1. PSY 368 Human Memory Memory Implicit memory

2. Outline Theories accounting for Implicit vs. Explicit memory Experiment 2 Signal detection analysis Process-dissociation procedure, working through our example (probably not time, so after break)

3. Memory Tasks indirectdirect incidental implicit memory expts. Levels of Processing expts. intentional ?explicit memory expts. Test Instructions Study Instructions Implicit Memory : Often defined as "memory without awareness” Also “Non-declarative” & “procedural” (Squire, Knowlton, & Mesen, 1993)

4. Implicit/Explicit Dissociations Many demonstrations of different effects depending on whether implicit or explicit tasks are used Amnesic patients Levels of processing manipulations Pleasantness vs. vowel comparisons Generation effect Divided attention Picture-word superiority Note. Most of we’ve talked about concern repetition priming effect (study “horse” and respond “horse”)

5. Four major approaches have been proposed The Activation view Multiple Memory systems view Transfer appropriate processing view Bias View Accounting for Implicit/Explicit Dissociations

6. Four major approaches have been proposed The Activation view Multiple Memory systems view Transfer appropriate processing view Bias View Accounting for Implicit/Explicit Dissociations

7. The Activation View Priming on indirect tests is attributable to the temporary automatic activation of preexisting representations. Because it is automatic, it occurs without elaborative processing and thus has little to no contextual information Weak Point Can not explain priming over long time periods Some implicit priming over days or even weeks (e.g., Sloman, et al, 1988) Can not explain priming without pre-existing representations The least popular of the four views

8. Four major approaches have been proposed The Activation view Multiple Memory systems view Transfer appropriate processing view Bias View Accounting for Implicit/Explicit Dissociations

9. Multiple Memory Systems Many dissociations between direct and indirect tests of memory arise because the tests tap different underlying memory systems. Squire (1987)

10. Multiple Memory Systems Many dissociations between direct and indirect tests of memory arise because the tests tap different underlying memory systems. Tulving (1984)

11. Multiple Memory Systems What is a system? It is NOT a process It is NOT a task Some different ways that systems have been defined Schacter and Tulving (1994)

12. Multiple Memory Systems What is a system? Functional Dissociations Task that taps into system A that has no effect (or a different effect) in System B Different neural substrates System A involves different brain areas than System B (brain damage cases and neural imaging studies) Stochastic independence Performance on System A task uncorrelated with performance on a System B task Functional incompatibility Could involve different rates of forgetting Function carried out by System A can not be done by System B Schacter and Tulving (1994)

13. Multiple Memory Systems What is a system? Schacter and Tulving (1994) SystemOther NameSubsystemsCharacteristics ProceduralNondeclarativeMotor skillsNon-conscious operation (indirect) Cognitive skills Simple conditioning Simple associative learning Perceptual representation NondeclarativeVisual word form Auditroy word form Structural description Primary memory Working memoryVisualConscious operation (direct) Auditory SemanticGenericSpatial FactualRelational Knowledge EpisodicPersonal Autobiographical Event memory If you “know how to do something” Allows you to automatically recognize things See earlier in the semester Factual information (chpt 10) Memory of events

14. Brain areas Brain imaging studies found that different areas of the brain are used when completing implicit and explicit tasks Note: more than one structure involved in each type of memory Buckner et al (1995) PET study Multiple Memory Systems

15. Brain areas Brain imaging studies found that different areas of the brain are used when completing implicit and explicit tasks Gabrieli et al (1995) Case study of MS MRI of MS’s brain Intact performance on explicit tests of recognition and cued recall Intact performance on implicit test of conceptual memory Impaired performance on implicit tests of visual perceptual memory Suggests a specific deficit in visual implicit memory Studied lists of words Perceptual identification and recognition task Multiple Memory Systems

16. Brain areas Different kinds of implicit tasks seem to involve different areas Perceptual vs. conceptual tasks appear to use different brain areas Conclusion: brain area involvement may be a function of type of processing and type of memory Buckner & Koutstall (1998) fMRI study Multiple Memory Systems

17. Stochastic Independence Hayman and Tulving (1989) Measure correlation between explicit and implicit task performance If not correlated (independent), then tasks measure different processes Multiple Memory Systems Forgetting Tulving et al. (1989) showed a difference in forgetting rate for recognition and fragment completion Confirmed with other tasks (stem completion)

18. Strengths Fits well with dissociations found In patients In experiments Multiple Memory Systems Problem Hard to find consensus on what the systems are May be “too easy” to posit a new system

19. Four major approaches have been proposed The Activation view Multiple Memory systems view Transfer appropriate processing view Bias View Accounting for Implicit/Explicit Dissociations

20. The key to good performance is similarity of processes involved in encoding vs. retrieval, be it implicit or explicit, perceptual or conceptual test Implicit and explicit may refer to different processes, yet the key to performance is matching processes. Processes at encoding Processes at test Overlap determines retrieval success Transfer Appropriate Process A consequence: conceptual processing is the common core in free recall and implicit conceptual tasks, hence performance on these two types of task should be equal.

21. Transfer Appropriate Process Assumes: Performance depends of match between processing at study and processing at test. Analogous to encoding specificity. Two-types of Processes (Jacoby, 1990) Data-driven (perceptual) – processing of physical features. Conceptually-driven (semantic) – processing for meaning Typically confounded, however, it is possible to un- confound test-type from process-type

22. Jacoby (1990) proposed that implicit vs. explicit memory is confounded with two different kinds of memory processes (associated with two kinds of information) Mixing Implicit and Explicit Effects Memory system Mode of Processing Declarative (Episodic) Procedural (Priming) Perceptual (Data-driven) Perceptual identification Word Fragment Completion Meaning based (conceptually-driven) Free Recall Recognition

23. Data-driven (Perceptual): fragment completion stem completion anagram completion lexical decision perceptual identification Conceptually-driven (Semantic): word association doctor  ?? category-instance generation “ name a mammal ” general knowledge “ The capital of the US is …? ” Transfer Appropriate Process

24. Goal to demonstrate data-driven processing can affect direct tests data-driven processing do not necessarily affect indirect tests Blaxton (1989) Transfer Appropriate Process Data-drivenConceptually-driven DirectGraphic-cued Recall Free Recall IndirectFragment Completion General Knowledge

25. Target word: bashful graphic-cued recall: looks like “ bushful ” free recall frag completion: b_sh_u_ General knowledge: “ Name one of the 7 dwarfs ” Blaxton (1989) Data-drivenConceptually-driven DirectGraphic-cued Recall Free Recall IndirectFragment Completion General Knowledge Transfer Appropriate Process S’s saw or heard lists of words (key IV here)

26. Predictions Systems view : modality match should affect only indirect tests (if indirect tap separate system, then modality should affect them in the same way) for both implicit tests: visual > auditory for both explicit test: visual = auditory Blaxton (1989) Transfer Appropriate Process Data-drivenConceptually-driven DirectGraphic-cued Recall Free Recall IndirectFragment Completion General Knowledge Same pattern of results regardless of modality Visual better than auditory for both

27. Predictions TAP View : modality match should affect data-driven tasks only. (priming depends on match between study/test processing match & not on indirect vs direct): for both data-driven tests: visual > auditory for both conceptually-driven tests: visual = auditory Blaxton (1989) Transfer Appropriate Process Data-drivenConceptually-driven DirectGraphic-cued Recall Free Recall IndirectFragment Completion General Knowledge Visual should be better than auditory Visual and auditory should be about the same

28. Results Priming Effect (V > A) for data- driven tasks only: indirect : frag completion direct : graphemic-cued recall Not all indirect tests display priming effect. Gen Know (indirect, conceptual): V = A Blaxton (1989) Transfer Appropriate Process Conclusions Support view that processing rather than system is what is important

29. Four major approaches have been proposed The Activation view Multiple Memory systems view Transfer appropriate processing view Bias View Accounting for Implicit/Explicit Dissociations

30. The Bias View Proposed to account for repetition priming effects. Prior presentation of an item can bias subsequent processing of the item on later presentations (if you see it once, you are more likely to interpret in the same way later) Multiple systems attributes this to 3 separate systems, but doesn’t really offer an explanation TAP’s answer is considered circular (you respond faster the second time because of transfer appropriate processing, which was developed to account for priming effects)

31. The Bias View Bias View’s account for repetition priming effects. 1. First See one of old woman and young woman 2. Second See ambiguous woman3. People are more likely to interpret the ambiguous picture as the same person as the unambiguous picture 1. First SeeOld WomanYoung Woman 2. Second SeeAmbiguous -> Old Woman Ambiguous -> Young Woman Bias entails both cost and benefits Cost : There will be an advantage if prior processing is appropriate for the current task Benefits : There will be a disadvantage if prior processing is inappropriate for the current task

32. Comparing the theories Strengths Processing perspective No “need” for separate systems (true of Bias view too) Bias View may be seen as a complement to the TAP view Weaknesses Doesn’t explain impact of conscious awareness Trouble with finer grain distinctions between tasks TAPMultiple Systmes Strengths Good fit for deficit data (but may be too easy to propose “new systems”) Weaknesses Has troubles with some data showing differential decline in memory performance with aging Sometimes difficult to make specific predictions in advance

33. Implicit Memory Summary Implicit memory is memory without awareness. Implicit and explicit tasks are not “ process pure ” PDP offers a measurement method for processes Implicit memory is different memory from explicit memory by experimental dissociations. There is 4 main accounts for implicit memory Probably a complex relationship between systems and processes

34. Experiment 2 Recall that for experiment 2 you each collected data from three participants. IV – levels Prediction: our instructions would lead participants to shift their criterion for what counts as old vs. new. Signal detection analysis

35. Signal Detection Theory Recognition accuracy depends on : Whether a signal (noise/target memory) was actually presented The participant’s response Thus, there are four possible outcomes: Hits Correctly reporting the presence of the signal Correct Rejections Correctly reporting the absence of the signal False Alarms Incorrectly reporting presence of the signal when it did not occur Misses Failing to report the presence of the signal when it occurred CORRECT INCORRECT

36. Signal Detection Theory Calculating d’ and C (or β) Discriminability (d’): Step 1) Look up the z-score for the average Hit and False Alarm rates. Step 2) Apply the formula d ’ = z HIT – z FA, where z FA is the z-score for FAs and z HIT is the z-score for Hits. Criteria C (or β) : Take the negative of the average of z HIT and z FA. This is the criterion value C. Remember that positive C values indicate a conservative response bias, while negative C values indicate a liberal response bias. http://memory.psych.mun.ca/models/dprime/

37. Experiment 2 TargetLure “Old”Hit 15.05 0.75 False Alarm 2.48 0.12 Neutral TargetLure “Old”Hit 12.05 0.60 False Alarm 1.14 0.06 TargetLure “Old”Hit 16.95 0.85 False Alarm 4.38 0.22 Conservative Liberal N=21 per condition Total possible hits or false alarms = 20 Averages Proportions (avg/20)

38. Experiment 2 TargetLure “Old”Hit 15.05 0.75 False Alarm 2.48 0.12 Neutral TargetLure “Old”Hit 12.05 0.60 False Alarm 1.14 0.06 TargetLure “Old”Hit 16.95 0.85 False Alarm 4.38 0.22 Conservative Liberal d’ = 1.85 C = 0.25 d’ = 1.81 C = 0.65 d’ = 1.81 C = -0.13 http://memory.psych.mun.ca/models/dprime/

39. Experiment 2 Neutral Conservative Liberal d’ = 1.85 C = 0.25 d’ = 1.81 C = 0.65 d’ = 1.81 C = -0.13 stimulus intensity probability Noise Signal (remember) d’d’

40. Experiment 2 Neutral Conservative Liberal d’ = 1.85 C = 0.25 d’ = 1.81 C = 0.65 d’ = 1.81 C = -0.13 stimulus intensity probability Noise Signal (remember) OldNew - Criterion +

41. Experiment 2 Neutral d’ = 1.85 C = 0.25 stimulus intensity probability Noise Signal (remember) OldNew - Criterion +

42. Experiment 2 Conservative d’ = 1.81 C = 0.65 stimulus intensity probability Noise Signal (remember) OldNew - Criterion +

43. Experiment 2 Liberal d’ = 1.81 C = -0.13 stimulus intensity probability Noise Signal (remember) OldNew - Criterion +