3/20/2014
Seven Sins of Memory
Memory Retrieval 2
Seven Sins of Memory
Dan Schacter (Harvard)
Compared seven common memory errors to deadly sins
If you avoid these you are rewarded with good memory
But, sinning is not all bad and serves a purpose
How good is everyday memory?
Shepard (1967)
Shepard (1983)
Patterson and Baddeley (1977)
Seven Sins of Memory
The sins
Transience
Absent Mindedness
Blocking
Misattribution
Suggestibility
Bias
Persistence
Each sin tells us something about how memory works
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Transience
Deterioration of memory
Hermann von Ebbinghaus (1885)
Studied meaningless, nonsense syllables (wuj)
Tried to recall syllables
Forgetting curve
Absent Mindedness
Lapses of attention resulting in poor encoding
Change blindness
Inattentional blindness
Simons & Chabris (1999)
Hyman, et al. (2010), “Did You See the Unicycling Clown?...”
Blocking
When trying to retrieve memory, something blocks access
Examples
Proactive interference
Retroactive interference
Release from PI shows we can unblock
Tip of the Tongue phenomenon
von Restorff effect
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Blocking
Tulving and Pearlstone (1966)
Related to von Restorff effect
As number of memorized items per category increases, memory
for individual items decreases
Subjects studied lists of 12, 24, or 48 words
For each length the number of items/category was 1, 2 or 4
Free recall vs. category cued recall
Blocking
Tulving and Pearlstone (1966) Results
Number of items/category influenced cue effectiveness
More distinct a cue = better memory
Mean # Words Recalled
36
Cued Recall
32
Free Recall
28
24
20
16
12
8
4
1
2
4
12 Items
1
2
4
24 Items
1
2
4
48 Items
List Length and Number of Items Per Category
Blocking
Retrieval induced forgetting
Anderson, Bjork & Bjork (1994)
Intervening test of some items inhibits memory for other items
Three phases to the experiment
Study Phase
Drink
Vodka
Rum
Gin
Bourbon
Ale
Whiskey
Fruit
Tomato
Strawberry
Banana
Orange
Lemon
Pineapple
Practice Phase
Test Phase
-------------
Drink _____
Drink _____
Drink _____
Drink _____
Drink _____
Drink _____
Condition
Unpracticed-unrelated item (NRp)
Unpracticed-unrelated item (NRp)
Unpracticed-unrelated item (NRp)
Unpracticed-unrelated item (NRp)
Unpracticed-unrelated item (NRp)
Unpracticed-unrelated item (NRp)
Unpracticed-unrelated item (NRp)
------Fruit Or_____
Fruit Le_____
Fruit Pi______
Fruit _____
Fruit _____
Fruit _____
Fruit _____
Fruit _____
Fruit _____
Unpracticed-related item (Rp-)
Unpracticed-related item (Rp-)
Unpracticed-related item (Rp-)
Practiced Item (Rp+)
Practiced Item (Rp+)
Practiced Item (Rp+)
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Blocking
Anderson, Bjork & Bjork (1994)
Memory better for NRp items than Rp- items
Suppression or “inhibition” of unpracticed category items
% Correct Recall
100
FRUIT
80
DRINK
60
40
20
orange
banana
vodka
whiskey
Rp+ 81%
Rp- 40.3%
NRp 56%
NRp 56%
0
Rp+
Rp-
NRp
Misattribution
Assigning memory to the wrong source
Bystander effect
Attributing the actions of one person to another
Not the same bystander effect as in social psychology
Memory conjunction errors
Combining/blending information from two sources
Study:
spaniel
varnish
Retrieve: Spanish
Misattribution
Payne, Jacoby and Lambert (2004)
Examined influence of stereotypical black names versus white
names on memory for occupations
Memories of events are not isolated and independent
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Suggestibility
Tendency to incorporate information (often misleading)
into our recollections
Leading questions by attorneys
Coercive questioning by police
“That was a nice blue shirt Bob was wearing.”
Loftus and Palmer (1974)
Misinformation Effect
Video of car accident
“About how fast were the cars going when they _____ each other?”
hit, smashed, collided, bumped, or contacted
Suggestibility
Loftus and Palmer (1974) Results
Speed estimates were influenced by the verbs “severity”
Mean Speed Estimate (mph)
45
43
41
39
37
35
33
31
29
27
25
Contacted
Hit
Bumped
Collided
Smashed
Verb Used in Question
Suggestibility
Loftus and Palmer (1974) Results
Question wording also causes us to think something was present
“Was there any broken glass in the accident?”
Saw Broken
Glass?
Yes
No
Verb Used in Sentence
“Smashed”
“Hit”
n = 16
n=7
n = 34
n 43
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Bias
Feelings, beliefs, and worldview distort
memory for events
Bryant and Brockway (1997)
Hindsight bias (hindsight is always 20/20)
“Feel like we knew something all along”
Examined hindsight bias of the OJ Simpson verdict
Asked about likelihood of guilt 2-hours before and 2-days after
Ronald Regan as the ‘deficit and unemployment fighter’
PLEASE don’t get me started on this…I BEG YOU!!!!
Persistence
Remembering things we wish we could forget
White bear phenomenon
Associated with post-traumatic stress disorder
False Memory
Encoding items related to a critical item/event can lead one to
falsely remember seeing that item/event
Deese, Roedigger & McDermott (DRM) False Memory Effect
Study a list of words related to a critical lure
Recall or recognize the list items
Studied item
Critical lure
Non-studied associate
Studied Item
Non-Studied Associate
Critical Lure
65%
14%
41%
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False Memory
Activation/source-monitoring account
Associates activate the lure during encoding
During retrieval, subjects have difficulty determining the source
of activation of the critical lure
snooze
night
pillow
SLEEP
dream
rest
wake
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