BHS 499-07 Memory and Amnesia

1. BHS 499-07Memory and Amnesia History of Memory

2. Three Definitions of Memory • The location where memory is stored. • The physical entity that holds the memory: • Trace • Engram • The processes used to acquire (learn), store (encode) or retrieve information.

3. Metaphors for Memory • Metaphors are used because memory is hard to understand and talk about. • Different metaphors capture different aspects of memory. • The number of metaphors tells us about the complexity of memory. • Some metaphors are better than others. • Memory is NOT like a muscle – more like a key.

4. Metaphors 1 • Recorder of experience • Wax tablet • Record player • Writing pad • Tape recorder • Video camera • Organized storage • House • Library • Dictionary

5. Metaphors 2 • Interconnections • Switchboard • Network • Jumbled Storage • Birds in an aviary • Purse • Junk drawer • Garbage can

6. Metaphors 3 • Temporal Availability • Conveyor belt • Content Addressability • Lock and key • Tuning fork • Forgetting of Details • Leaky bucket • Cow’s stomach • Acid bath

7. Metaphors 4 • Reconstruction • Rebuilding a dinosaur • Active processing • Workbench • Computer program

8. The Ancients • Plato (428?-347? B.C.) • Rationalist • Dualist – mind and body are distinct • Wax tablet metaphor (can be erased, the better the impression the more readable. • Aristotle (384-322 B.C.) • Empiricist • Laws of association • Similarity • Contrast • Contiguity

9. Modern Precursors • St. Augustine (354-430) • Advanced description of memory in the Confessions similar to modern views. • Robert Hooke (1635-1703) • Modern insights into memory, but were ignored when he was overshadowed by Newton. • Darwin and natural selection (1809-1882) • Organism changes to exploit the environment • Memory has developed to perform specific tasks.

10. Philosophy of Mind • Empiricists – extended Aristotle’s ideas • Berkeley, Locke, Mill, Hume • Knowledge through observation • Associationism • Rationalists – antagonists to empiricists • Descartes, Kant • Active involvement of the mind building ideas • Knowledge through theories (e.g., schemas)

11. Early Researchers • Ebbinghaus (1850-1909) • Nonsense syllables • PIM DAG ZOL CEK • Learning curve – massed vs spaced practice • Forgetting curve – forgetting occurs rapidly • Overlearning – studying after something is learned • Savings – decreased effort needed to relearn • Bartlett (1886-1969) • How does prior knowledge influence memory • Reconstruction is guided by schemas (concepts)

12. Gestalt Psychology • Gestalt movement • Kohler, Koffka, Wertheimer • The whole is different that the sum of its parts. • Anti-reductionistic • But did acknowledge the importance of understanding the components of thought. • Memory influenced by the configuration of elements and context. • Isomorphism of mental representation

13. Behaviorism • Behaviorism (Pavlov, Thorndike) • Psychology should be the study of observable behavior. • Reacting against introspection • Associated with the term “learning”. • Later behaviorists (like Tolman) used mental explanations and representations (maps). • Classical and operant conditioning both involve memory.

14. Verbal Learning • A behaviorist approach to the learning of verbal materials. • Developed from Ebbinghaus’s work. • Memorization is the “attachment of responses to stimuli” • Forgetting is the “loss of response availability”

15. Paired Associates Paradigm • Paired associate learning – people memorize pairs of items (BIRD-GLOVE): • A-B -- the first item is the cue and the second is the response • A-B C-D paradigm (two lists are learned) • A-B A-D paradigm (two associations learned) • A-B A-B’ paradigm (synonyms) • A-B A-Br paradigm (recombinations – hard!)

16. Early Neuroscience -- Lashley • Lashley (1890-1958) • Search for the engram • Rats learned a maze. • Lashley progressively removed larger and larger portions of rats brains, from different locations. • Memory affected more by the amount of brain tissue removed, not the location.

17. Hebb • Hebb -- The Organization of Behavior (1949) • Forerunner of computational neuroscience • Mathematical modeling of brain activity • What fires together, wires together • Signal reverberation within collections of cell assemblies followed by a change in neural interconnections

18. The Cognitive Revolution • Thought is a valid subject for study • This is the field of psychology associated with the term “memory” • Adopted the methodological rigor of the behaviorists • The computer metaphor • hardware vs. software

19. Miller’s Magic Number • George Miller • The Magical Number Seven, Plus or Minus Two (1956) – describes the capacity of short term memory • Different for verbal items and digits • Limited capacity of memory • Organization aids memory (chunking)

20. The Modal Model of Memory • Modal refers to sensory modality (way of receiving info from outside world). • Heuristic means “rule of thumb” – this is a way of thinking about memory but not to be taken literally. • The guiding framework for decades.

21. Multiple Memory Systems • Memory is not unitary but consists of several subcomponents (parts). • Tulving’s Triarchic Theory: • Episodic Autonoetic (self) • Semantic Noetic (formal knowledge) • Procedural Anoetic (automatic skills)

22. Other Classifications • Declarative vs Nondeclarative • Declarative includes episodic and semantic memory • Nondeclarative includes procedural memory, classical conditioning and priming • Explicit vs implicit • Explicit memory involves consciousness, implicit does not.

23. Current Issues • Neurological bases for memory • Impact and importance of emotion on memory • Use of multiple memory sources (fuzzy trace theories) • Embodied cognition – how our grounding in the world influences memory