PSY 368 Human Memory

1. PSY 368 Human Memory Neuropsychology & Memory Review for Exam 2

2. Announcements • Focus Questions for Weldon and Roediger (1987) Due Monday Today • Exam 2 Wednesday (March 28)

3. Alzheimer’s Disease • Alzheimer’s disease • Cortical, progressive dementia • Criteria • deficit in two or more areas of cognition, at least one of which is memory • interferes with social or occupational functioning • decline from premorbid level • gradually progressive course • rule out other causes

4. Alzheimer’s Disease • Alzheimer’s disease (video clip # 19, ~7mins) • Cortical, progressive dementia • Disease is associated with the development of neuro-fibrillary tangles and plaques • To stay healthy, neurons must communicate with each other, carry out metabolism, and repair themselves. • AD disrupts all three of these essential jobs. Pet Scan of Normal Brain Pet Scan of Alzheimer’s Disease Brain

5. Alzheimer’s Disease • Signs of AD are first noticed in the entorhinal cortex, then proceed to the hippocampus. • Affected regions begin to shrink as nerve cells die. • Changes can begin 10-20 years before symptoms appear. • Memory loss is the first sign of AD. • Alzheimer’s disease Preclinical AD

6. Alzheimer’s Disease • AD spreads through the brain. The cerebral cortex begins to shrink as more and more neurons stop working and die. • Mild AD signs can include memory loss, confusion, trouble handling money, poor judgment, mood changes, and increased anxiety. • Moderate AD signs can include increased memory loss and confusion, problems recognizing people, difficulty with language and thoughts, restlessness, agitation, wandering, and repetitive statements. • Alzheimer’s disease Mild to Moderate AD

7. Alzheimer’s Disease • In severe AD, extreme shrinkage occurs in the brain. Patients are completely dependent on others for care. • Symptoms can include weight loss, seizures, skin infections, groaning, moaning, or grunting, increased sleeping, loss of bladder and bowel control. • Death usually occurs from aspiration pneumonia or other infections. Caregivers can turn to a hospice for help and palliative care. • Alzheimer’s disease Severe ADs

8. Alzheimer’s Disease • Alzheimer’s disease • The brains of people with AD have an abundance of two abnormal structures: • Beta-amyloid plaques • Dense deposits of protein and cellular material that accumulate outside and around nerve cells • Neurofibrillary tangles • Twisted fibers that build up inside the nerve cell An actual AD plaque An actual AD tangle

9. Alzheimer’s Disease • Alzheimer’s disease • Relatively intact articulatory loop of WM • three types of memory problems • WM – verbal and spatial memory impairments • Episodic memory impaired (e.g., free recall) • Executive function • Semantic memory is also impaired • Naming and word generation impaired in AD • Note: pure amnesics do not have the latter two impairments

10. Exam 2 Review • Chapter 5: Memory Processing • Chapter 6: Forgetting • Chapter 7: Implicit Memory • Chapter 8: Neuropsychology and Memory • Chapter 9: Recognition

11. Exam 2 Review • Chapter 5: Memory Processing • Craik & Lockhart (1972), Levels of processing (slide 16) • Craik & Tulving (1975) – good experimental evidence supporting LOP (deeper processing remembered better) (slide 17) • Transfer Appropriate Processing • Morris, Bransford, & Franks (1977) – good experimental evidence supporting TAP (match of processing at encoding and retrieval more important than LOP) (slide 18-21) • Context effects (similar context at encoding & test, better memory) • Encoding Specificity Principle (Thompson & Tulving, 1970)(slide 22-23)

12. Exam 2 Review • Chapter 6: Forgetting • Ebbinghaus and forgetting function (slide 24) • Permastore (see Bahrick studies) (slides 25-27) • Retrospective vs. Prospective memory • Theories of forgetting • Failure of Consolidation • Decay • Context/cue mismatch • Interference (retroactive and proactive) (slides 28-29)

13. Exam 2 Review • Chapter 7: Implicit Memory • Implicit memory tasks (vs. explicit tasks) (slides 30-31) • Process Dissociation Procedure (Jacoby, 1991) (slides 32-34) • Theoretical accounts • The activation view • Multiple memory systems (slide 35) • Transfer appropriate processing • Blaxton (1989) (data vs. conceptual driven, or direct vs. indirect) (slides 36-40) • Bias view

14. Exam 2 Review • Chapter 8: Neuropsychology and Memory • Methods of study (slide 41) • Neurons and the Brain (slides 42-45) • Hippocampus • Memory Disorders • Amnesia (slide 46) • Anterograde • retrograde • Alzheimer’s Disease (today’s lecture, slides 3-9)

15. Exam 2 Review • Chapter 9: Recognition • Recall vs. Recognition • Signal Detection Method (slide 47) • Single vs. dual process theories (slides 48-51) • Tagging Model • Strength Theory • Generate-Recognize Model • Remember/Know Processes Model • Face Recognition (slide 52)

16. Level of Processing • Considered level of processing at study to be more important for memory than intent to learn • Levels of processing = how “deeply” the item is processed • The depth of processing helps determine the durability in LTM. Craik & Lockhart (1972) SHALLOW DEEP

17. Levels of Processing Craik and Tulving (1975) Task: • Participants viewed words and were asked to make three different types of judgments: • Visual processing (e.g. “Is LOG in upper case?” Y/N) • Phonological (e.g. “Does DOG rhyme with LOG?” Y/N) • Semantic (e.g. “Does DOG fit in the sentence: ‘The ___ chased the cat’?” Y/N) • Finally, participants were asked to recognize the words they had seen before in a surprise test including both old and new words.

18. Transfer-appropriate processing Morris, Bransford, and Franks (1977) • Task: • Participants made either a phonological or semantic judgment about each item on a word list. • Study: eagle (yes/no fits clue) • Deep - The ____ is the US national bird. • Shallow - rhymes with legal • The learning was incidental: participants were not told that they would have to later recall the words. • This constrains (limits) the learning strategies used.

19. Transfer-appropriate processing Morris, Bransford, and Franks (1977) • Task: • The final test was either: • A standard recognition test for the learned words. • A rhyming recognition test for learned words • e.g., Was a word presented that rhymed with “regal”?.

20. Transfer-appropriate processing Morris, Bransford, and Franks (1977) • Results: • Standard recognition test: Deeper processing led to better performance. • Rhyming recognition test: The shallower rhyme-based encoding task led to better performance because it matched the demands of the testing situation.

21. Transfer-appropriate processing Morris, Bransford, and Franks (1977) • Conclusion: • The take-home message is that when the processing at encoding matches the processing at retrieval, performance will be better. • It only makes sense to talk about a learning method’s efficiency in the context of the type of final test.

22. Encoding Specificity Principle Thompson and Tulving (1970) • Examined effectiveness of cue • Had people learn lists of strong or weak associates. • Strong vs. weak cues (“flower”) • Strong: bloom • Weak: fruit • Study: no cue vs. weak cue • Test: no cue, weak cue, or strong cue

23. Encoding Specificity Principle Thompson and Tulving (1970) • Thompson and Tulving showed that this can be reversed if you change the study context. • The best retrieval cue for a word like “flower” would be a strong associate like “bloom.”“fruit” is weakly associated to “flower,” and would be unlikely to pull it out.

24. Forgetting Ebbinghaus (1885) Rapid forgetting for short delays - slower for longer delays Memory Performance

25. What do we forget? • Permastore: • Describes the leveling off of the forgetting curve at long delays. • Beyond this point, memories appear impervious to further forgetting. Bahrick (1984) • Permastore • Rapid forgetting of foreign language for 3 yrs, • Then of a asymptotes (levels off) after about 2 years, • Stays fairly constant even up to 50 yrs. • The overall level of retention is determined by the level of initial learning. PERMASTORE

26. Permastore Bahrick, Bahrick & Wittlinger (1975) • Tested nearly 400 high-school graduates on their ability to recognize and name classmates after delays of up to 30 years. • Questions • Recall • Can you list all your classmates? • Can you name all these faces? • Recognition • Is this the name of a classmate? • Is this the face of a classmate? • Match these names and faces

27. Permastore Bahrick, Bahrick & Wittlinger (1975) • Tested nearly 400 high-school graduates on their ability to recognize and name classmates after delays of up to 30 years. Recognition Name Matching Results were mixed: • Relatively unimpaired: • Ability to recognize their classmates’ faces/names. • Ability to match up names to the appropriate portraits. Recall Name the picture • Extensively impaired: • Ability to recall a name, given a person’s portrait. 3.3 mons. 47+ yrs. Conclusion: • Recall, but not recognition,of well-learned personal material, closely follows the forgetting curve first demonstrated by Ebbinghaus (1913).

28. How do we forget? • Forgetting caused by encoding new traces into memory in between the initial encoding of the target and when it is tested. • Introducing a related second list of items impairs recall of the first list compared to a control condition. • Retroactive Interference (RI)

29. How do we forget? • The tendency for older memories to interfere with the retrieval of more recent experiences and knowledge. • The number of previous learning experiences (e.g. lists) largely determines the rate of forgetting at long delays. • Proactive Interference (PI)

30. Memory Tasks Test Instructions • Also “Non-declarative” & “procedural” (Squire, Knowlton, & Mesen, 1993) Study Instructions Implicit Memory: Often defined as "memory without awareness”

31. Implicit Memory Tasks Often defined as "memory without awareness” Perceptual Tasks Word identification Word stem completion Word fragment completion Degraded word naming Anagram solution Lexical decision Non-Verbal Tasks Picture fragment naming Object decision task Possible/impossible object decision Conceptual Tasks Word association Category instance generation Answering general knowledge questions

32. Mixing Measures • Tasks are not “process pure” (Jacoby, 1991) • Indirect measures of memory may be “contaminated” by intentional uses of memory • E.g., in stem completion task, subjects might remember items from previous list and use them to complete the stems • Direct measures may be influenced by unconscious or automatic influences (Jacoby, Toth, & Yonelinas, 1993) • Process-Dissociation Procedure was developed to separate automatic (unconscious) and conscious processes

33. Process Dissociation Procedure Jacoby (1991) • Read a list of words – List 1 • Hear a list of words – List 2 • Two recognition tests: • Both tests include List 1, List 2 and novel words. • Inclusion = complete task with studied or any item • Respond “old” if word was on either list. • Exclusion = complete task with item NOT studied (exclude studied items) • Respond “old”only if word was on List 2.

34. Process Dissociation Procedure Jacoby (1991) • Can calculate C and A for each condition in the experiment • C = (Proportion of studied items in inclusion) - (Proportion of studied items in exclusion) • A = (Proportion of studied items in exclusion) / (1-C) • The C and A values are estimated as proportions - values between 0 and 1.0 • Data • Proportion of studied items in inclusion = C + (1-C)(A) • Proportion of studied items in exclusion = (1-C)(A)

35. Multiple Memory Systems • What is a system? • Schacter and Tulving (1994) 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

36. Transfer Appropriate Process Blaxton (1989) • Goal to demonstrate • data-driven processing can affect direct tests • data-driven processing do not necessarily affect indirect tests

37. Transfer Appropriate Process Blaxton (1989) S’s saw or heard lists of words (key IV here) Target word: bashful • graphic-cued recall: looks like “bushful” • free recall • frag completion: b_sh_u_ • General knowledge: “Name one of the 7 dwarfs”

38. Transfer Appropriate Process Blaxton (1989) 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 Same pattern of results regardless of modality Visual better than auditory for both

39. Transfer Appropriate Process Blaxton (1989) 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 Visual should be better than auditory Visual and auditory should be about the same

40. Transfer Appropriate Process Blaxton (1989) 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 • Conclusions • Support view that processing rather than system is what is important

41. Methods of Study • Neuroscientists typically study memory in animals • Can record electrical or chemical signals directly from individual neurons, or carefully remove small portions of the brain • Psychologists typically study memory in humans • More limited techniques • “Experiments of nature” Case studies • Lesions • Direct electrical stimulation • Neuroimaging techniques

42. The Neuron • Dendrites • Cell body • Axon • Myelin sheath • Terminal buttons • Synapse • Billions of synapses nice reference web page

43. Neurons and Memory • Hebbian Learning: • Cells that fire together wire together • Connections between neurons are weighted • Weights can be changed based on feedback from later cells • Basic assumption of most computational neural network models (connectionism)

44. Structure of the brain Other Crucial Parts • Limbic system: controls emotions and instinctive behavior (includes the hippocampus and parts of the cortex) • Thalamus: receives sensory and limbic information and sends to cerebral cortex • Hypothalamus: monitors certain activities and controls body’s internal clock • Hippocampus: where short-term memories are converted to long-term memories

45. Hippocampus • Important for formation of new episodic memories • Important for encoding perceptual aspects of memories • Novel events, places, and stimuli • Important for declarative memory • Especially as part of medial temporal lobe • Supported by case of HM • Video (location, 1 min) • Video (damage, 7 mins)

46. Amnesia • Loss of memory ability - usually due to lesion or surgical removal of various parts of the brain • Relatively spared performance in other domains • A pure amnesia is relatively rare • Two broad categories: • Retrograde: loss of memories for events prior to damage • Anterograde: loss of ability to store new memories of events after damage

47. 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

48. How does Recognition work? • Two classes of theories • Single process theories - retrieval is one process regardless of task • Dual process theories - two processes needed for retrieval - can be task dependent

49. Dual-process theories Generate-recognize model (G-R) • Recall is made up of two processes • First, generate a set of plausible candidates for recall (Generationstage) • Second, confirm whether each word is worthy of being recalled (Recognitionstage – not the same as the recognition test) • Recognition is made up of only one process • Because the experimenter provides a candidate, recognition does not need the generation stage

50. Dual-process theories • Remember versus Know Process Model (Tulving , 1985; Gardiner, 1988) • Relatively recent change in recognition methodology • Does someone • Specifically remember • Conscious recollection of the information’s occurrence at study • Just somehow know • Knowing that it was on the list, but not having the conscious recollection, just a “feeling of knowing”