1. Plans: Read About False Memories (Beth Loftus) for Thursday (April 7th) Read About Amnesia (Oliver Sacks) for Tuesday (April 12th) Read about Subliminal Messages (Vokey and Reed) for Thursday (April 14th)

2. Memory Short-Term “Working” Memory

3. Overview of Memory Atkinson-Shiffrin Model Sensory Signals Sensory Memory Short-Term Memory Long-Term Memory ATTENTION REHEARSAL RETRIEVAL

4. Short-Term Memory process by which we hold information “in mind”

5. Short-Term Memory process by which we hold information “in mind” example: temporarily remembering a phone number

6. Characteristics of STM Duration? Capacity? How could one measure these parameters?

7. Characteristics of STM Limited Duration –Brown-Petersen Task: subject is given a trigram (e.g. C-F-W) to remember vocal rehearsal is prevented by counting backwards recall accuracy tested as a function of retention interval

8. Characteristics of STM STM decays over seconds

9. Characteristics of STM Limited Duration –Brown-Petersen Task Interpretation: rapid loss of information in STM (over a period of seconds…much longer than sensory memory)

10. Characteristics of STM Limited Capacity –How might you measure capacity?

11. Characteristics of STM Limited Capacity –George Miller –Subject is given longer and longer lists of to- be-remembered items (words, characters, digits)

12. Characteristics of STM Limited Capacity –George Miller –Subject is given longer and longer lists of to- be-remembered items (words, characters, digits) –Result: Subjects are successful up to about 7 items

13. Characteristics of STM Limited Capacity –What confound must be considered ?!

14. Characteristics of STM Limited Capacity –What confound must be considered ?! –Recalling takes time !

15. Characteristics of STM Limited Capacity –What confound must be considered ?! –Recalling takes time ! –It seems that the “capacity” of STM (at least measured in this way) depends on the rate of speech - faster speech leads to apparently larger capacity –Some believe capacity is “2 - 3 seconds worth of speech”

16. Forgetting from STM Why do we “forget” from STM? –Does the memory trace decay? not likely because with very small lists (like 1 item) retention is high for long intervals

17. Forgetting from STM Why do we “forget” from STM? –Does the memory trace decay? not likely because with very small lists (like 1 item) retention is high for long intervals –Instead, it seems that information “piles up” and begins to interfere

18. Forgetting from STM Interference in STM is complex and specific

19. Forgetting from STM Interference in STM is complex and specific For example, severity of interference depends on meaning

20. Forgetting from STM Interference in STM is complex and specific For example, severity of interference depends on meaning –Subjects are given successive recall tasks with list items from the same category (e.g. fruits) –final list is of either same or different category - how is good is recall on this list?

21. Forgetting from STM Accuracy rebounds if category changes

22. Coding in STM How is information coded in STM?

23. Coding in STM Clues about coding in STM: –# of items stored in STM depends on rate of speech

24. Coding in STM Clues about coding in STM: –# of items stored in STM depends on rate of speech –phonological similarity effect: similar sounding words are harder to store/recall than different sounding words

25. Coding in STM Clues about coding in STM: –# of items stored in STM depends on rate of speech –phonological similarity effect: similar sounding words are harder to store/recall than different sounding words What does this suggest about the nature of information in STM?

26. Coding in STM It seems that information can be stored in a linguistic or phonological form

27. Coding in STM It seems that information can be stored in a linguistic or phonological form Must it be stored this way?

28. Coding in STM It is also possible to “keep in mind” non- verbal information, such as a map Are there two different STM systems?

29. A Modular Approach to STM Allan Baddeley: Articulatory Loop Central Executive Visuospatial Sketchpad In general, how can we know if there are one, two, or more independent systems handling some aspect of perception or cognition?

30. A Modular Approach to STM Double-Dissociation: Indicates that two processes or systems are independent

31. A Modular Approach to STM A dissociation occurs when one process is influenced by changing a variable but another process is not

32. A Modular Approach to STM A dissociation occurs when one process is influenced by changing a variable but another process is not A double-dissociation occurs when two different processes are influenced by changing two different variables

33. A Modular Approach to STM Performance Damage Sparkplugs Engine Radio Antenna

34. A Modular Approach to STM The logic of double-dissociation informs us about working memory modules

35. A Modular Approach to STM Articulatory Loop Central Executive Visuospatial Sketchpad Experiment 1 in the article by Lee Brooks demonstrates a double dissociation between Articulatory Loop and Visuospatial Sketchpad

36. Working Memory “Modules” Lee Brooks: interference between different representations in STM (Experiment 1) –Memory Representation verbal task: categorize words in a sentence spatial task: categorize corners in a block letter –Response Modality verbal response: say “yes” or “no” spatial response: point to “yes” or “no”

37. Working Memory “Modules” result: Performance Response Modality Verbal Spatial Spatial Representation (categorize corners) Verbal Representation (categorize words)

38. Working Memory “Modules” Interpretation: –supports notion of modularity in Working Memory (visuospatial sketchpad / articulatory loop)

39. Next Time: Long-Term Memory Read Loftus for Next Thursday