REMEMBERING: THE ROLE OF THE CUE

• Remembering as “ecphory”– A synthesis of engram, current state,

and retrieval cue (Semon, 1909)

• Cue Specificity– Free versus cued recall

Tulving & Psotka (1971)

study categorized listfree recall: .40

then cued recall: .70

– Recall versus recognition

Tulving & Watkins (1973)

study word list (e.g., grape)then cue: vary stem size (gr-- = 2)

0 (recall) .25 full (recognition) .85

• Encoding/Retrieval Specificity(Tulving, 1973)– Compares E/R Match versus Mismatch– Small but reliable effects of:

• Verbal/associative “context”• Encoding task and level• Physical environment• Internal state and mood

– Larger effects when other cues weak

Eich (1975): Marijuana / Placebo

Study categorized list of 48 words

Study Test Free Recall Cued Recall

Pla Pla 11.524.0

Pla Mar 9.923.7

Mar Pla 6.722.6

Mar Mar 10.522.3

• E/R Specifity (cont’d)– Larger effects with “contextual

encoding”

Eich (1985):

study / test room match / mismatch

study long word list

imagery instructions:isolatedintegrate with environment

0

0.1

0.2

0.3

0.4

0.5

integrated isolated

Imagery instructions

Pro

ba

bil

ity

of

Re

call

E/R Match E/R Mismatch

CUE-DEPENDENT FORGETTING

• Occlusion– Cue activates other memories

– Watkins’ (1979) cue overload principle– The “fan effect”– Classic associative interference

Retroactive Interference Design

RI A-B A-C A-Bcontrol A-B rest A-B

Proactice Interference Design

PI A-C A-B A-BControlrest A-B A-B

ASSOCIATIVE INTERFERENCE AND FORGETTING

task: study and remember lists of paired-associates (A-B)

C

BA

learning AC interferes with AB

AB learned first: Retroactive (RI)AC learned first: Proactive (PI)

RETROACTIVE INTERFERENCE IN PAIRED-ASSOCIATE MEMORY(Barnes & Underwood, 1959)

task: study and remember lists of paired-associates

10 Trials of AB pairsthen

1 to 20 trials of AC pairs

0

20

40

60

80

100

Cu

ed

Re

ca

ll (

%)

0 5 10 15 20

# Trials on AC Lists

"C" recall

"B" recall

is AB association erased (“unlearned”)?NO: recognition-matching still good

• Occlusion (cont’d)– Part-list cuing effects (Roediger, 1973)

categorized lists, seven instances

cue with:

pc(remaining) category name only .63 and one instance .62 and two instances .56 and five instances .52

– Output interference• Recall of items within a category

reduces PC of remaining items

– (Smith 1971): categorized lists - controls order of category cues - recall decreases across order

• Occlusion (cont’d)– Retrieval-induced forgetting (Anderson,

Bjork & Bjork, 1994)

Study sets of category-instance pairs

FRUIT - orange; FRUIT - apple, etc

TOOL - drilll; TOOL - hammer, etc

Retrieval practice on half of some categories:

FRUIT – or_____

Cued recall test of all pairs: FRUIT - ?

RP+ RP- No RP“good” e.g.’s .81 .41 .56“weak” e.g.’s .66 .35 .41

– Gargano & Chandler (1999): less interference with “study” practice only

– Veling & van Kippenberg (2004): recognition speed for target words

RP+: 678 ms RP-: 810 ms NRP: 759 ms

CUE-DEPENDENT FORGETTING (CONT’D)

• Suppression– Target is inhibited, becomes less

accessible to other cues

“cross-cue” forgetting observed in some studies:

Anderson & Spellman, 1995:

practiced within-categRED-blood

.74unpracticed within

RED-tomato.22

unpracticed across, relatedFOOD-strawberry

.22unpracticed across, unrelated

TOOL-drill.38

• Suppression (cont’d)

– But some failures too:

Gargano & Chandler (1999)

Type of Cue during…

practice test RP- No RP

FRUIT-or___ FRUIT-or___ .71 .79

FRUIT-__nge FRUIT-or___ .78 .80

Fischler & Woods (1985):

train AB, DB associates

RI with half of A stimuli: AC pairs

strong forgetting of A – Bno forgetting of D - B

IS MEMORY PERMANENT?

• The arguments for and against– Some memories seem to “last a lifetime”– But they may not; and others don’t

– Much of forgetting seems to be “retrieval failure”

– But sometimes all cues fail

– Brain stimulation seems to awaken specific memories (Penfield, 1952)

– But the effect is rare (40 of 520 patients), and events seem more schematic than episodic

– Interference in the lab dominates forgetting– But the “forgetting function” is beautifully

time-dependent (Power Law)

– No confirmed mechanism of “decay” at neural level

– But some evidence, and a long way to go