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Operant Conditioning Pavlovian learning how stimuli provide information about other stimuli

Operant Conditioning Pavlovian learning how stimuli provide information about other stimuli Operant learning how your behavior leads to good and bad results Natural selection  effective organisms survive  other ones die out  results in complex well adapted organisms

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Operant Conditioning Pavlovian learning how stimuli provide information about other stimuli

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  1. Operant Conditioning Pavlovian learning how stimuli provide information about other stimuli Operant learning how your behavior leads to good and bad results Natural selection  effective organisms survive  other ones die out  results in complex well adapted organisms Behavioral selection  behavior leading to good outcomes is strengthened  other behavior dies out  results in complex behavior that is suitable for the environment

  2. The Law of Effect (voluntary responses, not reflexes) Responses followed by good things are strengthened Responses followed by bad things are weakened R Re responses (reward or reinforcer) Bad Consequence Good Consequence Behavior produces consequences Positive reinforcement Punishment Behavior eliminates consequences Negative Reinforcement Omission

  3. Increase probability of response The Law of Effect (voluntary responses, not reflexes) Responses followed by good things are strengthened Responses followed by bad things are weakened R Re responses (reward or reinforcer) Bad Consequence Good Consequence Behavior produces consequences Positive reinforcement Punishment Behavior eliminates consequences Negative Reinforcement Omission

  4. The Law of Effect (voluntary responses, not reflexes) Responses followed by good things are strengthened Responses followed by bad things are weakened R Re responses (reward or reinforcer) Bad Consequence Good Consequence Decrease probability of response Behavior produces consequences Positive reinforcement Punishment Behavior eliminates consequences Negative Reinforcement Omission

  5. stop reinforcement spontaneous recovery extinction acquisition rat out of box bar press rate time Operant conditioning may also be subject to inhibition.

  6. no food food positive press bar595contingency Rat learns don’t press0 100 to press! no food food zero press bar595contingency Rat stops don’t press595 pressing or doesn’t learn Contingency vs. Contiguity Does the response have to predict the consequence? Hammond (1980) Supports Contingency

  7. Conditioned Reinforcement Skinner (1938) Phase 1 “click” . . . . . food conditioned primary reinforcer reinforcer Phase 2 Rats learn to press a bar to hear the “click” Other examples praise money grades Conditioned reinforcers only develop when they predict primary reinforcer (more evidence for contingency)

  8. Token Reinforcers • First train animals that tokens can be • exchanged for food • (e.g., vending machine) • Then see if animals will learn other responses • to get tokens • Chimpanzees • tokens work as well as “real” reinforcers • fight over the tokens

  9. Learned Helplessness (Seligman) Phase I - Learning to Escape Shock Control Dogs Yoked Dogs panel • A long lasting shock is given to both groups • every once in a while • Control dogs can turn shock off by pushing a • panel • Yoked dogs’ shock turns off too, when control • dog pushes panel • Yoked dogs can do nothing themselves to escape • shock

  10. Phase 2 - Avoidance Learning hurdle • shock delivered to one side of box • if dog jumps hurdle to other side • there is no shock • Control dogs learn to avoid shock • Yoked dogs don’t • Yoked dogs have learned that they can’t stop shock • They have learned to be helpless

  11. “Curing” learned helplessness • Drag the dog over the hurdle a few times • Eventually learns to avoid shock Curing learned helplessness requires the animal to experience success Depression is like learned helplessness • passive • lose weight • have trouble learning new tasks

  12. Preventing Learned Helplessness If dogs are first exposed to shock that they can turn off and then exposed to uncontrollable shock, they don’t learn to be helpless. Early Experience!

  13. Methods for Studying Memory STUDYTEST retention interval Recall Tests Free recall Serial recall Cued recall

  14. steel thread tights universe cob batteries eye cow pear clarinet nail pitch airplane mittens bunny sprinkler spaghetti saucer canary microphone

  15. Recognition DRUM CORDStudy KITE PARROT yes-noTest CLASS KITE CORD CORNForced Choice KITE BIRD RESPONSE “YES” “NO” OLD ITEM NEW HIT MISS FALSE ALARM CORRECT REJECTION

  16. Experiments with no study phase • Autobiographical Memory • Recall all of your elementary school teachers • Where were you when “Challenger” space • shuttle blew up? • How do you know if recall is accurate? • Semantic Memory • Tests of general knowledge • Easyquestions • “Is an oak a tree?” • measure response time • Hardquestions • Which is bigger, an eagle or a raccoon?

  17. Savings in Relearning Learn Relearn something the same thing How many If it takes trials? few trials, you have memory % savings = trials for trials for original learning relearning trials for original learning Example learning ancient Greek passages STUDY - 1-1/2 year old has Greek passages read to him TEST - Age 8

  18. TEST 10 new passages30 trials 10 old passages 21 trials % savings = = 30% Conclude: There is some memory for old passages 30-21 30

  19. “Classic” or Standard Theory of Memory Selectivity of Encoding Only some information is stored permanently A B C D EF G H I J K L C D E E ] F G H

  20. For closer examination conveyor not good enough Rejects Hi-grade

  21. For closer examination Information from sense organs Sensory Memory conveyor Attention System Short-Term Store not good enough Rejects Forgotten Hi-grade Long Term Store

  22. Classic Theory eyes ears Sensory Memories Iconic Store Echoic Store • large capacity • rapid turnover • “raw” • information Attention Filter • small capacity • symbolic • information Short-Term Store • almost • unlimited • capacity Long-Term Store

  23. Short-Term Store some metaphors 1. Box with Slots (limited capacity) 2. A work bench where thinking takes place parrot pizza jet parrot jet

  24. parrot jet pizza 3. STS is the activated part of long-term store eats fly plane food bird heli- copter ham- burger 4. STS is your consciousness jet parrot pizza

  25. What is in STS? Mental Symbols sound of the word “dog” appearance of the letter “A” world STS LTS perception retrieval from LTS

  26. Sensory Memory forgotten if not rehearsed STS rehearsal keeps item in STS What happens to items in STS? transferred to LTS if rehearsed a lot or if important LTS

  27. What do symbols in STS stand for? (Coding) Classic Theory words & letters are coded by sound (acoustic) OR internal articulation not by meaning Conrad (1964) serial recall of letters confusions are acoustic code must be acoustic

  28. F D K C Y X M B C P C V E T rite right rite wright right write

  29. How is STS Limited? 1. Number Hypothesis STS can hold only a fixed number of symbols 7  2 (Miller) 2. Time Hypothesis Any symbol in STS will be lost in around 2 seconds if it is not reactivated by rehearsal Span of STS is determined by decay rate (2 sec) and the rate of rehearsal

  30. Baddeley, Thomson & Buchanan (1975) tested memory span for words memory span = number of items where immediate serial recall is perfect short words“pig” “bet” long words“noon “rose”(take longer to say to yourself) Memory span was greater for short words Conclude: Your memory span is the number of words you can rehearse in 2 seconds The Time Hypothesis is correct

  31.   Improving STS Capacity 1. Chunking with recoding combine many symbols into one T H E D O G “the dog” 0 0 1 0 1 0 1 1 1 1 2 7 2. Chunking without recoding organize symbols into groups 7 1 6 - 2 7 5 - 7 2 6 1  

  32. Are STS and LTS Really Different? Classic Theory says “yes”! STS a few seconds a few items decay or “getting bumped out” acoustic/ articulatory for words LTS “permanently” “unlimited” retrieval failure anything time capacity cause of forgetting nature of symbols (coding

  33. Immediate Free-Recall Serial Position Curve 100% recall recency primacy asymptote | | | 1 2 3 25 serial position

  34. Immediate Free-Recall Serial Position Curve STS 100% recall LTS nonrecency recency primacy asymptote | | | 1 2 3 25 serial position

  35. Dissociations in free recall serial position curve 1.No dissociation Condition A is easier than B over all positions 2. A is better than B for nonrecency only A is better for LTS 3. A is better than B for recency only A is better for STS Recall A B A B A B

  36. Actual Dissociations Supporting STS-LTS Distinction Independent variable presentation rate SLOW vs. FAST intervening task before recall or no task old-age vs. college-age subjects amnesic vs. normal subjects Effect on Recency SLOW = FAST NO TASK > TASK YOUNG ≈ OLD AMNESIC ≥ NORMAL Effect on Nonrecency SLOW > FAST NO TASK = TASK YOUNG > OLD AMNESIC = 0

  37. Immediate Free-Recall Serial Position Curve 100% recall recency primacy asymptote | | | 1 2 3 25 serial position

  38. Immediate Free-Recall Serial Position Curve 100% recall recency primacy asymptote Negative Recency Effect FINAL FREE RECALL | | | 1 2 3 25 serial position Craik (1970) Recency items are recalled worse than nonrecency items in final free recall Supports STS-LTS distinction

  39. Effects of Marijuana on Memory Darley et al. (1973) start •presentation and immediate free recall of ten lists •administration of drug or placebo after one hour - Phase 1 Final free recall of ten lists Recall .4 - .2- serial position Phase 2 Presentation and immediate free recall of ten new lists Recall .8 - .6 - .4 - .2 - serial position Conclude: Drug hurts transfer from STS to LTS No difference Drug doesn’t effect retrieval from LTS drug placebo Drug is worse on nonrecency only placebo drug

  40. Problems with Classic Theory (1) You can get recency even when STS isn’t involved • Baddeley & Hitch (1977) “Rugby” experiment • Roediger & Crowder (1976) “President” • experiment Ford Washington Lincoln 100% Nixon Recency serial position of presidents

  41. (2) The Classic Theory’s view of rehearsal is wrong Craik & Watkins (1973) Phase 1 keep track of most recent “b” word “basket” “spoon” “telephone” “baby” report “baby” Rehearsal time basket - 2 items Phase 2 recall all “b” words 20— 10 — % recall Actual Data | | | | | | | 0 1 2 3 4 5 6 Rehearsal Time

  42. (2) The Classic Theory’s view of rehearsal is wrong Craik & Watkins (1973) Phase 1 keep track of most recent “b” word “basket” “spoon” “telephone” “baby” report “baby” Rehearsal time basket - 2 items Phase 2 recall all “b” words (sheer amount of rehearsal doesn’t matter always) If classic theory is right 20— 10 — % recall Actual Data | | | | | | | 0 1 2 3 4 5 6 Rehearsal Time

  43. Levels of Processing Theory of Memory A modification of the Classic Theory • Craik & Lockhart (1972) • memory is determined by encoding • the “deeper” the processing during encoding, the • better the memory • amount of rehearsal is not important • distinction between STS (primary memory) and • LTS (secondary memory) is still present

  44. Craik & Lockhart (1972) Kinds of rehearsal maintenance - keep repeating word at shallow (phonemic) level KEEPS WORD AVAILABLE, but DOES NOT improve long-term memory for word elaborative - think about the meaning of the word in lots of different ways (semantic) does improve long-term memory

  45. Relation Between Rehearsal and Perception What happens when you perceive a word? D O G Stage 1detect parts of letters (visual) recognize letters “D” “O” “G” Stage 2convert letters to “phonemes” (phonemic) D = d O = o G = hard g Stage 3convert phonemes to meaning (semantic) “d o g” = pet that barks

  46. Event: D O G concentrate on letters poor memory concentrate on sound fairly short memory concentrate on meaning long lasting memory shallow letters (visual) sound (phonemic) meaning (semantic) deep

  47. 1. Personally significant? 2. 2 syllables? 3. Animate? 4. Personally significant? 5. 2 syllables? 6. Animate? 7. Personally significant? 8. 2 syllables? 9. Animate? 10. Personally significant? 11. 2 syllables? 12. Animate? 13. Personally significant? 14. 2 syllables? 15. Animate? 16. Personally significant? 17. 2 syllables? 18. Animate? 19. Personally significant? 20. 2 syllables? 21. Animate?

  48. Watkins & Watkins, 1974 list length known list length unknown immediate recall final recall serial position Supports the idea that negative recency in final recall is due to shallow processing when list length is known (maintenance rehearsal)

  49. Support for Levels of Processing Craik & Tulving (1975) Orienting questions Caseword in capital letters TABLE subject respondsyes Rhymeword rhymes with weight? MARKET subject respondsno Sentenceword fits in sentence “He met a _______” FRIEND subject respondsyes

  50. yes .8 .6 .4 .2 sentencerhymecase no yes Probability of “Hit” in Recognition no yes no Deeper means better memory “yes” better than “no” (elaboration)

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