Transcript Lecture_02

Lecture 2 – Psyco 350, A1
Winter, 2011
N. R. Brown
Psyco 350 Lec #2 – Slide 1
Outline
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A Little History
Information Processing & the Modal Model
Memory Systems
Aspects of Modal Model:
– STM vs LTM: Serial Position Curve
– Properties of STM
• Capacity: Span Task
• Duration/Forgetting: Brown Peterson Task
• Retrieval: Sternberg Task
Psyco 350 Lec #2 – Slide 2
A Very Little Bit of History
Psyco 350 Lec #2 – Slide 3
Hermann Ebbinghaus (1850-1909)
• Father of Memory
Research
• Memory stripped of
meaning
• Inventor of the nonsense
syllable (DAX, FOZ, KIR)
• Discoverer of:
– Learning curve
– Forgetting function
Psyco 350 Lec #2 – Slide 4
Fredrick Bartlett (1850-1909)
• Impact of prior
knowledge and meaning
on memory.
• Most important ideas:
– reconstruction
– schemata
Psyco 350 Lec #2 – Slide 5
Verbal Learning
• Emerged from Behaviorism
• Focus:
– relationship between external variables and
human memory performance
– forgetting and theories of forgetting
• Approach:
– Rigorously conducted, list learning (often paired
associate) experiments
Psyco 350 Lec #2 – Slide 6
Historical Precedence
Ebbinghaus
Verbal
Learning
Behaviorism
Contemporary
Memory
Research
Bartlett
Information
Processing
Cog Psych
Psyco 350 Lec #2 – Slide 7
And Now …
Cognitive
Research
Memory
Research
Psyco 350 Lec #2 – Slide 8
Information Processing 
• Core metaphor:
human mind as serial computer
• To understand/describe computer behavior,
specify:
– hardware
– software
– available data
Psyco 350 Lec #2 – Slide 9
Information Processing
To understand/describe human behavior, specify:
• the cognitive architecture (hardware)
– identify components & their general function:
– characterize components in terms of:
• capacity
• speed
• accuracy
• a cognitive task analysis (software & data)
Psyco 350 Lec #2 – Slide 10
Information Processing
Cognitive Task Analysis (software & data):
• What are the mental operations required to perform a
task?
• How are the operations sequenced?
• What information is involved in task?
• How is the information accessed?
• How is it represented?
• How is it altered during the processing?
Psyco 350 Lec #2 – Slide 11
A Simple Computer Architecture
• Input
devices/registers
• Active memory and
processing
• Inactive (but
accessible) memory
Psyco 350 Lec #2 – Slide 12
Modal Model of Memory
• The standard model of memory
• Atkinson & Shiffrin (1968)
• Four components
– Sensory registers
– Short-term memory
– Long-term memory
– Control processes
Psyco 350 Lec #2 – Slide 13
Modal Model of Memory
Psyco 350 Lec #2 – Slide 14
Psyco 350 Lec #2 – Slide 15
Psyco 350 Lec #2 – Slide 16
Psyco 350 Lec #2 – Slide 17
Modal Model: Component Functions
1. Sensory stores:
function: buffers sensory input for selection and identification
2. Short-term Memory
function: temporal storage during processing
3. Long-term Memory
function: store declarative & procedural knowledge
declarative -- knowing that
procedural -- knowing how
4. Attention
function: Selection and transfer from sensory stores
Maintenance of information in STM
Selection and scheduling of tasks
Psyco 350 Lec #2 – Slide 18
Multiple (Long-term) Memory Systems
• Long-term memory involves several subcomponents
• Different memory systems for different types of
information
Psyco 350 Lec #2 – Slide 19
Multiple Memory Systems
• Memory
– Declarative Memory (explicit memory)
• Semantic memory
–“permanent,” decontextualized knowledge
• Episodic memory
–“forgettable” event memories
– Nondeclarative memory (implicit memory)
• Procedural memory
• Classical conditioning
• Priming
Psyco 350 Lec #2 – Slide 20
Memory as Everything – A Simple Demonstration
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(read &) store 1st #:
(read &) store 2nd #:
Retrieve-execute:
retrieve top ones digit:
retrieve bottom ones digit:
retrieve addition fact:
store ones sum:
retrieve-execute:
– retrieve top tens digit:
– retrieve addition fact:
– store new top tens digit:
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retrieve top tens digit
retrieve bottom tens digit:
retrieve addition fact:
store tens sum
Retrieve, combine sums
State answer:
Psyco 350 Lec #2 – Slide 21
[84]
blue = WM
[57]
[2-digit addition strategy] red = procedural
[4]
memory
[7]
[4+7=11]
green = semantic
[1]
memory
[carry operation]
[8]
[8+1=9]
[9]
[9]
[5]
[9+5=14]
[14_]
[14; 1  141]
“141”
Modal Model: Evidence STM – LTM Distinction
• Assumption:
– dual stores – STM & LTM:
• small amount of info held briefly in STM
• rehearsal enables and is required for transfer
from STM to LTM
• Support: serial-position-curve phenomena
Psyco 350 Lec #2 – Slide 22
Free Recall & the Serial Position Curve
Memory
Tests
Recall
Cued
Uncued
Serial
Psyco 350 Lec #2 – Slide 23
Recognition
FREE
Free Recall Task
Instructions:
There are 15 words on this list.
When I say to, please write down as many of
these words as you can.
List #1 – 15 words
Psyco 350 Lec #2 – Slide 24
Free Recall Task
Instructions:
There are 15 words on this list.
When I say to, please write down as many of
these words as you can.
List #2 – 15 words; 20 s delay
Psyco 350 Lec #2 – Slide 25
Free Recall & the Serial Position Curve
• Free recall:
– uncued recall of studied items
– order of output unconstrained
• Manipulate a variety of:
– Encoding factors (e.g. presentation rate)
– Storage factors (e.g., delay)
• Dependent variable:
– % recalled as a function of serial position
Psyco 350 Lec #2 – Slide 26
Serial Position Curve
• Primacy: Good recall for 1st few items
• Recency: Good recall for last few items on list
Psyco 350 Lec #2 – Slide 27
Modal Account of the Serial Position Curve
• Recency Effect produced by read-out from
STM
• Primacy & “pre-recency” reflect information
retrieved from LTM
• “Transfer” from STM to LTM caused by
rehearsal.
• Implications:
– Primacy & Prerecency:  w/ rehearsal
– Recency: unaffected by rehearsal
Psyco 350 Lec #2 – Slide 28
Rundus (1971):
Rehearsal & the Serial Position Curve
• Materials
– 20-word list
– presentation rate: 5 s/word
• Task(s):
– During study – overt rehearsal
– During test – free recall
Psyco 350 Lec #2 – Slide 29
Rundus: Rehersal Protocols
Psyco 350 Lec #2 – Slide 30
Relation between Rehearsal & Recall
• Analysis:
– # rehearsals for each
word (position)
– % recall for each word
(position)
• Results:
– “For a given amount of
rehearsal, items from the
initial serial positions are
no better recalled than
items from the middle of
the list” – Rundus, 1971,
p. 66
Psyco 350 Lec #2 – Slide 31
Relation between Study-time (Rehearsal) & Recall
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• Glanzer & Cunitz
(1966)
• manipulate studytime.
• Assume: study time
& rehearsal related
• Results:
– Primacy & Prerecency: 
w/ study time
– Recency: unaffected by
rehearsal
Psyco 350 Lec #2 – Slide 32
Relation between Filled Delay & Recall
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• Glanzer & Cunitz
(1966)
• Manipulate retention
interval.
• Assume filled delay
replaces contents of
STM
• Results:
– Primacy & Prerecency:
un affected by delay
– Recency  as delay 
Psyco 350 Lec #2 – Slide 33
Amnesia & Serial Position
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Psyco 350 Lec #2 – Slide 34
• Baddeley & Warrington
(1970)
• H.M. – removal temporal
lobe and hippocampus
• Clobbered Explicit
memory.
• Yet – on immediate test,
recency intact
Dissociation: Evidence for Dual Store
• Dissociation – when “a single variable has different affects on
two or more measures.”
• Evidence for separate stores, processes, or representation.
• Many variables have dissociative effect on the prerecency &
recency portion of serial position curve.
Study time
Post-list distraction
Ant. Amnesia
List Length
Word Frequency
Psyco 350 Lec #2 – Slide 35
Prerecency Recency
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