1. PSY 445: Learning & Memory Chapter 7 -
Human Memory: Conceptual Approaches

2. Memory
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

3. Partitioning Memory 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

4. Double Dissociation 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

5. Components of Memory Approach
Dual-Store Theory
Short-Term Memory
Long-term memory
Atkinson & Shiffrin (1968)

6. Short-Term Memory (STM)
Psychology 101 On Line
Short-Term Memory (STM)
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 seconds
Capacity of STM
About 7 items

7. STM vs. LTM 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

8. Divisions of LTM 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)

9. Divisions of LTM 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 

10. Neely (1989) 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

11. Neely (1989)
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

12. Divisions of LTM 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 

13. Procedural Learning
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 

14. Repetition Priming
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

15. Repetition Priming 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

16. Divisions of LTM: Visual Object Priming
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

17. Divisions of LTM: Visual Object Priming
Results
Performance improves even though the person does not remember being trained
Interpretation
Priming can occur with pictorial stimuli as well; previous experiences affect current behavior without awareness
Warrington & Weiskrantz (1968)
Results

18. Stages of Memory Theory: Series of steps are involved in memory process
3 stages of processing for manipulation of mental representations: Encoding (acquisition of info) Storage (retention of info) Retrieval (recovery of info)
Encoding/Failure
Retrieval? (LTM)
STM 
Retention
time

19. Stages of Memory
Dissociating Stages
Experimental
Neuropsychological

20. Experimental Dissociations
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

21. Experimental Dissociations
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

22. Experimental Dissociations
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

23. Neuropsychological Dissociations
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 

24. Neuropsychological Dissociations
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)

25. Processing Approaches: Depth of Processing
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

26. Storage 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

27. Depth of Processing Shallow Processing Deep 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

28. Experimental Evidence for DOP
Craik & Tulving (1975)
Procedure
Recall Test was a surprise to participants

29. Experimental Evidence for DOP
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?”

30. Experimental Evidence for DOP
Results
Craik & Tulving (1975)
Shallow:
Deeper:
Deepest:
Deep processing takes longer but results in better memory

31. What DOP tells us? Interpretation
Memory for words is better when they are linked to other knowledge
Craik & Tulving (1975)

32. Depth of Processing: Limitations
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

33. Processing Approaches: Transfer Appropriate Processing
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

34. Processing Approaches: Transfer Appropriate Processing
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

35. Processing Approaches: Transfer Appropriate Processing
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. Processing Approaches: Transfer Appropriate Processing
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 word-reading
Word-fragment test: Reading words is a cognitive operation similar to completing words, but inspecting pictures is not

37. Connectionist Models
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

38. Connectionist Models Modeling Person Identification
Many possible connection between names and identities
For example, John has a connection to several potential features 

39. Connectionist Models The Delta Rule Connections can vary in strength
Mathematical formula used for increases and decreases in strength

40. The Study of Abnormal Memory: Amnesia
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

41. Types of Amnesias
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

42. Everyday Forgetting
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

43. Credits
Some of the slides in this presentation prepared with the assistance of the following website: