Memory
• Definition: Persistence
of learning over time
• The word “memory” is
derived from the ancient
Greek myth of
Mnemosyne, the mother
of the Muses, who was
“said to know
everything, past,
present, and future.”
Memory Extremes
• Memory Loss - The
cases of H.M. and Clive
Wearing
Supernormal Memory
• Photographic Memory The Case of S.
(Solomon V.
Shereshevskii); Luria
(1968) “The Mind of a
Mnemonist”
• Hyperthymesia – case
of H.K.
Memory Processes
“Memory” R. Magritte
Memory Involves 3 Stages of
Information Processing
• Encoding
• Storage
• Retrieval
Dualist Theories of Memory
• William James –
“Primary” and
“Secondary” memory
• Waugh & Norman
(1965)
• Atkinson-Shiffrin
(1971)
Atkinson & Shiffrin Modal Model
3 memories:
Sensory
STS
LTS
Information Flow Between
Memory Systems
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Sensory-STS
Sensory-LTS
STS-LTS
LTS-STS
Characteristics
• Structural storages
• Control processes
• Information loss and decay
e.g., Ebbinghaus Curve
Evidence for Dualist Theories:
Serial Position Curve
Short-Term (STM) or
Working Memory
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A temporary storage of information
Central to most cognitive activities
Identified with consciousness?
Memory workspace handles most of our
complex intellectual activities
• Freud - "Mystic Writing Pad"
Classic Research on Working
Memory: Capacity Issues
Memory Span
• Number of items in a
row that can be recalled
• Ebbinghaus tradition
• "digit span task"
Miller (1956) - Magical Number
Seven, Plus or Minus 2
• Chunk - basic unit of
memory storage in STM
• Chunking
• FBIJFKYMCAIRS
• FBI JFK YMCA IRS
Number of Items, or Amount of
Information?
• Alvarez & Cavanagh (2004) – complexity of
objects determines how much is stored
Brown - Peterson (1958; 1959)
Distracter Task
• Examined forgetting in
STM
• S's study 3 letters A Z
M - then given a
number (453) and count
backwards by 3
Coding Information into
Working Memory
Auditory Code
• Conrad (1963) study on letter recall
• e.g., similar sounding letters difficult to recall
• e.g., C, V, P (B,D given as errors)
Pronunciation Code
• a limit in terms of # items pronounced within
1.5 sec
• e.g., cat, dog, car, red, bed, wall
• synthesizer, crabcake, kangaroo, marvelous
Visual Code
• Posner & Keele (1967) letter matching
experiment
• AA – visual match
• Aa – name match
Semantic Code
• Wickens et al. (1976)
• PI (Proactive Inhibition) - previously learned material
interferes with new learning
• Release from PI - if the category of items shifted,
then memory goes up again
– Broccoli, Onion, Pepper
– Tomato, Lettuce, Radish
– Asparagus, Cauliflower, Cabbage
– Rose, Daisy, Tulip
Retrieval from Working Memory
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Sternberg (1969, 1975)
P given memory set (1 or 3 digits)
P given memory probe digit
RT decision as to whether probe digit is in memory
set
• Possibilities:
– Parallel scan
– Serial scan
• Self-terminating
• Exhaustive
Baddeley’s Model of
Working Memory
• Working memory viewed as having a number
of components (Baddeley, 1986)
• Viewed as a workbench where information is
temporarily held, manipulated and utilized
during cognitive tasks
4 Components
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Phonological Loop
Visuospatial Sketch Pad
Episodic Buffer
Central Executive
Phonological Loop
• Items stored in terms of how they are
articulated - related to sound
• Phonology - linguistic description of speech
sounds
• Phonological loop is limited; memory trace
decays within 2 sec
• Imaging studies: left frontal and temporal
lobes activated; parietal lobe
Visuospatial Sketchpad
• Visual and spatial information is stored
• Limited-capacity
• Imaging studies: right hemisphere; occipital
lobe; frontal lobe
Episodic Buffer
• Temporary store where info from phonological
loop, visuospatial sketchpad, and long-term
memory can be stored
• Limited capacity
Central Executive
• Is a supervisor; integrates information across
phono loop, sketchpad, and episodic buffer
• Coordinates strategies of information coding
into and out of WM
• Allocates capacity to appropriate processes
• Coordinates transfer in and out of LTM
• Imaging studies: frontal lobe
Cognitive Neuroscience of
Working Memory – Case Studies
• Milner (1966) – case of H.M.
– Hippocampus involved
• Warrington & Shallice (1969) – case of K.F.
Prefrontal Cortex
• Appears to be involved in maintaining
information in working memory
• Primate research – delayed response memory
task data
• Infants – object permanence around 8 months
• Other areas such as visual cortex, etc. also
involved
• Seems to be a distributed function