1. Memory and the Brain Watch “The Locus of Learning and Memory” (6:28) Module #16 from The Brain: Teaching Modules (2 nd edition). http://www.learner.org/vod/vod_window.html?pid=1584 Watch first 3 minutes on Lashley’s experiment. What were his findings regarding the location of memory? View Penfield’s experiment. What were his findings & why are they flawed?

2. Biological Basis of Memory Believed that memory was localized – specific memory stored in a specific area. Removed parts of rat’s cerebral cortex but found no one area contained the memory of the maze Found that maze-learning in rats was distributed throughout the brain Karl Lashley searched for a localized memory trace or engram

3. Biological Basis of Memory Thought that cerebellum was changed after classically conditioning a rabbit to blink to a tone. He was right! Removing this area caused the rabbit to no longer blink to a tone but only reflexively. Shows localized memory. This did not work for complex behaviors like running a maze, which seem to be distributed Richard Thompson Reflexive behaviors are localized in the cerebellum

4. Biological Basis of Memory fMRI shows that when people memorized the label “dog” with the sound of a bark the auditory cortex activated when they retrieved it. Those memorized the label “dog” to a picture activated their visual cortex when they retrieved it. Retrieving a memory reactivates the sensory area of the cortex that was involved in the initial perception of the event.

5. New Memories in a Snail Aplysia—a sea snail was used to study how memories can change neurons Eric Kandel

6. Kandel’s Sea Snail Experiment & LONG TERM POTENTIATION Squirted it with water followed by an electric shock that classically conditioned it to withdrawal its gills next time it was squirted. This changed the three neuron circuit in the snail. Function of the neuron changed with increase in the amount of the neurotransmitter produced by the neuron. Structure of the neuron changed with the number of interconnecting dendrites and axon terminals increasing allowing for more communication points (synapses). http://www.pbs.org/wgbh/nova/body/aplysia-memory.html

7. Severe Memory Loss Amnesia—severe memory loss 3 Major Types: 1.Retrograde Amnesia 2.Anterograde Amnesia 3.Infantile Amnesia

8. Retrograde amnesia Inability to remember past episodic information; common after head injury; Usually regain most; from earliest to more recent Often to not fully regain most recent – Why? – M ay disrupt memory consolidation – gradual, physical process of converting a long-term memory to a stable and enduring memory code. – If disturbed before the process is complete, memory could be lost. – Sleep seems to be when most memory consolidation occurs

9. Anterograde amnesia Inability to form new memories; related to hippocampus damage – Hippocampus key to encoding of new memories and transferring them from STM to LTM. – Implicit memories like procedural memories still occur (hippocampus uninvolved in implicit) – Explicit memory is affected (hippocampus involved in explicit).

10. Infantile Amnesia Inability to recall events from the first few years of life. Possible Reasons for this: 1.Too many differences between the world of an infant and ours for us to be able to make connections or retrieval cues to retrieve them (encoding specificity principle). 2.Hippocampus is still developing so they cannot form new LTM but they can make procedural memories. 3.One reason adults typically recall little of their first three years of life is that during infancy they were unable to verbally label most of their experiences (semantically encode the info).

11. Brain Structures Involved in Memory

12. Watch “How Memory Works” from Nova http://www.pbs.org/wgbh/nova/body/how-memory-works.html What we learned from H.M.

13. Memory in Action Nova An actual long term memory forming: http://www.pbs.org/wgbh/nova/body/memory-action.html

14. FORGETTING & MEMORY CONSTRUCTION

15. Why do we forget? Forgetting can occur at any memory stage Retrieval from long-term memory Depending on interference, retrieval cues, moods, and motives, some things get retrieved, some don’t Long-term storage Some items are altered or lost Short-term memory A few items are both noticed and encoded Sensory memory The senses momentarily register amazing detail

16. Forgetting as Encoding Failure

17. Encoding Failures People fail to encode information because: – It is unimportant to them – It is not necessary to know the information – A decrease in the brain’s ability to encode (age)

18. Forgetting as encoding failure Info never encoded into LTM Encoding X Long-term memory Encoding failure leads to forgetting Short-term memory

19. Encoding Failure What is the color of the top stripe of the American flag? The bottom stripe? How many red and how many white stripes does it have? In what hand does the Statue of Liberty hold her torch? Most wooden pencils are not round. How many sides do they typically have? The White House is pictured on the back of a $20 bill. What is on the back of a $10 bill? A $5 bill? A $1 bill?

20. Forgetting as Storage Failure

21. Hermann Ebbinghaus (1850-1909) German philosopher who did early memory studies with nonsense syllables Developed the retention curve as well as the forgetting curve, also called “Ebbinghaus curve”

22. Ebbinghaus’ Retention Curve Ebbinghaus found that the more times he practiced a list of nonsense syllables on day 1, the fewer repetitions he required to relearn it on day 2. Said simply, the more time we spend learning new information, the more we retain.

23. Ebbinghaus’ Forgetting Curve Most forgetting happens within the 1 st 9 hours after it is learned. Decline levels off; you do not completely forget.

24. How to combat the Forgetting Curve: Overlearning Continuing to rehearse after the point the information has been learned/past the point of mastery Helps ensure information will be available even under stress

25. Forgetting as Retrieval Failure: Interference

26. Forgetting as retrieval failure Retrieval—process of accessing stored information Sometimes info IS encoded into LTM, but we can’t retrieve it Retrieval failure leads to forgetting Retrieval X Encoding Short-term memory Long-term memory

27. Interference Theories “Memories interfering with memories” Forgetting NOT caused by mere passage of time Caused by one memory competing with or replacing another memory

28. Two Types of Interference Types of Interference Retroactive Interference Proactive Interference

29. Retroactive Interference When a NEW memory interferes with remembering OLD information Example: When new phone number interferes with ability to remember old phone number

30. French 101 Mid-term exam Retroactive Interference Example: Learning a new language interferes with ability to remember old language F- Study French papier livreplume école Study Spanish papel libropluma escuela retroactive interference

31. Proactive Interference Opposite of retroactive interference When an OLD memory interferes with remembering NEW information Example: Memories of where you parked your car on campus the past week interferes with ability find car today

32. Proactive Interference Example: Previously learned language interferes with ability to remember newly learned language F-

33. Review of Interference Theory Retroactive Interference – First Learn A, Then Learn B Recall A, B interferes Proactive Interference – First Learn A, Then Learn B Recall B, A interferes Retro & Pro refer to what you want to remember. Interference reflects competition between responses.

34. Motivated Forgetting Undesired memory is held back from awareness – Suppression—conscious forgetting (has empirical support) – Repression—unconscious forgetting (Freudian; lacking empirical support)

35. Repression Part of Freud’s psychoanalysis – We move anxiety-producing memories to the unconscious – Protects us from painful memories Not well-supported by research; stressful incidents are actually more likely to be encoded (Loftus)

36. Decay Theories Memories fade away or decay gradually if unused Time plays critical role Ability to retrieve info declines with time after original encoding Average percentage of information retained 20 mins 1 hr 8 hrs 24 hrs 2 days 6 days 31 days Interval between original learning of nonsense syllables and memory test 100%

37. Decay Theory When new memory formed, it creates a memory trace –a change in brain structure or chemistry If unused, normal brain metabolic processes erode memory trace Theory not widely favored today Evidence AGAINST: Ability of people to retrieve memories from long ago with retrieval cues

38. Memory Construction Elizabeth Loftus

39. Memory Jigsaw Analogy Memories, rather than being like a video tape, are formed as bits and pieces. People may retrieve only some of the pieces of the memory http://www.cbsnews.com/video/watch/?id=4852622n&tag =mncol;lst;2 60 Minutes Manufacturing Memories http://www.cbsnews.com/video/watch/?id=4852622n&tag =mncol;lst;2

40. Elizabeth Loftus (1944- ) Does research in memory construction Has found that subjects’ memories vary based on the wording of questions Demonstrated the misinformation effect – Incorporating misleading information into one’s memory of an event – Affects eyewitness testimony – http://www.cbsnews.com/video/watch/?id=4852620n&tag= mncol;lst;1 60 Minutes – The Bunny Effect http://www.cbsnews.com/video/watch/?id=4852620n&tag= mncol;lst;1

41. Memory Distortion Memory can be distorted as people try to fit new info into existing schemas Giving misleading information after an event causes subjects to unknowingly distort their memories to incorporate the new misleading information http://vsx.onstreammedia.com/vsx/pbssaf/search/PBSPlayer?assetId=68521&ccstar t=1980678&pt=0&vid=pbssaf1402&entire=No (Scientific American Frontiers – Don’t Forget episode; “When Memory Lies” segment; 7:15) http://vsx.onstreammedia.com/vsx/pbssaf/search/PBSPlayer?assetId=68521&ccstar t=1980678&pt=0&vid=pbssaf1402&entire=No

42. Loftus Experiment Subjects shown video of an accident between two cars Some subjects asked: How fast were the cars going when they smashed into each other? Others asked: How fast were the cars going when they hit each other? Accident Leading question: “About how fast were the cars going when they smashed into each other?” Memory construction

43. Loftus Results Word Used in Question Average Speed Estimate smashed collided bumped hit contacted 41 m.p.h. 39 m.p.h. 38 m.p.h. 34 m.p.h. 32 m.p.h.

44. Eyewitness Testimony Recall not an exact replica of original events What you recall is a construction built and rebuilt from various sources Often fit memories into existing beliefs or schemas Schema—mental representation of an object, scene or event – Example: schema of a countryside may include green grass, hills, farms, a barn, cows, etc. 60 Minutes: Eyewitness Testimony http://www.youtube.com/watch?v=97DSyF_Z3Do&feature=relmfu http://www.youtube.com/watch?v=WFRiDtUbeAQ&NR=1 (part 2 - use) http://www.youtube.com/watch?v=WFRiDtUbeAQ&NR=1

45. Constructive Memory Processes The Rumor Chain Leveling: simplifying story; teller makes judgments about what’s important Sharpening: highlighting/overemphasizing details the teller determines are important Assimilation: changing details to fit better with own background or knowledge

47. Factors that Influence Memory