Part XPart XMemory: Picture Memory, Distortions, etc.

El b i d i di1. Elaborations during encoding

2. Inability to encodey

3. Misleading information at encodingencoding

4. Retrieval biases

5. Verbal processing

fPlease recall all of the words that you were asked to learn at the beginning of the lecture.

How racial stereotypes distort social perceptions:After briefly viewing this picture, one participant described it to a second participant, who described it to a third, and so on. After six rounds of

i i h fi l f l d h bl d h ld b hcommunication, the final report often placed the razor blade held by the white man into the black mans’ hand.

Please take a moment to answer the questions about the video you watched earlierabout the video you watched earlier.

H f t th i h th hHow fast were the cars going when they _____ each other?

VERB USED ESTIMATE (in MPH)Smashed† 40.8Collided 39.3Bumped 38.1 u ped 38Hit 34.0Contacted 31.8

O k l h d b k† One week later, these participants reported seeing broken glass (when there was none)!!!!

Robbery and Murder experiment (Loftus, 1974)

Three Groups▪ Circumstantial Evidence▪ +Eyewitness Testimony▪ +Eyewitness Testimony

with 20/400 visionwith 20/400 vision

Convenience Store experiment (Brigham et al., 1982)p ( g , 9 )

Unusual/Distinct ActionsDirectionsPaying in Change

Later memory2 vs. 24 hours later

Videotaped crimeMisled by another “witness”2 DVs (Loftus & Greene, 1980)

Face ReconstructionFace Recognition

L i R i iLures in RecognitionSanders (1984)

Jury Ignorance Cutler, Penrod, & Dexter, 1990

ff f fEffects of Misleading InformationWhy does this happen?

Another Loftus accident experiment

Stop and Yield Signs

Before misleadingBefore misleading information:

After misleading information:

fWhy does Loftus’s explanation sound bad?

What else might explain this?

d h hLet’s do the math

New Explanation of Loftus Miller & Burns (1978)

Control Group

New Explanation of Loftus, Miller, & Burns (1978)

Expected Total

% of Subjects Performance CorrectRemember 40% 100% 40%

Don’t Remember 60% 50% 30%Total 70%

Misled Group

Remember 40% 100% 40%

Don’t Remember 60% 25% 15%Total 55%

See: See:

Hear: “7-Up” Hear: “7-Up”

Test: Coke or 7-Up? Test: Coke or Sunkist?

Control Group

Expected Total% of Subjects Performance Correct

Remember 40% 100% 40%4 4Don’t Remember 60% 50% 30%

70%

Misled Group

Expected Total% of Subjects Performance Correct% of Subjects Performance Correct

Remember 40% 100% 40%Don’t Remember 60% 50% 30%

70%

Forced Choice procedure

h ffNew way to test this effect

l d lResults and implications

l f hBest explanation for these errors?

See:See:

Hear: “7-Up”7 p

Test Coke? T t h i di id llTest: Coke?7-Up?Sunkist?

Test each individually

LEARN A B LEARN A C TEST A BLEARN A-B LEARN A-C TEST A-B

Interference from new learning

Karl Lashley vs. Gordon BowerSearching for engrams▪ Unsuccessfully, gave up

M i i l i▪ Memory is not a single unit▪ Composed of multiple components (features)

Emotional featuresSemantic featuresEpisodic featuresVisual/Auditory featuresVisual/Auditory featuresMore features…

f fComposed of many features, just like any other memory…

h h d l dWhat have we reviewed already?

h dShepard (1967)2-AFC Recognition▪ Words vs Pictures▪ Words vs. Pictures▪ Delay vs. Immediate

Standing (1973)2-AFC Recognition

D l I di▪ Delay vs. Immediate

Why is it so good?y g

Faded Snapshot Image decayImage decayImpaired access, random distortion

ConstructivistFeatures constructed and lostPredictable biases

Hierarchical Organization (Stevens & Coupe, 1978)

Map example

Comparison of cities▪ Farther East: Reno or

San Diego

Why does this happen?

Grouping and Categories(Hirtle & Jonides, 1985)

Distances within vsDistances within vs. between categories

Near vs. Distant Buildings

Wh d hi h ?Why does this happen?

fCognitive Reference Points (Holyoak & Mah, 1982)

Distances from certain landmarks

Distances TO and FROM▪ San Francisco to Salt Lake City▪ New York to Philadelphia

h d h hWhy does this happen?

lAlignment (B. Tversky, 1981)

South and North AmericaSouth and North America

Why does this happen?Grouping/CategoriesGrouping/Categories

Rotation (B. Tversky, 1981)

Back to South AmericaR t tiRotationSimilar to another bias?

d k ff d ll lLandmark Effect (Sadalla et al., 1980)

Wh d k f ll h bi i i ?What do we take from all these biases in picture memory?BackgroundOrientationOrientationRelation of figuresReference Frame

Whi h i h h ?Which is the correct theory?

Memory is feature based (“multicomponent”)y p

M EMemory Errors

Eyewitness Testimony

Picture Memoryy

Biases in Picture Memory