval cues
www.psychlotron.org.uk
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Reconstructive Memory
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Bartlett (1932)
Memory is not a direct record of what was
witnessed
What is encoded and how it is retrieved
depends on:
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Information already stored in memory
How this info is understood, structured and
organised
www.psychlotron.org.uk
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Reconstructive Memory
Schemas
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Knowledge structures that relate to commonly
encountered objects, situations or people
Enable us to predict events, make sense of
unfamiliar circumstances, organise our own
behaviour
Act as filters to perception & recall
www.psychlotron.org.uk
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Computer Information Processing
BANG!
www.psychlotron.org.uk
Can you
wreck a
nice
beach?
Schema Driven Processing
Yes. I can
recognise
speech.
www.psychlotron.org.uk
Can you
wreck a
nice
beach?
Bartlett (1932)
Input
Schema
Output
‘Turf cutter’
Bartlett (1932)
www.psychlotron.org.uk
‘Pickaxe’
Bartlett (1932)
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War of the Ghosts
When recalled by UK PPs:
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Shorter
Less detailed
Some details changed (e.g. seal hunting
changed to fishing)
More ‘Western’ structure
www.psychlotron.org.uk
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EWT: Schema Driven Errors
Witnesses to crimes filter information
during acquisition & recall
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Their schematic understanding may influence
how info is both stored & retrieved
Distortions may occur without the witness
realising
www.psychlotron.org.uk
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Past experiences
Assumptions about
what usually happens
Stereotypes & beliefs
about crime &
criminals
www.psychlotron.org.uk
EWT: Schema Driven Errors
EWT: Leading Questions
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Loftus (1970s onwards)
Effect of leading questions on recall
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Leading questions introduce new information
Leading info may activate wrong schemas in
witness’ mind
Consequently, witness may recall events
incorrectly
www.psychlotron.org.uk
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EWT: Leading Questions
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Loftus’ studies using film/video/slides road
accidents
‘How fast were cars going when they hit…’
or ‘…when they smashed…’?
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‘Smashed’ led to higher speed estimates
‘Did you see a/the broken headlight’?
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‘The’ produced more affirmative (incorrect)
responses
www.psychlotron.org.uk
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EWT: Leading Questions
Loftus’ research usually lab based:
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Restricted samples (students)
Artificial stimuli (slides, videos, not real
events)
Potential for demand characteristics to
influence responses
No legal/moral consequences for inaccurate
answers
www.psychlotron.org.uk
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EWT: Leading Questions
EWT most affected by leading Qs when:
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Witness
them
Witness
Leading
Leading
believes questioner knows more than
does not realise they may be misled
information is peripheral, not central
information is not blatantly incorrect
www.psychlotron.org.uk
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When a weapon is
used to threaten a
victim, their attention
is likely to focus on it
Consequently, their
recall of other
information is likely to
be poor
www.psychlotron.org.uk
EWT: Weapon Focus
performance
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arousal
Memory is most
effective at moderate
arousal levels
If the witness was in
a state of extremely
low or high arousal
then recall may be
poor
www.psychlotron.org.uk
EWT: Arousal Effects
EWT: Retrieval Cues
Recall typically takes place in a different
context to acquisition
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Lack of retrieval cues (state and context) can
inhibit recall
Reconstruction of the events (either
imagination or simulation) can lead to
enhanced recall
www.psychlotron.org.uk
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