Flashcards
Week 11: Face recognition and EWT
Cards in this deck (23)
- 1What behaviour studies show how we process faces. (Inversion effect)Inversion effect much less apparent for objects than faces. Faces= processed configural (distinguished by parts).
Dog breeders show inversion affect = non faces and faces processed same way, but affected by familiarity. - 2What do brain imaging studies say about how we process faces? (Experts?)Fusiform gyrus is face selective BUT when trained to the features of 'greebles' the fusiform area lights up.
So we're just experts for certain stimuli, and faces are one of them due to exposure. - 3Explain Bruce and Young's (1986) theory on face recognition (unfamiliar vs familiar faces).Sequential processes- face is seen
1) Structural encoding occurs
2) if unfamiliar focus on expression, facial speech analysis and directed visual processing
3) familiar face- recognition unit, person identity node, name generation
4) Move back and forth in the cognitive system. - 4How does familiarity affect facial recognition?unfamiliar faces are processed for identity in a different way than familiar.
- 5How does variation of a face impact recognition?.
- 6What is signal detection theory and how does it relate to EWT?2x2 grid
1) Type I error (false positive) reject null hypothesis when it is true
2) Hit- reject null hypothesis when it is false
3) correct rejection- fail to reject null hypothesis when it is true
4) Type II error - false negative-miss- fail to reject the null hypothesis when it is false
Null hypothesis in this case is the incorrect suspect. - 7In lab line ups, how good are we at accurately detecting a face from a line up?70% hits
70% correct rejections - 8How does unfair line ups influence eyewitness choosing (unfair= police suspect stands out).When nothing is done to make the line up fair (by making the individual stand out LESS), more likely to choose more, and find it harder to distinguish between innocent and guilty individuals.
- 9What are system variables and which ones can influence EWT?Things the police can control, such as:
Instructions, content, presentation method, behavioural influence and questioning method. - 10What are estimator variables and which ones can influence EWT?Things that police cannot directly control such as attention, lighting, viewing distance, disguises, capability, weapon presence, race, state of EW.
- 11How does eyewitness instructions influence EWA? (Malpass & Devine, 1981) How does providing instruction influence identification? Steblay 1997When given the choice to not choose rather than suggesting they have to choose, participants were more accurate.
Steblay- 1997 Instructions lead to a large reduction in mistaken identification (41.6%) and and only a very small reduction in accurate identifications (1.95%) - 12How does content/ line up filler influence EWA?Target should not stand out or blend in, they should be based on the target. fillers can be based on verbal descriptions (Wells et al., 1994) although best way is unclear (Wells & Olson, 2003).
Using the tredoux E- statistic should be close to the number of faces in the line up. Each person should be chosen from a description the same amount of times without initial exposure - 13How does presentation method influence EWA?Simultaneous has been seen to improve EWA in comparison to sequential (Lindsay and Wells, Steblay et al)
- 14How does behavioural influence influence EWA? How does contact with suspect influence EWA? (Haw and Fisher, 2004)The person who is administering the line up is very important and the need for a double blind is well established. If the person administering the line up knows who they are, and spends more time/ contact with the suspect, they are more likely to get that person (unconsciously) selected by the EW.
- 15How does questioning method influence EWA?Original questioning methods led to unreliable memory recall due to interruptions, predetermined questions, expectation of answers and poor timing
- 16What is the cognitive interview?fisher and Geselman developed the CI, which aims to build rapport, recreate context, open ended narration, and have closure.
CI is not always used, but is when there are more serious crimes.
Is the success due to Unconditional positive regard/ rapport like Rogers uses in psychotherapy, or because of cognitive memory techniques? - 17How does lighting affect EWA?.
- 18How does the state of an eyewitness (stress, intoxication) affect EWA?Inverted U- too much stress leads to reduced accuracy and recall of details.
Low or high stress reduces accuracy. Need a middle ground
BUT accuracy was better in the low than the high stress. - 19How does item value affect EWA? Leippe et al; Hosch et al., 1984ID of suspect:
Identification higher when more valuable item taken.
Identification lower when own property was taken. - 20How does retention interval affect EWA?Memory erodes over time
Longer delays leads to fewer identifications- 51 vs 61% and more false identificants-32 vs 24% - 21What are postdictor variables- which ones are mentioned in the lecture?Explanation after the fact
Some estimator variables
Attention
Sensory capabilities
State of witness
Post-dec confidence
RT
Individual difference
Multiple line ups
Foil identifications - 22Explain Sauerland and Sporer's 2009 study on post decision confidence and decision time on EWA?those who responded quickly and were confident were more accurate at recalling the passers by than those who were slow and not confident.
I know answers...higher identification
vs familiar= lower identification
Non chooser= person not present= more confident and faster than nonchooser who could not remember. - 23How do individual differences affect EWA?Participants asked to do a line up ID, then to choose the correct face (with the face present at the top) from a group of 10.
Accuracy on line up correlates with the 1 in 10 task.
This only works for choosers.
If they make no decision, there is no correlation.
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- Year 4 SP633 Applied psychology Flashcards on Week 11: Face recognition and EWT, created by chantel Smith on 01/03/2021.
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- chantel Smith
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