Psych 240 Lecture October 27th

What are the advantages of construction of memory?

Allows us to "fill in the blanks" Useful to understand decisions, solve problems, make decisions, etc.

Is episodic memory really constructive?

Constructive idea implies original memory changes -when retrieve overwrite original memory Alt perspective -We often make incorrect memory judgements -inject additional inferences, make source confusions -then mistakenly identify upshot as our "memory" We have poor source monitoring (original memory vs. inference vs. source/other memory) -We are overconfident in our "memory"

Source Monitoring Error

Failure to distinguish the source of the information MPI is misattributed to the original source

Loftus and Palmer (1974)

Hear "smashed" or "hit" in description of car accident Those hearing "smashed" said the cars were going much faster than those who heard "hit" This illustrates the power of suggestion

Post-Identification Feedback Effect

Increase in confidence due to confirming feedback after making an identification

What can be done to improve accuracy?

Inform witness that perpetrator may not be in the lineup -use fillers in lineup similar to the suspect -use "blind" lineup administrator, get immediate confidence rating (without prior feedback) Improve interviewing techniques -Cognitive interview- large increase in correct info --allow witness to report w/out interruption, questions, etc.

Hyman et al. (1995)

Parents described childhood experiences -experimenters interviewed participants about both real and bogus childhood experiences Results: -at first bogus experiences (correctly) not remembered -Later some of these were erroneously recalled -Probably because of familiarity/source confusion

Wells & Bradfield (1998)

Participants view security videotape with gunman in view for 8 seconds Everyone identified someone as the gunman from photographs afterwards The actual gunman's picture was not presented

Potential Sources of Error in Eyewitness Testimony

Perception/attention effects familiarity/source misattribution suggestion attention can be narrowed by specific focus: weapon focus

Stanny and Johnson's "weapons focus" experiment, investigating memory for crime scenes, found that (2000)

Presented film of simulated crime -two film versions "shoot" and "no-shoot" Results: recall worse across the board in "shoot" condition-even for details of weapon -illustrates impact of weapon focus

Retroactive Interference

Recent learning interferes with memory for prior learning, but original memory is not replaced -Clearly could play a role in MPI effects w/inference

How can you explain suggestion effects?

Retroactive Interference and Source Monitoring Error

Misinformation Effect

incorporating misleading information into one's memory of an event, caused by misleading info presented after witnessing an event To study, provide misleading postevent info (MPI)

Lindsey (1990) Source Monitoring

Saw slides depicting man stealing computer Everyone got MPI later, but -difficult group- immediate MPI, narrator gender same -easy group- delayed MPI, narrator gender changed Final memory test all told to ignore MPI Difficult group: 27% source monitoring(from MPI) errors Easy group: 13% errors Bottom line: source monitoring is important in MPI effects

Loftus and coworkers (1975)

See slides of traffic accident with stop sign -Some get MPI: yield sign -Relative to controls, MPI group recalls yield sign more

Disadvantages of Construction of Memory

Sometimes we make errors Sometimes we misattribute the source of information Was it actually presented, or did we infer it?

Ross et al. (1994)

Source misattribution First see film of teacher reading -Exp group: male -Control: female Then see the same female teacher being robbed Test: ID perpetrator from photo spread

Errors due to suggestion

Suggestive questioning Misinformation effect Confirming feedback Post-identification feedback effect

Errors in Eyewitness Testimony

Testimony by an eyewitness to a crime about what he or she saw during the crime One of the most convincing types of evidence to a jury Assume that people see and remember accurately But, like other memory, eyewitness testimony can be inaccurate Mistaken identity Constructive nature of memory

Is episodic memory implicit or explicit?

explicit