Transcript 7 - smw15.org

PSY 445: Learning & Memory
Chapter 7 Human Memory: Conceptual Approaches
Processes involved in retaining, retrieving, and using
information about stimuli, images, events, ideas, and skills
after the original information is no longer present
 Three theoretical approaches to memory
Memory components
 Different types of memory
Stages of memory
 Series of steps are involved in memory process
Processes of memory
 Emphasis is on how memories are processed
Why do we think there are multiple memory systems?
 General principles differ for STM and LTM
 Heuristic value – guideline that is fairly accurate
 Empirical evidence supporting the existence of multiple
processes
 Dissociation – occurs when an experimental variable
has different effects on different tasks
 Double dissociation – experimental variables
differentially affect performance on two or more tasks
Kesner, Hopkins, & Chiba (1992)
Procedure
 Group 1: Left-hemisphere brain damage
 Group 2: Right-hemisphere brain damage
 Words or an X was flashed on a screen
 Participants were asked to recall the word and the location of
the X
Results
 Group 1 did worse on the word-recognition test; Group 2 did
worse on the spatial-location test
Interpretation
 The two cerebral hemispheres are playing different roles in verbal
and spatial learning; double dissociation
Dual-Store Theory
 Short-Term Memory
 Long-term memory
Atkinson & Shiffrin (1968)
A limited capacity memory system involved in
the retention of information for brief periods; it
is also used to hold information retrieved from
long-term memory for temporary use
Duration of STM
 Without maintenance rehearsal something stays
in STM for between 15-30 seconds
Capacity of STM
 About 7 items

Differences in capacity
 STM is relatively small and easily measured
 LTM is immeasurable and probably limitless
 Differences in duration
 STM can hold only items briefly
 LTM are relatively permanent; not affected by the
passage of time much
 Evidence for the STM vs. LTM Distinction
 Serial-position curve results
Explicit memory
 Is long-term memory for factual knowledge and
personal experiences and requires conscious recall
Two types of explicit memories:
 Episodic memories are memories for personal life
experiences (e.g., your senior prom night)
 Semantic memories are memories for factual
knowledge that is true of everyone (e.g., the current
President of the United States)
Testing Episodic and Semantic Memories
Limitations
 It is difficult to differentiate episodic and semantic
memories in lab tests
 The two forms of memory require different testing
materials, procedures, or tasks
 Word-frequency effect is an example of this
See next slide 
Procedure
Group 1: given a test of episodic memory
 High-frequency and low frequency words are presented
to participants; later, word recognition test
Group 2: given a test of semantic memory
 High-frequency and low frequency words are presented
to participants; later strings of letters are briefly flashed
on the screen; task is to decide which strings form real
words and which do not
Results
 Group 1: More low-frequency words from original list are
recognized; this paradoxical result is referred to as the
Word-Frequency Effect
 Group 2: More high-frequency words from original list
are recognized
Interpretation
 Confounding of the type of test with the type of
memory
 Not necessarily testing episodic vs. semantic processes
but rather recognition memory vs. identification
memory
Implicit memory
• Long-term memory that influences our behavior, but
does not require conscious awareness or declarative
statements (e.g., for most adults, driving a car;
walking)
• Procedural memory is a type of implicit memory
See next slide 
The acquisition of knowledge of how to do things and
includes perceptual skills, motor skills, and cognitive skills
 Memory for highly practiced skills (often referred to as skill
memory)
 Bike-riding, Shoe-tying
Automatic or implicit nature to it (implicit memory)
 Do you think about reading a book?
 Do you think about riding your bike?
Mirror drawing 
The facilitated response to a stimulus that has been
recently experienced
 Occurs when the test stimulus is the same as or
resembles the priming stimulus
 The initial presentation of a stimulus affects subsequent
presentations
Rajaram & Roediger (1993)
Procedure
Word completion test
Phase 1: Present priming stimuli
• Example: table
Phase 2: Open-ended recall
• Example: Complete this word: tab___
Results
 Primed participants (49%) are more likely than non-primed
participants (30%) to use a particular word
Interpretation
 Participants responses are manipulated by implicit
processes
Warrington & Weiskrantz (1968)
Procedure
 Participants are patients with Korsakoff’s syndrome
(cannot form new LTMs);
 Researchers trained them to identify incomplete pictures
Subjects never remembered their previous days of training
Warrington & Weiskrantz (1968)
Results
 Performance improves even though the person does not
remember being trained
Results
Interpretation
 Priming can occur with pictorial stimuli as well; previous
experiences affect current behavior without awareness
3 stages of processing for manipulation of mental
representations:
Encoding (acquisition of info)
Storage (retention of info)
Retrieval (recovery of info)
STM 
Encoding/Failure
Retrieval? (LTM)
Retention
time
Dissociating Stages
 Experimental
 Neuropsychological
Experimental manipulations often detect
functional dissociations of the stages
 Encoding, storage, or retrieval may be affected
differently
 Different things are involved depending on the
stage of memory
Storm & Caird (1967): Experiment 1
Procedure
 Alcoholic inpatients were given lists to learn either while
sober or after consuming alcohol; both groups tested
later in sober state (two groups: S/S, A/S)
Results
 S/S outperforms A/S
Interpretation
 Alcohol impaired encoding
 However, alternative explanation is performance is
related to state-dependent retrieval
Storm & Caird (1967): Experiment 2
Procedure
 Two more groups were added (total of four groups now)
 Studied sober and tested when drinking alcohol (S/A)
 Studied when drinking alcohol and tested while drinking alcohol
(A/A)
Results
 S/S > A/A
Interpretation
 More than just retrieval failure; due to impaired encoding
Neuropsychologists attempt to
dissociate certain stages by
finding individuals with
impairment at one stage or
another
Hippocampus: brain structure
plays a key role in allowing us to
store new information
The classic case of H.M. who had
this part of brain removed
In 2008 (at the time of his death at
age 82), was his name revealed as
Henry Molaison 
The man who keeps falling in love with his wife
 Another case study is Clive Wearing who suffered severe brain
damage to the hippocampal area after contracting viral
encephalitis
 Lives completely within the last 1-2 minutes
Click on picture for media report 
Click on picture for
videos 
Clive Wearing
(77 years old)
From neuropsychological dissociation view, H.M.’s
problem could be explained in several ways:
 Encoding deficit
 Storage deficit (encoding okay)
 Retrieval deficit (encoding and storage okay)
Craik & Lockhart (1972)
 A single memory system is hypothesized
 Rapid forgetting is due not to a loss from
transient STM but rather because of shallow
processing
 Retention is due not to transfer from one
memory store to another, but rather to deeper
processing
How does storage of information take place?
 Maintenance Rehearsal
▪ Repeating things over and over
▪ Spacing effect
 Elaborate Rehearsal
▪ Involves thinking about how new material relates to
information already stored in memory

Shallow Processing
 Little attention to meaning
 Focus on physical features of the word (number of
vowels, letters in all capitals)
 Occurs during maintenance rehearsal

Deep Processing
 Close attention to meaning
 Relating item to something else
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Craik & Tulving (1975)
Procedure
Recall Test was a surprise to participants
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Procedure
Types of questions
 Shallow:
 Is the word printed in capital letters?

Deeper:
 Does the word rhyme with train?

Deepest:
 Does the word fit into the sentence “He saw a ____ on
the street?”
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Results
Craik & Tulving (1975)
Shallow:
Deeper:
Deepest:
• Deep processing takes longer but results in better memory
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Interpretation
 Memory for words is better when they are linked
to other knowledge
Craik & Tulving (1975)
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Depletion of Memory Capacity


When participants are attempting to perform two cognitive
tasks at once, (for example, doing math calculations and
remembering words), if the primary task requires deeper
processing, this leaves little left over for the other task
Deeper processing on the first task is shown by poor
performance on the second task
Semantics Issue


The term “depth” appears to be taking on different
meanings
Elaboration of an item in memory or more distinctive
representation in memory
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Morris, Bransford, & Franks (1977)
 Similarity between encoding and retrieval conditions
 During retrieval, we need to reinstate the cognitive
operations that were used at encoding
 Explicit memory: match mental operations of
encoding and retrieval
 Implicit memory: match perceptual operations at
encoding and retrieval
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Weldon & Roediger (1987)
Procedure
 Phase 1:Students studied lists of both pictures and words
 Phase 2: Either a picture fragment or word-completion test
was given
 Task for both groups was to name the picture or word
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Weldon & Roediger (1987)
Results
 Studying pictures produced more priming than did words on
a picture-fragment test; studying words produced more
priming than did pictures on the word-fragment test
Results 
36
Interpretation
 Transfer-appropriate processing was necessary for
optimal recall to occur
Picture-fragment test: inspecting a picture is similar at
both encoding and at retrieval; dissimilar to wordreading
 Word-fragment test: Reading words is a cognitive
operation similar to completing words, but inspecting
pictures is not

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Simulate various memory phenomenon by using
a network of hypothetical neurons
 Attempt to statistically model the nervous
system on a computer
 Each neural unit can potentially have
connections to many other units; the more
connections the better memory
Modeling Person Identification
 Many possible connections between names and
identities
For example, John has a connection
to several potential features 
The Delta Rule
 Connections can vary in strength
 Mathematical formula used for increases and
decreases in strength
Classification of Amnesias
Two dimensions


Cause: physical or psychological (psychogenic amnesia)
Time: loss of memory preceding (retrograde) or following the
trauma (anterograde)
Retrograde amnesia
•
Loss of memory for events that have happened prior to trauma or
disease
Anterograde amnesia

The inability to form long-term memories for events following
brain surgery or trauma
 Retrograde amnesia—TRAUMA—Anterograde amnesia 
Amnesias caused by psychological traumas are almost
retrograde
Psychogenic Amnesia
3 main categories:
Limited Amnesia
 Forgetting of a specific traumatic experience
Fugue state
 Loss of one’s entire past life and identity; often travel
away from home
Dissociation Disorder
 A person exhibits multiple personalities or identities
ABC News Poll (1997)

46% more worried about failing memory than
failing health
Plethora of self-help books, websites, and herbal
medications
 Most worry is unjustified
Some of the slides in this presentation prepared with the assistance of the
following website:
 www.csupomona.edu/.../PSY335%20PPTs/Baddeley/BChap6....