Memory

1. Memory Chapter 10

2. Memory • Reconstructing the past • Memory and the power of suggestion • In pursuit of memory • The three-box model of memory • The biology of memory • How we remember • Why we forget • Autobiographical memories

3. Reconstructing the Past • The Manufacture of Memory • The Fading Flashbulb • The Conditions of Confabulation

4. The Manufacture of Memory • Memory • The capacity to retain and retrieve information. • Memory is a reconstructive process. • Recovering a memory is not playing a videotape. • Memory involves inferences that fill in gaps in recall. • We are often unaware we have made such inferences. • Source Amnesia • The inability to distinguish what you originally experienced from what you heard or were told later about an event.

5. The Fading Flashbulb • Some unusual, shocking or tragic events hold a special place in memory. • These memories were called Flashbulb memories because the term captures the surprise, illumination & photographic detail that characterize them. • Even flashbulb memories have errors.

6. The Conditions of Confabulation • Confabulation • Confusion of an event that happened to someone else with one that happened to you, • or a belief that you remember something when it never actually happened.

7. Confabulation is most likely when: • You have thought about the event many times. • The image of the event contains many details. • The event is easy to imagine. • You focus on emotional reactions to the event rather than what actually happened.

8. Memory and the Power of Suggestion • The eyewitness on trial • Children’s testimony

9. The Eyewitness on Trial • Eyewitnesses are not always reliable. • Factors which influence accuracy • Cross race identification • Question wording • Crashed versus hit • Misleading information

10. Children’s Testimony • Under what conditions are children more suggestible? • Being very young • When interviewers expectations are clear • When other children’s memories for events are accessible

11. Children’s Testimony Social Pressure, False Allegations • If asked if a visitor committed acts that had not occurred, few 4-6 year olds said yes. • 30% of 3-year olds said yes • When investigators used techniques taken from real child-abuse investigations, most children said yes.

12. In Pursuit of Memory • Measuring memory • Explicit memory • Implicit memory • Models of memory

13. Explicit Memory • Conscious, intentional recollection of an event or of an item of information. Assessed through: • Recall • The ability to retrieve and reproduce from memory previously learned material. • Recognition • The ability to identify previously encountered material.

14. Implicit Memory • Unconscious retention in memory, as evidenced by the effect of a previous experience or previously encountered information on current thoughts or actions. Assessed through: • Priming • a person reads or listens to information and is later tested to see whether the information affects performance on another type of task. • Relearning • compares the time required to relearn material with the time used in the initial learning of the material.

15. The Three-Box Model of Memory • Sensory memory: Fleeting impressions • Short-term memory: Memory’s scratch pad • Long-term memory: Final destination • Parallel distributed processing (PDP) model: an alternative model of memory in which knowledge is represented as connections among thousands of interacting processing units, distributed in a vast network, and all operating in parallel.

16. Three-Box Model of Memory

17. Sensory Memory: Fleeting Impressions • A memory system that momentarily preserves extremely accurate images of sensory information. • Pattern Recognition • The identification of a stimulus on the basis of information already contained in long-term memory. • Information that is not quickly passed to short term memory is gone forever.

18. Short-term: Memory’s Scratch Pad • In the three-box model of memory, a limited capacity memory system involved in the retention of information for brief periods; it is also used to hold information retrieved from long-term memory for temporary use. • Working memory • A memory system which includes STM and mental processes that control retrieval of information from LT memory and interpret that information appropriately for a given task. • Chunk • Meaningful unit of information which may be composed of smaller units.

19. The Value of Chunking • You have 5 seconds to memorize as much as you can. • Then, draw an empty chess board and reproduce the arrangement of pieces.

20. Long-term memory: Final Destination • The memory system involved in the long term storage of information • One way information is organized is in semantic categories (i.e., animals).

21. Conceptual Grid

22. Contents of Long-Term Memory • Procedural memories • Memories for performance of actions or skills. • “Knowing how.” • Declarative memories • Memories of facts, rules, concepts, and events; includes semantic and episodic memory. • “Knowing that” • Examples include semantic and episodic memories.

23. Contents of Long-Term Memory • Semantic memories • General knowledge, including facts, rules, concepts, and propositions. • Episodic memories • Personally experienced events and the contexts in which they occurred.

24. Serial-Position Effect • The tendency for recall of first and last items on a list and to surpass recall of items in the middle of the list.

25. The Biology of Memory • Forming a memory involves chemical and structural changes at the level of neurons. • In short-term memory, changes within neurons temporarily alter the neuron’s ability to release transmitters. • In long- term memory, long-term potentiation or a long-lasting increase in the strength of synaptic responsiveness occurs. • Most researchers believe this is the process underlying learning and memory yet exact biochemical and molecular changes still debated.

26. Consolidation • Process by which a long-term memory becomes durable and stable.

27. Locating Memories • New brain imaging and testing shows us that: • During short-term memory tasks, areas of the frontal lobes show activity. • Long- term memory tasks, the hippocampus. • Encoding of pictures and words, prefrontal cortex and areas adjacent to the hippocampus. • Procedural memories, specific changes to cerebellum. • Formation of long-term memories, cerebral cortex.

28. Hormones and Memory • Hormones released by the adrenal glands during stress and emotional arousal enhance memory. • Moderate levels are optimal: memory can suffer if animals are given very high doses of adrenal hormones. • These may affect memory by stimulating an increase in the level of glucose in the bloodstream.

29. How We Remember • Effective Encoding • Rehearsal • Mnemonics

30. Rehearsal • Maintenance Rehearsal • Rote repetition of material in order to maintain its availability in memory. • Elaborative Rehearsal • Association of new information with already stored knowledge and analysis of the new information to make it memorable.

31. Deep Processing • In the encoding of information, the processing of meaning rather than simply the physical or sensory features of a stimulus.

32. Comparing Encoding Strategies

33. Mnemonics • Strategies and tricks for improving memory, such as the use of a verse or a formula. • Examples include: • MDAS • ROYGBIV • Thirty days hath September…

34. Why We Forget • Decay • Replacement • Interference • Cue-dependent forgetting • Psychogenic amnesia

35. Decay • Decay Theory • The theory that information in memory eventually disappears if it is not accessed; it applies more to short-term than to long-term memory.

36. Forgetting Curve • Herman Ebbinghaus tested his own memory for nonsense syllables. • Forgetting was rapid at first and then tapered off.

37. Replacement • The theory that new information entering memory can wipe out old information. • In one study, researchers showed subjects slides of a traffic accident. • The experimental group was mislead into thinking there was a stop sign instead of a yield sign. • Even after being debriefed on the purpose of the study, subjects insisted that they really saw the stop sign (Loftus et al., 1978). • The new information which came from the researchers replaced what the subjects saw.

38. Interference • Similar items interfere with one another. • Retroactive Interference • Forgetting that occurs when recently learned material interferes with the ability to remember similar material stored previously. • Proactive Interference • Forgetting that occurs when previously stored material interferes with the ability to remember similar, more recently learned material.

39. Cue-dependent Forgetting • The inability to retrieve information stored in memory because of insufficient cues for recall. • Physical state can be a memory cue. • State-Dependent Memory • The tendency to remember something when the rememberer is in the same physical or mental state as during the original learning or experience. • Mood

40. The Repression Controversy • Psychogenic Amnesia • The partial or complete loss of memory (due to nonorganic causes) for threatening information or traumatic experiences. • Repression • In psychoanalytic theory, the selective involuntary pushing of threatening or upsetting information into the unconscious.

41. When should we question recovered memories? • If person says he or she has memories of first year or two of life. • If over time the memories become more and more implausible. • If therapist used hypnosis.

42. Autobiographical Memories • Childhood amnesia: The missing years

43. Childhood Amnesia: The Missing Years • Childhood Amnesia • The inability to remember events and experiences that occurred during the first two or three years of life. • Cognitive explanations • Lack of sense of self • Impoverished encoding • A focus on the routine • Different ways of thinking about the world