1. Memory (1)

2. Atkinson & Shiffrin (1968) Model of Memory

3. Visual Sensory Store X M R J C N K P V F L B
It appears that our visual system is able to hold a great deal of information but that if we do not attend to this information it will be rapidly lost.
Sperling (1960)
Presented array consisting of three rows of four letters
Subjects were cued to report part of display
Demo at:
X M R J
C N K P
V F L B

4. Visual Sensory Memory Vary the delay of cue in partial report
After one second, performance reached asymptote
Mean number of words reported
Delay of cue (in seconds)

5. Iconic Memory
Sperling’s experiments indicate the existence of a brief visual sensory memory – known as iconic memory or iconic store
Information decays rapidly unless attention is transfers items to short-term memory
Analogous auditory store: echoic store

6. Atkinson & Shiffrin (1968) Model of Memory
Short-term memory (STM) is a limited capacity store for information -- place to rehearse new information from sensory buffers
Items need to be rehearsed in short-term memory before entering long-term memory (LTM)
Probability of encoding in LTM directly related to time in STM

7. a memory test... CONCRETE FOLDER DOORKNOB RAILROAD DOCTOR HAMMER
TURKEY
LETTER
SUNSHINE
KITTEN
PLAYER
MAPLE
CANDLE
TABLE
SUBWAY
PENCIL
SOFTBALL
TOWEL
COFFEE
CURTAIN

8. Serial Position Effects
no distractor task
distractor task
In free recall, more items are recalled from start of list (primacy effect) and end of the list (recency effect)
Distractor task (e.g. counting) after last item removes recency effect

9. Serial Position Effects
Explanation from Atkinson and Shiffrin (1968) model:
Early items can be rehearsed more often
 more likely to be transferred to long-term memory
Last items of list are still in short-term memory (with no distractor task)
 they can be read out easily from short-term memory

10. Forgetting over time in short-term memory.
Peterson and Peterson (1959)

11. Baddeley’s working memory system.
Baddeley proposed replacing unitary short-term store with working memory model with multiple components:
Phonological loop
Visuo-spatial sketchpad
Central executive (ignore the episodic buffer)
Baddeley and Hitch (1974)
Baddeley (1986)

12. Phonological Loop (a.k.a. articulatory loop)
Stores a limited number of sounds – number of words is limited by pronunciation time, not number of items
Experiment:
Word length effect – mean number of words recalled in order (list 1  4.2 words; list 2  2.8 words)
Phonological loop stores seconds worth of words
LIST 1:
Burma
Greece
Tibet
Iceland
Malta
Laos
LIST 2:
Switzerland Nicaragua Afghanistan Venezuela Philippines
Madagascar

13. Two routes to phonological loop
Articulatory control process
Visual presentation
Speech code
Phonological
loop
Auditory presentation
Articulatory control process converts visually presented words into a speech code
Articulatory suppression (e.g. saying “the” all the time) disrupts phonological loop
Prediction:
Word length effect depends on phonological loop
With articulatory suppression, visually presented items should not display word length effect

14. Immediate word recall as a function of modality of presentation (visual vs. auditory), presence vs. absence of articulatory suppression, and word length.
Baddeley et al. (1975).

15. Working memory and Language Differences
Different languages have different #syllables per digit
Therefore, recall for numbers should be different across languages
E.g. memory for English number sequences is better than Spanish or Arabic sequences
(Naveh-Benjamin & Ayres, 1986)

16. Evaluation of the Evidence for the Phonological Loop
Accounts for phonological similarity and the word-length effect
Support from neuroimaging studies
Baddeley, Gathercole, and Papagno (1998)
Its function may be to learn new words

17. Encoding & Retrieval Effects

18. Levels of Processing (Craik & Lockhart, 1972)
Levels of processing effect:
Deeper levels of processing (e.g., emphasizing meaning)
leads to better recall.

19. Encoding Specificity Principle
Recollection performance depends upon the interaction between the properties of the encoded event and the properties of the retrieval information

20. Context Change
Information learned in a particular context is better recalled if recall takes place in the same context
Similarly, information learned in a particular context may be difficult to recall in a dramatically different context

21. Godden & Baddeley (1975, 1980) Memory experiment with deep-sea divers
Deep-sea divers learned words either on land or underwater
They then performed a recall or recognition test on land or underwater

22. Mood-dependent Memory
Easier to remember happy memories in a happy state and sad memories in a sad state.
Subjects study positive or negative words in normal state. Test in positive or negative induced states.
 mood primes certain memory contents
Kenealy (1997).

23. State-dependent recall
Does physical state matter?
Eich et al. (1975): study while smoking normal or marijuana cigarette. Test words under same or different physical condition

24. Forgetting

25. Forgetting Functions
Ebbinghaus (1885/1913): Forgetting over time as indexed by reduced savings.
Most forgetting functions show:
Negative acceleration
Rate of change gets smaller and smaller with delay
Power law of forgetting

26. Forgetting Why do we forget? Some possibilities:
Memory has disappeared
 decay theory
Memory is still there but we can’t retrieve it
 repression
 inhibition theory
 interference theory

27. What is Repression?
“Something happens that is so shocking that the mind grabs hold of the memory and pushes it underground, into some inaccessible corner of the unconscious.” - Loftus (1993)
Some self-help book (“Courage to Heal”) relate repressed memories to sexual abuse

28. Recovered memory vs. False Memory
How do we know whether repressed memories are accurate?
In some cases, traumatic information is misremembered or simply “made up”
Loftus has been involved in many cases
Points out problems of
hypnosis
suggestive questioning
dream interpretations
Elizabeth Loftus

29. False Memory in the Lab SNORE NAP SLUMBER PEACE DROWSY YAWN BLANKET
Deese, Roediger, McDermott paradigm
Study the following words
Recall test ....
Recognition memory test Use ratings 1) sure new 2) probably new 3) probably old 4) sure old
TEST:
SNORE
NAP
SLUMBER
PEACE
DROWSY
YAWN
BLANKET
DOZE
SNOOZE
BED
AWAKE
REST
TIRED
WAKE
DREAM
SLEEP
COFFEE
SNORE
REST

30. Results
Critical lure (“sleep”) are words not presented but similar to studied words. These words are often falsely recalled (sleep: 61% of Ss.)
Recognition memory results
proportion of items classified with confidence levels:
confidence rating
studied items
not studied
unrelated
critical lure
(e.g. “REST”)
(e.g. “COFFEE”)
(e.g. “SLEEP”)

31. Subjects reporting recovered memories are more vulnerable to false memories
False recognition of words not presented in four groups of women with lists containing eight associates.
Clancy et al. (2000)

32. Proactive and retroactive interference

33. Inhibitory mechanisms in Forgetting
Cued recall as a function of the number of times the cues had been presented before for recall (respond condition) or for suppression (suppress condition).
Anderson and Green (2001)