Encoding and Retrieval in Memory Systems: A Comprehensive Overview

1. Myers’ PSYCHOLOGY (5th Ed) Chapter 9 Memory James A. McCubbin, PhD Clemson University Worth Publishers

2. Memory • Memory • persistence of learning over time via the storage and retrieval of information • Flashbulb Memory • a clear memory of an emotionally significant moment or event

3. Memory • Memory as Information Processing • similar to a computer • write to file • save to disk • read from disk • Encoding • the processing of information into the memory system

4. Memory • Storage • the retention of encoded information over time • Retrieval • process of getting information out of memory

5. Memory • Short term memory • activated memory that holds a few items briefly • look up a phone number, then quickly dial before the information is forgotten • Long term memory • the relatively permanent and limitless storehouse of the memory system

6. Encoding Effortful Automatic Encoding

7. Encoding • Automatic Processing • unconscious encoding of incidental information • space • time • frequency • well-learned information • word meanings • we can learn automatic processing • reading backwards

8. Encoding • Effortful Processing • requires attention and conscious effort • Rehearsal • conscious repetition of information • to maintain it in consciousness • to encode it for storage

9. Encoding • Ebbinghaus used nonsense syllables • TUV ZOF GEK WAV • the more times practiced on Day 1, the fewer repetitions to relearn on Day 2 • Spacing Effect • distributed practice yields better long term retention than massed practice

10. Encoding Time in minutes taken to relearn list on day 2 20 15 10 5 0 8 16 24 32 42 53 64 Number of repetitions of list on day 1

11. Encoding • Serial Position Effect • tendency to recall best the last and first items in a list

12. Encoding 90 Percentage of words recalled 80 70 60 50 40 30 20 10 0 1 2 3 4 5 6 7 8 9 10 11 12 Position of word in list

13. What do we Encode? • Semantic Encoding • encoding of meaning • including meaning of words • Acoustic Encoding • encoding of sound • especially sound of words • Visual Encoding • encoding of picture images

14. Encoding • Imagery • mental pictures • a powerful aid to effortful processing, especially when combined with semantic encoding • Mnemonics • memory aids • especially those techniques that use vivid imagery and organizational devices

15. Encoding • Chunking • organizing items into familiar, manageable units • like horizontal organization- 1776149218121941 • often occurs automatically • use of acronyms • HOMES- Huron, Ontario, Michigan, Erie, Superior • ARITHMETIC- ARat In Tom’s House Might Eat Tom’s Ice Cream

16. Encoding • Hierarchies • complex information broken down into broad concepts and further subdivided into categories and subcategories

17. Encoding (automatic or effortful) Meaning (semantic Encoding) Imagery (visual Encoding) Organization Chunks Hierarchies Encoding

18. Encoding • Forgetting as encoding failure • Information never enters the memory system • Attention is selective • we cannot attend to everything in our environment • William James said that we would be as bad off if we remembered everything as we would be if we remembered nothing

19. Attention Encoding External events Sensory memory Short-term memory Long-term memory Encoding Encoding failure leads to forgetting Encoding • Forgetting as encoding failure

20. Encoding • Forgetting as encoding failure • Which penny is the real thing?

21. Storage-Retaining Information • Sensory Memory • the immediate, initial recording of sensory information in the memory system • Iconic Memory • a momentary sensory memory of visual stimuli • a photographic or picture image memory lasting no more that a few tenths of a second • Registration of exact representation of a scene • Echoic Memory • momentary sensory memory of auditory stimuli

22. Storage-Short Term Memory • Short Term Memory • limited in duration and capacity • “magical” number 7+/-2

23. Storage-Short Term Memory Percentage who recalled consonants 90 80 70 60 50 40 30 20 10 0 3 6 9 12 15 18 Time in seconds between presentation of contestants and recall request (no rehearsal allowed)

24. Storage-Long Term Memory • Long Term Memory • virtually limitless capacity • we don't have to discard old items to remember new items • Ebbinghaus- forgetting curve over 30 days • initially rapid, then levels off with time

25. Storage-Long Term Memory Percentage of list retained when relearning 60 50 40 30 20 10 0 1 2 3 4 5 10 15 20 25 30 Time in days since learning list

26. Storage-Long Term Memory • How does storage work? • Karl Lashley (1950) • rats learn maze • lesion cortex • test memory • Synaptic changes • Long-term Potentiation • increase in synapse’s firing potential after brief, rapid stimulation • Strong emotions make for stronger memories • some stress hormones boost learning and retention

27. Storage-Long Term Memory • Amnesia- the loss of memory • Explicit Memory • memory of facts and experiences that one can consciously know and declare • hippocampus- neural center in limbic system that helps process explicit memories for storage • Implicit Memory • retention without conscious recollection • motor and cognitive skills • dispositions- conditioning

28. Hippocampus Storage-Long Term Memory • MRI scan of hippocampus (in red)

29. Storage- Long Term Memory Subsystems Types of long-term memories Explicit (declarative) With conscious recall Implicit (nondeclarative) Without conscious recall Personally experienced events (“episodic memory”) Dispositions- classical and operant conditioning effects Facts-general knowledge (“semantic memory”) Skills-motor and cognitive

30. Retrieval • Recall • the ability to retrieve info learned earlier and not in conscious awareness-like fill in the blank test • Recognition • the ability to identify previously learned items-like on a multiple choice test

31. Retrieval • Relearning • amount of time saved when relearning previously learned information • Priming • activation, often unconsciously, of particular associations in memory

32. Retrieval Cues • Reminders of information we could not otherwise recall • Guides to where to look for info • Context Effects • memory works better in the context of original learning

33. Retrieval Cues Percentage of words recalled 40 30 20 10 0 Water/ land Land/ water Land/ water Land/ land Different contexts for hearing and recall Same contexts for hearing and recall

34. Retrieval Cues • Deja Vu- (French) already seen • cues from the current situation may subconsciously trigger retrieval of an earlier similar experience • "I've experienced this before" • Mood Congruent Memory • tendency to recall experiences that are consistent with one’s current mood • memory, emotions or moods serve as retrieval cues • State Dependent Memory • what is learned in one state (while one is high, drunk or depressed) can more easily be remembered when in same state

35. Retrieval Cues • After learning to move a mobile by kicking, infants had their learning reactivated most strongly when retested in the same rather than a different context (Butler & Rovee-Collier, 1989).

36. Attention Encoding External events Sensory memory Short-term memory Long-term memory Encoding Retrieval Retrieval failure leads to forgetting Retrieval • Forgetting can result from failure to retrieve information from long-term memory

37. Forgetting-Interference • Learning some items may disrupt retrieval of other information • Proactive(forward acting) Interference • disruptive effect of prior learning on recall of new information • Retroactive (backwards acting) Interference • disruptive effect of new learning on recall of old information

38. Forgetting-Interference • Motivated Forgetting • people unknowingly revise history • Repression • defense mechanism that banishes anxiety-arousing thoughts, feelings, and memories • Positive Transfer • sometimes old information facilitates our learning of new information • knowledge of Latin may help us to learn French

39. Forgetting • Forgetting can occur at any memory stage • As we process information, we filter, alter, or lose much of it

40. Sensory memory - the senses momentarily register amazing detail Short term memory - a few items are both noticed and encoded Long-term storage - Some items are altered or lost Retrieval from long-term memory - depending on interference, retrieval cues moods and motives, some things get retrieved, some don’t Forgetting

41. Memory Construction • We filter information and fill in missing pieces • Misinformation Effect • incorporating misleading information into one's memory of an event • Source Amnesia • attributing to the wrong source an event that we experienced, heard about, read about, or imagined (misattribution)

42. Memory Construction • People fill in memory gaps with plausible guesses and assumptions • Imagining events can create false memories • Children's eyewitness recall • Child sexual abuse does occur • Some innocent people suffer false accusations • Some guilty cast doubt on true testimony

43. Memory Construction • Memories of Abuse • Repressed or Constructed? • Child sexual abuse does occur • Some adults do actually forget such episodes • False Memory Syndrome • condition in which a person’s identity and relationships center around a false but strongly believed memory of traumatic experience • sometimes induced by well-meaning therapists

44. Memory Construction • Most people can agree on the following: • Incest happens • Forgetting happens • Recovered memories are commonplace • Memories recovered under hypnosis or drugs are unreliable • Memories of things happening before age 3 are unreliable • Memories, whether false or real, are upsetting

45. Improve Your Memory • Study repeatedly to boost recall • Spend more time rehearsing or actively pondering material • Make material personally meaningful • Use mnemonic devices • associate with peg words- something already stored • make up story • chunk-acronyms

46. Improve Your Memory • Activate retrieval cues- mentally recreate situation and mood • Recall events while they are fresh- write down before interference • Minimize interference • Test your own knowledge • rehearse • determine what you do not yet know