Amnesia from Brain Damage

1. Amnesia from Brain Damage Concussion Shock Lesions Drugs Alcohol (Korsakoff’s syndrome) Back

2. Symptoms Retrograde Amnesia (RA) Anterograde Amnesia (AA) You usually have both Retrograde Loss of memory for events prior to the damage Loss is greatest for time right before damage Is RA a retrieval or storage deficit? You can recover from RA Therefore, it is a retrieval deficit

3. RA in rats (Winocur’s experiment) (only forget things for a few days before damage) Phase 1 rats learn to associate a reward with a particular smell Phase 2 Control Group No lesion to hippocampus Experimental Group Hippocampus is lesioned either 1,7, or 14 days after learning control memory for phase 1 experimental | | | 14 7 1 days since learning

4. RA in people (Butlers & Cermak (1986)) Patient P.Z. University professor who developed amnesia in 1982 (had written autobiography three years before) Recall of facts from book 90 – 50 – RA  % Correct      | | | | | | before 1930 1940 1950 1960 1970 1980

5. Immediate Free Recall normals amnesics Anterograde Amnesia Loss of memory for events after damage Does AA affect STS or LTS? Baddeley & Warrington serial position Maintenance in STS is not affected Problem is with LTS

6. Is AA due to failure to transfer to LTS or failure to retrieve from LTS? If you can recover from AA, you still can never retrieve the events that happened while you had AA Therefore, AA is a failure to transfer to LTS

7. Not all LTS is affected in amnesia • Lost • performance in explicit memory tasks • (recall, recognition) • learning new vocabulary • learning new facts (semantic memory) • Not Lost • implicit memory (e.g., stem completion) • ability to learn new skills • Milner (1965) Trace star using mirror mirror Amnesics learned as fast as normals

8. Cohen’s Tower of Hanoi Experiment Normals and amnesics must learn how to solve problem Result Normals and amnesics learn task at the same speed Amnesics don’t remember having done the task Amnesics have normal ability to learn new skills

9. A Theory of Amnesia Procedural/Declarative Theory (Cohen) Amnesia is a disorder of declarative memory (episodic and semantic memory) Procedural memory is normal skill learning o.k. implicit meaning o.k.

10. What does the hippocampus do? It allows us to combine different kinds of knowledge to make new memories. If the hippocampus is gone, what happens? Can’t form new memories for events (can’t combine parts of events) Can’t store new propositions (can’t learn new facts) (can’t remember what you read)

11. Why do you lose recent old memories (RA) as well as the ability to form new memories (AA)? It takes time (weeks, months) to completely lay down a new memory. You need the hippocampus to hold onto recent memories before they are completely formed.

12. What can you do without a hippocampus? Your STS is o.k. (activation of existing parts of network) You can strengthen existing connections in LTS (explains some kinds of implicit memory) (and why procedural memory is o.k.)

13. Hypnosis & Memory • 1. Can difficult-to-retrieve memories be • reached through hypnosis? • 2. What is the nature of post-hypnotic amnesia. • Post-hypnotic Amnesia • loss of memory for events during hypnosis • caused by suggestion from hypnotist • Why is it important? •  causes of forgetting •  semantic/episodic memory

14. Evans & Kihlstrom subjects hypnotized and given 12 tests heading nodding eyes close hand lowering arm immobilization finger lock arm rigidity hands moving together communication inhibition fly hallucination eye catalepsy post hypnotic suggestion to touch ankle post hypnotic amnesia suggestion subject is awakened

15. Perfect Amnesia 20 - 15 - 10 - 5 -  Distribution of number of items recalled    % of subjects          | | | | | | | | | | | | | 0 1 2 3 4 5 6 7 8 9 10 11 12 Subjects with perfect amnesia either think hypnosis was brief or recognize that there’s a gap in their memory.

16. “Try to recall as many tests as you can” 9 – 8 – 7 – 6 – 5 – 4 – 3 – 2 – 1 – Hi Medium Lo Hypnotizability of Subjects Hi subjects had vague recall “something about a fly” Lo subjects had specific recall “You tried to get me to think there was a fly”

17. “Try to recall as many tests as you can” “Now you can remember everything” 9 – 8 – 7 – 6 – 5 – 4 – 3 – 2 – 1 – Recall is equal after amnesia is lifted Retrieval Failure Hi Medium Lo Hypnotizability of Subjects Hi subjects had vague recall “something about a fly” Lo subjects had specific recall “You tried to get me to think there was a fly”

18. Are the memories completely blocked before amnesia suggestion is lifted? Hull (1933) Subjects experiencing post-hypnotic amnesia show savings in re-learning TOLD TO FORGET Group 1 Learn Relearn List A list A Group 2 Rest Learn list A TOLD TO FORGET Group 1 does much better

19. Graham & Patton (1968) Blocked items still cause RI 1. Learn list A Learn B Test A 54% 2. Learn list A Rest Test A 87% 3. Learn list A Learn B Test A 46% TOLD TO FORGET Groups 1 and 2 Hypnotized Group 1 shows as much RI as Group 3

20. Williamson, Johnson & Erikson (1965) Subject hypnotized (high hypnotizable) Learned list many, pencil, work . . . Awakened Test recall (could recall almost none) Fragment completion m _ n _ OLD p e_ _ i _ OLD t _ n _ NEW Solved fragments much more often for old words . . .

21. Search for Memories Decide if they are the ones you want Recall Recognition Decide if items are the ones you want Relation between Recall and Recognition Phase 1 Phase 2 Hypnotic amnesia occurs in recall, but not really in recognition. Therefore, it affects the search phase of retrieval

22. Hypnotic Enhancement Alien abduction?? Recall of former lives?? Police work L.A.P.D. Study 70 volunteer witnesses hypnotized 77% of cases got “useful” information from hypnosis BUT NO CONTROL GROUP People vs. Shipley (1982) Supreme court decision Hypnosis does not contribute to accurate testimony

23. Hypnosis leads to more false recall Shaul (1978) hypnotized subjects showed more correct recall, but also more false recall Hypnosis leads to unjustified confidence Putnam (1979) stop-sign yield-sign experiment hypnotized subjects were not more accurate at choosing the correct sign. But they were more confident

24. Details of an Example Study Rudman (1984) Does hypnosis aid recognition memory? PHASE 1 (1) Subject enters room (2) Confederate enters room, apologizes and leaves (3) Subject hypnotized and tested for susceptibility (4) Subject “awakened” and told they may be asked back PHASE 2 24 highly hypnotizable subjects called back 1 month later to the same room 3 groups 8 8 8 Hypnotized Simulators Not hypnotized

25. Subjects told to “visualize” the last time in room. Five photographs of people forced choice recognition and rate confidence Results Number correct (out of 8) Hypnotized 6 Simulators 5 Not Hypnotized 6 No difference in recognition Number who were confident (out of 8) Hypnotized 8 Simulators 4 Not Hypnotized 1 Hypnotized subjects were more confident

26. Criterion Shift Hypothesis Hypnosis does not change the accuracy of memory search processes. But it does make the subject more willing to call something a memory.  False Recall  False Alarms in Recognition  Higher Confidence

27. How criterion shift might work Study List:DOG TREE CUP . . . ON LIST weaker link DOG TREE CUP chase has over CAT LEAVES SAUCER

28. How criterion shift might work Study List:DOG TREE CUP . . . ON LIST weaker link DOG TREE CUP DOG TREE DOG CUP chase has over CAT LEAVES CAT LEAVES SAUCER Memory search works by spreading activation Recall everything more activated than some criterion, e.g., 10 units of activation

29. How criterion shift might work Study List:DOG TREE CUP . . . ON LIST weaker link RECALL “dog” “tree” DOG TREE CUP DOG TREE DOG CUP chase has over CAT LEAVES CAT LEAVES SAUCER Memory search works by spreading activation Recall everything more activated than some criterion, e.g., 10 units of activation

30. How criterion shift might work Study List:DOG TREE CUP . . . Hypnotized Shift criterion down to 5 ON LIST weaker link RECALL “dog” “tree” “cup” “cat” “leaves” DOG TREE CUP DOG TREE DOG CUP chase has over CAT LEAVES CAT LEAVES SAUCER More words are recalled because more words are activated above the lower criterion. “cat” and “leaves” are falsely recalled

31. Does music aid performance on cognitive tasks? The Mozart Effect Rauscher, Shaw & Ky (1993) Listen to 10 minutes of Mozart Listen to 10 minutes of repetitive music 10 minutes of Silence Test on spatial abilities e.g., jig-saw puzzles mental rotation Result: You’re better after the Mozart Interpretation Brain regions for musical processing are shared with regions for spatial processing. (Music “warms up” these regions.)

32. Is the Mozart Effect For Real? Nantais and Schellenberg (1999) Exp 1 Exp 2 score on test Mozart 12.8 Mozart 13.0 Silence 11.9 Interesting Story 12.9 significant difference no difference Subjects who preferred Mozart Subjects who preferred story Mozart 14.6 11.6 Story 13.2 12.7 • Conclude: There’s nothing special about Mozart or any • music for enhancing spatial tasks. • Doing anything interesting right before the test helps • performance, compared to being bored.

33. Repression “The essence of repression lies in simply rejecting and keeping something out of consciousness.” —Freud Does this happen? Of course. Everyday Repression (1) turn away from unpleasant things poor encoding Peters (1988) poorer recognition of nurse who gives inoculation than for a neutral helper

34. (2) Don’t think about unpleasant things • fewer rehearsals, poor memory • Meltzer (1950) • Students forgot more of the • unpleasant memories that occurred • over the holidays • Real “Freudian” Repression • painful information is kept out of consciousness • without the person being aware that they are • rejecting it • can lead to mental illness

35. Two Kinds of Repression Perceptual Defense Sensory Memory STS Memory Defense STS LTS

36. Perceptual Defense TABOO WORD 15 msec Taboo words must be flashed for a longer duration before subjects report the word. Conclusion Indeterminant Subjects may be less likely to report seeing a taboo word.

37. Is a Taboo Word Effect Perceptual? (Zajonc (1962) Group 1 Group 2 seesayseesay TABOO dog whore TABOO whore dog CONTROL cat where CONTROL where cat TABOO needs no difference longer exposure Effect is due to the reluctance to say TABOO words

38. Memory Defense Psychogenic Amnesia Loss of memory from “psychological” causes. Loss for specific situation, or temporary loss of identity Specific Situation Case of Madame D. (Janet). Told of husband’s death (as a joke). Became unable to remember event. (gradually memory returned) Loss of Identity (who you are) Fugue State Sometimes you “flee” current circumstances

39. Only detailed study of psychogenic amnesia • P.N. studied by Schacter, Wang, Tulving & • Freeman (1982) • Episode occurs after grandfather’s funeral • lasted 4 days • lost most episodic memories • retained semantic memories • loss was retrograde more than anterograde • Organic • more A.A. • lose episodic & • semantic • brain damage • Psychogenic • more R.A. • lose episodic & • personal identity • traumatic events

40. Dissociative Identity Disorder (Multiple Personalities) Personalities may not remember events experienced by other personalities (interpersonality amnesia) Eich, Macaulay, Lowenstein & Dihle (1997)’s experiment Phase 1 “Frank” is replaced by “Jim” “Jim” reads 20 words “Jim” does test of picture fragment completion What is this?

41. Phase 2 “Jim” is replaced by “Henry” (“Henry” is told “Jim” heard words. “Henry could not recall ANY of them - NO FREE RECALL) “Henry” does cued recall for words that “Jim” saw. Cue is first three letters. “Henry” gets 20 new words “Henry” does picture fragment completion 5 pictures were done by “Jim” 5 pictures were new

42. Picture Fragment Completion –2.0 –1.0 improvement from seeing picture before Jim Jim Jim Henry Henry Jim There is implicit memory (picture fragment completion) across different personalities

43. Phase 3 • “Jim” comes back • “Jim” could not free recall any of “Henry’s” • words • cued recall for “Henry’s” words • cued recall for his own words • (from Phase 1) • picture fragment completion • 5 new pictures • 5 “Jim” had seen • 5 “Henry” had seen

44. Results Cued Recall 50 – 40 – 30 – 20 – 10 – study test “Jim” “Jim” “Jim” “Henry” “Henry” “Jim” Very poor explicit memory across different personalities

45. Self- Concept 1 Why is interpersonality amnesia found in recall only? Explicit, episodic memory Self- Concept 2 episodic memories Semantic Memory Procedural Memory (perceptual skills) picture identification