Transcript Long-Term Memory

Long-Term Memory: Episodic
Kimberley Clow
[email protected]
http://instruct.uwo.ca/psychology/130/
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?
This is Your Life
Who Wants to
be a
Millionaire?
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?
50
45
40
35
30
25
20
15
10
5
0
MEANING CUE
SOUND CUE
ENCODE
MEANING
ENCODE
SOUND
Context Effects
40
50
45
40
35
30
25
20
15
10
5
0
35
30
RETRIEVE ON
LAND
RETRIEVE
UNDERWATER
25
MEANING CUE
SOUND CUE
20
15
10
5
0
ENCODE
MEANING
ENCODE ON
LAND
ENCODE
SOUND
ENCODE
UNDERWATER
30
90
80
25
70
60
SAD RETRIEVAL
50
20
PLACEBO
RETRIEVAL
DOPE
RETRIEVAL
15
40
HAPPY
RETRIEVAL
30
20
10
5
10
0
0
SAD ENCODING
HAPPY
ENCODING
PLACEBO
ENCODING
DOPE ENCODING
Two Types of Context

Intrinsic context
– Has direct impact on the meaning of the tobe-remembered item
• strawberry-JAM vs. traffic-JAM

Extrinsic context
– Situation has indirect effect on the to-beremembered 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 YOU
SO 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

Not good
evidence
Patient K.C.
– Episodic memory processes
disrupted, but semantic memory
processes in tact
Good
evidence