Contents
1. Primary Memory
① Broadbent’s Model
② Waugh and Norman’s Model
③ Atkinson and Shiffrin’s Dual-Store Model
2. The Serial Position Curve and the
Modal Model
3. Problems with the Modal Model
① Continual distractor paradigm
② Ratio rule
③ Changing distractor effect
4. Summary of the Modal Model
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1. Primary Memory
Dividing memory into multiple stores
One store specialized for briefly holding information : primary memory, working memory, short-term memory and short-term store. Computer mataphor of memory
The resultant of two-store conception of
memory :
(1974))
Modal Model (termed by Murdock
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1. Primary Memory
① Broadbent’s Model
Human processor as a series of systems
through which information flows
S-system : a preattentive sensory store, the
forerunner of iconic and echoic memory
P-system : the site of awareness, limited capacity store
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1. Primary Memory
① Broadbent’s Model
Three assumptions of Broadbent’s
view
1) Primary and secondary memory involve
separate memory systems.
2) Primary memory has a limited capacity.
3) Because information fades quickly in primary memory, information is retained only when it is actively rehearsed.
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1. Primary Memory
① Broadbent’s Model
“The Magical Number Seven, Plus or
Minus Two” [George Miller (1956)]
Absolute identification experiment
Hear a set of nine tones that vary only in frequency On each trial, one of these tones is played, then tries to identify it.
The subject is informed whether the response is correct and, if not, what the correct response should have been.
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1. Primary Memory
① Broadbent’s Model
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1. Primary Memory
① Broadbent’s Model
Generally speaking, once the number of
items reaches about eight or nine, subjects become unable to perform the task without errors
When stimuli vary along more than one
dimension, identification is much better.
Ex) 26 letters of the alphabet
A a
Bb Cc Dd Ii
O o ….
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1. Primary Memory
② Waugh and Norman’s Model
• Perceived information first enters primary
•
•
•
•
memory, a limited capacity structure
Some information is lost by displacement, as newly arriving items “bump out” already existing items. Other information might be rehearsed and thus remain in primary memory longer.
Rehearsal also caused the information to be transferred to secondary memory, which has no capacity limitation.
Recall can be based on information in primary 9
1. Primary Memory
③ Atkinson and Shiffrin’s Dual-Store Model
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1. Primary Memory
③ Atkinson and Shiffrin’s Dual-Store Model
• Assumed that transfer began and
continued during the entire time an item was in STS.
• Experiment [ Hebb (1966) ]
• Presented a series of nine-item lists to 40 subjects. • The lists were made up of the digits 1-9, presented in random order, and the task was recall the items in order.
• Most of the lists contained novel orderings, but
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one list was repeated every third trial.
1. Primary Memory
③ Atkinson and Shiffrin’s Dual-Store Model
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2. The Serial Position Curve and the Modal Model
Many experiments that tested
predictions of the modal model concerned the serial position function observable with free recall.
Murdock(1962) reported a free recall
experiment in which he presented lists of items that varied in length.
Lists of 10, 15, and 20 items.
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2. The Serial Position Curve and the Modal Model
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2. The Serial Position Curve and the Modal Model
Recency effect : excellent recall of the
last few items
Due to the dumping of items from STS
Primacy effect : batter recall of the first
few items
Due to the extra rehearsal the first few items
get, which copies them into LTS
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2. The Serial Position Curve and the Modal Model
• A strong prediction of the model is that if
recall is delayed, the primacy effect should remain unaltered but the recency effect should disappear.
• To test this prediction, Glanzer and
Cunitz(1966) presented 15-item lists to subjects. • In the control