long-term memory: episodic kimberley clow [email protected]
TRANSCRIPT
Outline What is Episodic Memory?
– Autobiographical Memory Ebbinghaus Memory Stages
– Encoding– Storage– Retrieval
Interactions Between Stages– Depth of Processing– Strategies
Recap
This is the mental model of memory that has developed over the last few lectures
Long-Term Memory
Examples What did you eat for
breakfast this morning?
What was the first university class you attended?
What was the name of your fourth grade teacher?
What was the name of your first best-friend?
What colour was your bedroom when you were 6 years old?
Leftovers from thanksgiving dinner
The history of theatre
Ms. Jarvis
Richie
Blue
Autobiographical Memory Primarily interpretations about an event Information about
– the location of an event– temporal information about the date of occurrence
of an event– the actors, actions, and locations– context-specific sensory and perceptual attributes– imagery
Contains the experience of remembering Duration of the memory can last for years
Types
Personal Memory– image-based representation of a single unrepeated
event
Autobiographical Fact– identical to personal memory, except that the
memory is not image-based
Generic Personal Memory– similar to personal memory, except that the event is
repeated or a series of similar events occur and are represented in a more abstract form
Accuracy
"Memory is a complicated thing, a relative to truth, but not its twin“
• Barbara Kingsolver
Accuracy of autobiographical memories– Factual information:
• .88 correlation among family members
– Emotions and attitudes:• .43 correlation among family members
What Memory System?
Who Wants to be a
Millionaire?
This is Your Life
Ebbinghaus
Criticism
He excluded meaning from the stimuli– We have a great tendency to impose
meaning even on the most meaningless stimuli
• e.g., mentally turning BEF into BEEF
– If memory is studied in absence of meaning, can this tell us how memory normally functions?
• When we do have access to meaning • When do we use mnemonics and other
strategies?
Stages of Memory
Three different stages of processing– Encoding– Storage– Retrieval
Recollecting episodic memories is determined by the interaction of encoding and retrieval processes– How we input material will determine how well we
can output it
Encoding
Depth of Processing– Shallow processing
• Physical features
– Deep processing• Meaning
Memory is affected by the way information is encoded– Not just whether it is in the system– How was it encoded into the system?
Experimental Evidence
Study Phase– Visual
• Does the word contain a letter E?
– Phonemic• Does the word rhyme
with train?
– Semantic• Is it a type of animal?
Test Phase
Not Just the Kind of Processing
Manipulation of sentence contexts– Target: TOMATO
• Simple– She cooked the …
• Medium– The ripe … tasted
delicious
• Complex– The small lady angrily
picked up the red …
Criticisms
Circular Arguments– Deep vs. shallow not well defined– If result is good memory processing must
have been deep instead of shallow Recall vs. Recognition Doesn’t explain why some codes are
better than others– Why difference for yes vs. no response?
Doesn’t explain context effects
Encoding Specificity
Study word pairs– Encode based either
on meaning or sound• Meaning
– Is the target related to the word CAT?
• Sound– Does the target rhyme
with the word CAT?
05
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ENCODEMEANING
ENCODESOUND
MEANING CUESOUND CUE
Context Effects
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5
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35
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ENCODE ONLAND
ENCODEUNDERWATER
RETRIEVE ONLAND
RETRIEVEUNDERWATER
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SAD ENCODING HAPPYENCODING
SAD RETRIEVAL
HAPPYRETRIEVAL
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PLACEBOENCODING
DOPE ENCODING
PLACEBORETRIEVAL
DOPERETRIEVAL
05
101520253035404550
ENCODEMEANING
ENCODESOUND
MEANING CUESOUND CUE
Two Types of Context
Intrinsic context– Has direct impact on the meaning of the to-
be-remembered item• strawberry-JAM vs. traffic-JAM
Extrinsic context– Situation has indirect effect on the to-be-
remembered item• Mood and state dependent learning
– learn words on land or 20 ft under water
Cautionary Note!
Change of environmental context affected recall, but not recognition
Encoding specificity may more generally be thought of as transfer-appropriate processing
Transfer-Appropriate Processing– memory performance is determined by the
degree of similarity between the cognitive operations performed at encoding and those performed at retrieval
When Episodic Memory Fails…His face
is familiar...
HEY BUDDY,I MISSED YOUSO MUCH....
Encoding Strategies
Rehearsal– Type I– Type II
Mnemonics– Single Use– Multiple Use
Organization Imagery
Mnemonics
Three principles:1. Material to-be-learned is structured and
integrated into a preexisting memory framework
2. Material to be remembered must be practiced to form distinctive traces
3. Mnemonic device can be used for both encoding and retrieval by providing effective cues
Single Use Mnemonics
Acronyms– ROY G. BIV
Rhymes– i before e, except after c
Phrases– Spring forward, fall back– Never Eat Shredded Wheat– My Very Earnest Mother Just Served Us Nine Pizzas
Personal Meaning– My student Kate reminds me of Kate Blanchet playing
Galadriel
Multiple Use Mnemonics
The Method of Loci– Dates back to Ancient Greece.
Peg-Word Technique– Taking advantage of pre-existing associations
• “This old man, he played one…”
Imagery
Many mnemonics use visual imagery– Do the method of loci and peg words work
because of their visual basis? Imagery aids learning
– Deeper encoding?– Better storage?– Easier retrieval?
Retrieval
Types of tasks used to test retrieval:– Relearning Task
• Ebbinghaus
– Paired-Associate Learning– Recall
• Free recall• Serial recall• Cued recall
– Recognition
Paired-Associate Learning Task
Forgetting
Reasons for Forgetting– Decay– Interference– Retrieval Failure
Important Terms– Availability– Accessibility
Availability vs. Accessibility
Two groups studied same list of 48 items – Items were preceded by the appropriate name of
the category– Participants were told that they only had to
remember the items themselves At recall one group free recall, the other group
cued recall Results:
– Free recall group: 40 percent– Cued recall group: 62 percent
So information can be available but not accessible
Other Influences
And … Targets presented with weakly associated cue
– glue-CHAIR When asked to RECOGNIZE
– if target is in a new context recognition may fail• fail to recognize table-CHAIR
When given cued RECALL with original associate cue, now successfully remember– glue-?
New associate better cue for remembering item than the item itself!– Don’t remember chair when they see chair with
table, but can recall chair when they only see glue
Dissociation? Patient H.M.
– Episodic & semantic memory prior to surgery intact, but cannot form new memories
Patient E.D.– Semantic memory is impaired yet
episodic memory for the same period is intact
Patient K.C.– Episodic memory processes
disrupted, but semantic memory processes in tact
Not good evidence
Good evidence