Transcript Memory_partIII - UCI Cognitive Science Experiments

Memory Part III
Encoding & Retrieval
Exceptional Memory
Overview
• Causes of Forgetting
• Interactions between encoding and retrieval
• Exceptional memory performance
State theory of memory
Rehearsal
Sensory
Memory
Decay
Attention Short-term
Memory
Response
Encoding
Retrieval
Long-Term
Memory
Causes of forgetting
• Inadequate encoding – information is not
attended to or is not transferred to LTM
• Decay – memory traces decay in strength over
time
• Interference – memories learned before or after
some given memory interfere with retrieval
• Distortion– memories are modified over time
Causes of forgetting
• Inadequate encoding – information is not
attended to or is not transferred to LTM
• Decay – memory traces decay in strength over
time
• Interference – memories learned before or after
some given memory interfere with retrieval
• Distortion– memories are modified over time
Decay
• The longer the retention interval (time between
learning and retrieval) the greater the chance of
forgetting
Ebbinghaus (1885-1913)
Reminiscence Bump
Typically, everyday
memory follows
Ebbinghaus’ retention
function
Exception: enhanced
memory for events during
adolescence & young
adulthood.
Schrauf & Rubin (1998)
Causes of forgetting
• Inadequate encoding – information is not
attended to or is not transferred to LTM
• Decay – memory traces decay in strength over
time
• Interference – memories learned before or after
some given memory interfere with retrieval
• Distortion– memories are modified over time
Interference
• “Memories interfering with memories”
– Book calls this effect of “new learning”
• Caused by one memory competing with or replacing
another memory
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Interference from intervening events
• Experiment: ask for recall of previous teams played
Retrieval failures
• Forgetting can occur when the wrong retrieval cues are
used
• Context reinstatement
• Cues are useful if they re-create the context in which
the original learning occurred
• allows the person to use retrieval paths.
Context Reinstatement
Memory experiment with deep-sea divers
– Deep-sea divers learned words either on land or underwater
– They then performed a recall test on land or underwater
Godden & Baddeley (1975, 1980)
State-dependent memory
• Memory is enhanced if people learn and recall
information in the same physical state
Emotional State-Dependent Memory
90
1. Learn 16 words when happy
2. Placed in happy or sad
mood.
3. Asked to recall words
80
Percent Recalled
Learn 16 words when sad
Learn Happy
Learn Sad
70
60
50
40
30
Recall Happy
Recall Sad
Kenealy (1997).
State-dependent recall
• Study while smoking normal or marijuana cigarette. Test
words under same or different physical condition
(Eich et al. 1975)
Encoding Specificity Principle
• Context reinstatement effects can be explained by
encoding specificity principle:
• Recollection depends on the interaction between the
properties of the encoded event and the properties of the
retrieval information
The Spacing Effect
• Spacing effect: Memory is better for repeated information
if repetitions occur spaced over time than if they occur
massed, one after another
Spacing Effects
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Spaced repetitions better for long term retention.
Massed better for short term retention.
Explaining Spacing Effects
• Studying material on different occasions (spacing) leads
to different encodings of the same material
• Because spacing increases encoding variability, there
are more ways in which information can be accessed
and retrieved at test
Exceptional Feats of Memorization
• Cases where people do not forget anything
Patient S
• Described in Luria (1975): “The mind of a mnemonist”
• “virtually limitless’ memory”
• But could also not forget irrelevant details: bad at
inductive reasoning (‘filling in the blanks’)
Daniel Tammet
• Described in book “Born on a blue day”
• Aspergers syndrome
• Has capability of synesthesia
Video (~7 min.)
Available on YouTube: http://youtu.be/Xd1gywPOibg
Superior Autobiographical Memory
• Recently, James McGaugh at UC Irvine discovered
individuals with extreme autobiographical memory
• Individuals are “normal”
– are not autistic
– not synesthetes
– do have some enlarged brain areas
James McGaugh
Video
Video available at: http://www.cbsnews.com/video/watch/?id=7166313n&tag=topnews
Also watch part 2: http://www.cbsnews.com/video/watch/?id=7166315n&tag=contentBody;housing