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MEMORY: MODELS, STRUCTURES, PROCESSES

MEMORY: MODELS, STRUCTURES, PROCESSES

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MEMORY: MODELS, STRUCTURES, PROCESSES

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  1. MEMORY: MODELS, STRUCTURES, PROCESSES

  2. AcknowledgmentsPlease note that some of the figures and pictures included were adapted from:http://www.mtsu.edu/~sschmidt/Cognitive/outline.htmlwww2.una.edu/psychology/py385/goldstein%20chp5-1.ppt psy-www-old.psy.ed.ac.uk/Local/Lectures/Psych3blogie/Level3Lecture6.ppthttp://www.scottsdalecc.edu/ricker/psy101/readings/section_2/images/amnesia.jpeghttp://www.ars.usda.gov/is/graphics/photos/fruitsimages.new.htmhttp://ausmall.com.au/freegraf/freegrfa.phphttp://www.dreamstime.com/free-photoshttp://www.allaboutyourownwebsite.com/free_graphics.shtml#photoshttp://desktoppub.about.com/od/freeclipart/Free_Clip_Art.htmhttp://images.google.com/images?hl=en&q=freeimages.com&gbv=2&aq=9s&oq=free+imageshttp://www.rediff.com/ishare/photohttp://images.google.pl/imageshttp://www.free-stuff.me.uk/freehttp://commons.wikimedia.org/wiki

  3. Defining memory • Memory – the means by which we draw on our past experiences to use the information in the present • Memory as a process – it refers to the dynamic mechanisms associated with retaining and retrieving information about past experience • Three common operations of memory: 1. encoding – transformation of sensory data into a form of mental representation 2. storage – keeping encoded information in memory 3. retrieval – pulling out or using information stored in memory

  4. Deficient memory: amnesia • Amnesia = severe loss of memory • Anterograde amnesia • difficulty in remembering things that happened from the time of a trauma onward • Retrograde amnesia • loss of one’s purposeful memory for events prior to a trauma

  5. Amnesia • - a case reported by Russell and Nathan (1946): a man suffered from amnesia after a motorbike accident in 1933, • upon questioning, he gave the date as February 1922, and believed himself to be a schoolboy; he had no recollection of the intervening years, but then gradually recovered his memories, starting from the more distant past and progressing up to the time of the trauma • by 10 weeks after the accident, he was able to recall everything that had happened to him up to a few minutes prior to the accident

  6. Infantile amnesia • TASK- write down 10 concrete words that come to your mind (e.g., sea, shop, dog, etc.) • Swap your list of words with the person sitting next to you. • Look at each word and try to recall the EARLIEST memory connected with the object it denotes (e.g., when you see the word DOG try to recall when you first saw a dog as a small child, or when you see the word SOUP, think of the very first memory you have as a small child eating soup); put your approximate age next to each memory

  7. Infantile amnesia • Infantile amnesia - inability to recall events that happened when we were very young • generally, we can remember little or nothing prior to the age of 3 • but: memories of significant events (births, deaths) • the accuracy of childhood memories is questionable (covert and overt suggestions about the material)

  8. Outstanding memory: mnemonists • Mnemonists = demonstrate extraordinary memory ability, usually based on a special technique for memory enhancement • Examples: • „S.” reported by Alexander Luria (1968); • his memory had no limits, • could reproduce extremely long strings of words even after 15-16 years, • depended on the mnemonic of the visual imagery, • converted material into visual images (RED-> a man in a red shirt coming toward him; 3- a gloomy person; 6- a man with a swollen foot)

  9. Outstanding memory: mnemonists • synesthesia – experiencing sensations in a sensory modality different from the sense that is physically stimulated (e.g., automatically converting a sound into a visual image) • V.P. (Hunt & Love, 1972) could memorize long strings of material (rows and columns of numbers), • relied on verbal translations, • memorized numbers by transforming them into dates, and then thought about what he had done on that day • S.F. (Ericsson, Chase, and Faloon, 1980) remembered long strings of numbers by segmentingthem into groups of 3 or 4 digits and encoding them as running times for different races (he was an experienced long-time runner) • developed his mnemonic ability after 200 practice sessions distributed over the period of 2 years- • increased his memory for digits more than 10-fold (he started as a regular subject with the average recall of about 7 digits)

  10. Outstanding memory: mnemonists • the work with S.F. suggests that a person with a fairly typical level of memory can be converted into one with quite an extraordinary memory (with a great deal of concerted practice) • Disadvantages of a mnemonic memory: • synesthesia may interfere with the listening abilities (voices cause blurs of sensations), • abstract concepts (cannot be visually imagined)- difficult to understand

  11. Tasks used for measuring memory Recall = a task to produce a fact, a word, or other item from memory (eg. fill-in-the-blanks tests), based on expressive knowledge • serial – in the exact order in which items were presented • free – random order • cued – first presentation of items in pairs, then only one item to recall its mate

  12. Tasks used for measuring memory • Recognition = a task to select or identify an item as being one that you learned previously (eg. multiple choice, true-false), usually better than recall, based on receptive knowledge

  13. explicit tasks –requiring a conscious recollection – we are to recall or recognize words, facts, or pictures from a particular prior set of items implicit tasks – performance is assisted by previous experiences which we do not consciously try to recollect, eg. word-completion tasks (m_m_ _ _) we perform better when the word has been presented recently (memory priming), even amnesiacs perform well on cued-recall tasks

  14. Tasks involving procedural vs. declarative knowledge • procedural knowledge – „knowing how” skills, eg. how to drive a car • declarative knowledge – „knowing that”, factual information, e.g. your name, address etc. • amnesiacs perform well on procedural memory tasks • they may also improve their achievement in declarative memory tasks if they involve some procedural elements (eg. puzzles, motor skills)

  15. Traditional model of memory(Atkinson and Schiffrin) • William James (1890): • primary memory (for temporary information currently in use) • secondary memory (for permanent store of information). • Richard Atkinson and Richard Shiffrin (1968) distinguished 3 memory stores: • sensory store – capable of storing limited amounts of information for very brief periods of time • short-term store – capable of storing information for longer periods of time, but also relatively limited • long-term store – capable of storing information for very long periods of time, perhaps even indefinitely

  16. A three-store model of memory

  17. The three-stores model: Sensory store • sensory store is the initial repository of information that then enters short-term and long-term stores • strong evidence for an iconic store – visual sensory register where information is stored in the form of icons (visual images, visual persistence)

  18. Sensory store • keeps accurate record of sensory information for brief time to select important stimuli for later processing • produces modality specific cognitive codes • short duration of information • visual (iconic): 200-400 milliseconds • auditory (echoic): 2.5 - 3 seconds • unattended stimuli decay

  19. The three-stores model: Sensory store • Sperling’s discovery (1960) • how much information can we encode in a single brief glance at a set of stimuli? • flashed an array of letters and numbers on a screen for 50 milliseconds • subjects were to recall the symbols and their location

  20. H B S T A H M G E L W C

  21. SPERLING’S TASK • subjects always recalled about 4 symbols • to measure what the subjects saw, Sperling first used a whole-report procedure • then a partial-report procedure-> report one line of the digits only

  22. L W T S K A N M O V P Z

  23. SPERLING’S TASK • partial-report procedure-suggested that the iconic store can hold about 9 -12 items, and then it decays rapidly (when cued 1 second later, the recall was down to 4 or 5 of the 12 items) • we are subjectively unaware of such a fading phenomenon, because we are rarely exposed to such short stimuli and we are unable to distinguish what we see in iconic memory from what we actually see in the environment; • disadvantage of the method: output interference (verbally reporting multiple symbols interferes with iconic memory)

  24. SPERLING’S TASK

  25. Sensory store – subsequent refinement • Averbach & Coriell (1961) • subjects reported only a single letter at a time to minimize output interference; • with reduced output interference the capacity of iconic store may be of as many as 12 items(75% of the 16 letters presented in the original display) • Another experiment suggested that iconic memory can be erased- visual sensations need to disappear rapidly for us to function well in the environment. • They used backward visual masking – placement of one stimulus where another one had previously appeared.

  26. Sensory store – subsequent refinement • Another experiment suggested that iconic memory can be erased • visual sensations need to disappear rapidly for us to function well in the environment. • They used backward visual masking – placement of one stimulus where another one had previously appeared.

  27. F

  28. L

  29. Sensory store – subsequent refinement • presentation within 100 milliseconds superimposes the mask on the letter (e.g. „F” followed by „L” would be „E”) • at longer intervals the mask erased the original stimulus (e.g. „F” followed by „L” would be „L”) • at still longer intervals between the target and the mask, the mask no longer interfered-> the target information had already been transferred to more durable memory store (run a demo on Backward Masking-Consciousness)

  30. The short-term store • memory for matters of seconds (sometimes of up to a couple of minutes) • holds a few items and some control processes that regulate the flow of information to and from long-term store • the recall is influenced by e.g. the number of syllables pronounced with each item, the more syllables the fewer items recalled • Miller (1956) – capacity of the short-term store is of 7 items +/- 2 (words or digits or chunks of numbers)

  31. The short-term store • Stores codes: Acoustic, Verbal, Semantic • Longer Duration of information: • Unrehearsed Material: ~30 seconds • Rehearsal builds representation into LTS • Unattended Stimuli Fade: Decay, Interference

  32. The long-term store • keeps memories over long periods of time, perhaps indefinitely, we rely on it heavily • it is impossible to establish its capacity • Penfield (1955, 1969): performed operations on epileptic patients using electrical stimulation of certain parts of the cerebral cortex, patients recalled remote memories  long-term memories are permanent • criticism of Penfield’s findings: only few of his many patients had remote memories, was it really recalling or just inventing? • study on memory for names and faces by Bahrick, Bahrick and Wittlinger (1975) – names and photos of former classmates, good recognition and matching results even after many years • perma-store (Bahrick) = long-term storage of some information (foreign language, mathematics)

  33. Long Term Memory • Permanent store, unlimited capacity • Information in LTM (Bower, 1975) • Knowledge of words, language • Our spatial model of the world • Knowledge of physical laws • LTM storage and structure: Info. coded acoustically, visually, semantically • Storage: Copy information from STS→LTS • Retrieval: Copy information from LTS→STS • LTS codes are permanent • Interference from other LTS code may prevent retrieval

  34. Long Term Memory • Tulving (1972) proposed a distinction into: • semantic memory = general world knowledge, facts that are not unique to us, without any temporal context (historical events, literary and historical figures, the ability to recognize family, friends, info learned at school • episodic memory = personally experienced events or episodes, temporal context is crucial (also called autobiographical memory) • Acc. to Tulving, episodic memory requires three elements: • a sense of subjective time • autonoetic awareness (ability to be aware of subjective time) • a „self” that can travel in subjective time

  35. Semantic vs. episodic memory • Tulving’s findings are supported by neurological investigation and cognitive research (K.C. – lack of autonoetic consciousness) • suffered closed-head injury at 30 • intact language, intelligence, reading, writing, thought processes; knowledge of school subjects, • knows many objective facts concerning his own life (date of birth, address, etc.) • BUT: amnesia for personal experiences (covering whole life); he cannot „time travel” either to the past or to the future

  36. Long Term Memory

  37. Larry Squire’s (1986, 1993) taxonomy of memory

  38. Long Term Memory • Declarative (explicit, conscious): “Knowing that” • measured by RECALL & RECOGNITION • Episodic memory: events • autobiographical—personal • Semantic- knowledge about the world • fairly constant knowledge structure • information about language

  39. Long Term Memory • -Nondeclarative (implicit, procedural, unconscious, nonintentional): “Knowing how” (e.g.knowing how to ride a bicycle, ability to use language) • classical conditioning • emotional conditioning • priming

  40. Levels of processing (LOP) • Craik and Lockhart (1972) • there is no specific number of stores • there are an infinite number of levels of processing at which items can be encoded, with no boundaries between one level and the next • the level of storage of information depends on how it is encoded. • the deeper the level of processing, the higher the probability that an item may be retrieved.

  41. Levels of processing (LOP) Is the word (TABLE) written in capital letters? PHYSICAL ACOUSTIC Does the word (CAT) rhyme with MAT? Is the word (DAFFODIL) a type of plant? SEMANTIC

  42. Levels of processing (LOP) • self-reference effect(Rogers, Kuiper, Kirker, 1977) – subjects show high levels of recall when asked to relate words meaningfully to themselves • self-reference effect - connected with self-schema = an organized system of internal cues regarding ourselves, our attributes and personal experiences • we encode and organize information related to ourselves better than about other topics • criticism of LOP – circular definition, paradoxes in retention, strategies that use rhymes produce better retention than those based on semantics

  43. Working memory (Baddely & Hitch, 1974; Baddeley, 1992) • alternative explanation to passive STM • WM active in cognitive processing • STM actually a component of WM • place where cognitive operations are carried out

  44. Working memory • working memory comprises: • visuospatial sketchpad – briefly holding visual images • articulatory (phonological) loop – briefly holds inner speech for verbal comprehension and acoustic processing • central executive – coordinates attentional activities and governs responses, moves items in and out of short-term memory and integrates information arriving from the senses and long-term memory

  45. Working memory • part of long-term memory • comprises short-term memory • holds only the most recently activated portion of long-term memory and moves the activated elements into and out of temporary memory storage • governs the processes of memory (encoding and integrating information into meaningful arrangements, which can be reformatted later)

  46. Major components: Central Executive • central pool of mental resources • controlling attentional mechanism • coordinates activities with subsystems • initiates control and decision processing, language comprehension, • transfers information to LTS via rehearsal

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