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Memory The ability of the mind or of an individual or organism to retain learned information and knowledge of past events and experiences and to retrieve it William James on Memory “The art of remembering is the art of thinking. When we wish to fix a new thing in either our own mind or a pupil's, our conscious effort should not be so much to impress and retain it as to connect it with something else already there. The connecting is the thinking; and, if we attend clearly to the connection, the connected thing will certainly be likely to remain within recall.” Connect to Remember 10 names you should know Atkinson & Shiffrin Baddeley, Alan Bartlett, Frederic Craik & Lockhart Ebbinghaus, Hermann Galton, Francis Jacobs, Joseph James, William Loftus, Elizabeth Miller, George New Thinking Early experiences have decisive impact Brain development is non-linear: There are optimum times for acquiring different kinds of knowledge and skills Brain development dependant on interplay between genes born with & experiences Age three, brains twice as active as adult. Activity drops off in adolescence. Early interactions not only create context, directly affect way brain is “wired” Brain grows and continues development through death- provided the right conditions are met. Memory in the Brain Image shows what regions in subject's brain were involved in memory task. Improves understanding of "working memory" Brain areas: • Pre-frontal cortex--retrieval & working memory • Hippocampus & other parts of Thalamus--longterm memories • Amygdala--emotional events, fear conditioning • Occipital & Temporal Lobes--visual memories Sir Frederic Charles Bartlett (1886-1969) was British psychologist One of forerunners of cognitive psychology famous study cast considerable light on formation of memory. Composed short fable called The War of the Ghosts to test memory. Could you recall events? Kenneth Craik 1943 wrote The Nature of Explanation. concept of mental models, mind forms models of reality and uses them to predict similar future events. One of earliest practitioners of cognitive science. R.S. Lockhart Principles: 1. The greater the processing of information during learning, more it will be retained and remembered. Practice,Practice,Practice! 2. Processing will be automatic unless attention is focused on a particular level. Three Stages of Memory 7 items Hermann Ebbinghaus pioneered experimental study of memory, discovered forgetting curve / learning curve. A typical graph of the forgetting curve shows that humans tend to halve their memory of newly learned knowledge in a matter of days or weeks unless they consciously review the learned material. Ebbinghaus Learning Curve Francis Galton (1822-1911) British Psychologist •Coined term "eugenics" and phrase "nature versus nurture“ • Discovered that fingerprints were an index of personal identity •Advocated human breeding restrictions to curtail breeding of 'feeble-minded' The first systematic experimental work to be done on STM was by Joseph Jacobs (1887) He devised a technique called ‘Digit Span’ which has played an important role in memory research Most people can manage 6 or 7 digits, but there is a large range (4-10+) This can be improved by speaking them aloud or by chunking http://www.dushkin.com/connectext/psy/ch07/digitspan.mhtml The Nature of Memory •Encoding: Gets information into memory. •Storage: Retains information over time. •Retrieval: Take information out of storage. Encoding first of three stages in memory process, involving processes associated with receiving or registering stimuli through senses and modifying that information. Levels of Processing Theory: States that memory is continuum from shallow to deep. Shallow Level: Physical and perceptual features analyzed. Intermediate Level: Stimulus is recognized and labeled. Deepest Level: Semantic, meaningful, symbolic characters used. Sensory Memory Storage Holds information from world in original form only for instant. •Echoic Memory: Auditory memory lasts several seconds. Iconic Memory: Visual memory lasts about 1/4 second. George Sperling 1960 documented existence of iconic memory (sensory memory subtypes) with free-recall & cued-recall experiments Short Term (Working) Memory Storage Miller's Magic Number George Miller's classic 1956 study found amount of information which can be remembered on one exposure is between five and nine items, Applying range of +2 or -2, number 7 became known as Miller's Magic Number, number of items held in Short-Term Memory working memory was referred to as short-term memory, primary memory, immediate memory, operant memory, or provisional memory Maintenance Rehearsal Encoding Sensory Sensory Memory Input Attention Working or Short-term Memory Long-term memory Retrieval Working Memory Alan Baddeley and Graham Hitch proposed Model of Working Memory 1974 • Visuospatial sketch pad - holds visual and spatial info • Phonological loop - holds verbal information • Central executive - coordinates all activities of working memory; brings new information into working memory from sensory and long-term memory Visuospatial Sketch Pad Central Executive Phonological Loop Episodic buffer • In 2000, Baddeley added fourth component called 'episodic buffer'. • third slave system, dedicated to linking information across domains to form integrated units of visual, spatial, and verbal information with time sequencing (or chronological ordering) • memory of a story or a movie scene. • assumed to have links to long-term memory and semantical meaning Long-Term Memory Maintenance Rehearsal Encoding Sensory Input Attention Sensory Memory Working or Short-term Memory Long-term memory Retrieval relatively permanent type of memory holds huge amounts of information long period of time Long-Term Memory Long-term Memory Explicit Memory Episodic Memory experiences Semantic Memory facts Implicit Memory Procedural Memory skills Classical Conditioning learning Priming cues Explicit Memory Episodic Memory Semantic Memory •Explicit Memory: conscious recollection of information, such as specific facts or events •Semantic Memory: person’s knowledge of world •Episodic Memory: retention of information about the where and when of life’s happenings •Prospective Memory: Remembering information about something in future time-based or event-based. Retrieval – Explicit Memory • Context-Dependent Memory – more successful at retrieving if in same environment in which we stored them (cues) Olfactory is strongest • State-Dependent Memory – more successful at retrieving if in same mood as when we stored them Implicit Memory Classical Conditioning Procedural Memory Priming •Implicit Memory: behavior is affected by prior experience without that experience being consciously recollected •Classical Conditioning •Procedural Memory: Memory for skills. •Priming: Information that people already have in storage is activated to help them remember new information better and faster Declarative vs. procedural memory • Declarative memory (explicit memory): – – – – facts dates events Hippocampus is critical • Procedural memory (non-declarative/implicit): – how to perform an act (ride a bicycle) – basal ganglia (dorsal striatum / caudate-putamen) is critical Atkinson-Shiffrin model, Multi-store model or Multi-memory model 1968 human memory involves sequence of three stages: Added later Original Model Memory Improvement Donald Hebb argued that it was doubtful that a chemical process could occur fast enough to accommodate immediate memory, yet remain stable enough to accommodate permanent memory. Hence, the present theory of three storage areas. Memory Measures • Recognition specific cue is matched against LTM • Recall general cue used to search memory • E.g. define term “operant conditioning” • Relearning learns material second time. Memory Serial Position Effect: tendency for items at beginning and end of list to be recalled more readily. Probability of Recall 1.00 Primacy Effect .50 .00 1 5 Recency Effect 10 Serial Position of Item 15 Theories of Forgetting • Decay theory: memory trace fades with time • Interference theory information competes for retrieval • Proactive interference: old information interferes with recall of new information • Retroactive interference: new information interferes with recall of old information • Motivated forgetting: loss of painful memories • Encoding failure: information never encoded properly from STM to LTM and thus forgotten. • Retrieval failure: information still in LTM, but can’t be recalled - retrieval cue is absent “Trace Consolidation Theory” • memory hasn’t had time to become firmly established • Consolidation is a process lasting for several hours, or possibly even days, which fixes information in long-term memory. • Recently formed memories still being consolidated are especially vulnerable to interference and forgetting. most popular theory among neuroscientists Memory Disorders •Korsikoff’s Syndrome (chronic alcoholics), Alzheimer’s, patients like H.M. with hippocampal/thalamus damage, Amnesia • Severe epilepsy, treated with surgery to bilaterally remove medial temporal lobes. • Operation 9/1953, 27 years old • Tested 4/1955, age 29 – Reported date 3/1953, age of 27 – No memories since operation – IQ better than pre-op (112) – Fewer seizures • Profound failure to create new memories – Can’t find new home (after 10 mos.) – Can’t remember new people, names, tasks H.M.: • “Right now, I’m wondering, Have I done or said anything amiss? You see, at this moment everything looks clear to me, but what happened just before? That’s what worries me. It’s like waking from a dream; I just don’t remember.” • “…Every day is alone in itself, whatever enjoyment I’ve had, and whatever sorrow I’ve had.” • Deficits • Complete loss of episodic memory – Events/People since operation • Location of new home • Rey figure: copy but not recalled • Semantic memory – Language frozen in 50’s – Exceptions: Ayatollah, rock ‘n roll HM Amnesia • Amnesia - forgetting produced by brain injury or trauma – Retrograde amnesia problems with recall of information prior to trauma – Anterograde amnesia problems with recall of information after trauma Retrograde amnesia Anterograde amnesia Point of Trauma Eyewitness Testimony • Primarily because of constructive nature of memory, reliability of eyewitness testimony is questioned. DNA Lineups Can Be Biased Jurors Believe, Not Reason Repressed Memories Hotly Debated • Reliability called into question due to: – Constructive Recall: according to schema theory of memory organization long-term memories are stored as parts of schemas (cognitive structures used for organizing information about events). – Ulric Neisser suggested there are times when memories are distorted by adding or changing some of details in order to fit with schema. – Source amnesia: explicit memory disorder in which someone can recall certain information, but does not know where or how it was obtained. – Sleeper effect: Carl Hovland refers to "hidden" effect of propaganda message even when it comes from discredible source. Elizabeth Loftus Works on human memory and how it can be changed by facts, ideas, suggestions and other forms of post-event information. work is controversial has direct application in law and counseling. 1992 by False Memory Syndrome Foundation (FMSF) theory that some adults who remember instances of abuse from childhood may be mistaken .Foundation hypothesizes that so-called false memories may be result of recovered memory therapy, another term coined by the FSMF in the early 1990s. Pick a good elephant Positive Pollyanna Principle Pollyanna principle or Pollyannaism •people agree with positive statements describing them. •sometimes called positivity bias. •phenomenon similar to Forer effect IBM term, stating “machines should work, people should think”(aka. personal validation fallacy or Barnum effect after P. T. Barnum) Von Restorff Effect also called the isolation effect, predicts that item that "stands out like a sore thumb" (called distinctive encoding) more likely remembered Zeigarnik Effect people remember uncompleted or interrupted tasks better than completed ones Ways to Improve Working Memory •Chunking •Rehearsal H.Ebbinghaus = meaningful words easier to recall • takes 10 times more exposure to material in order to learn if words are random • rhymes, song and stories help • organize: Most important first = primacy effect Most important last = recency effect • put it in context http://www.youtube.com/watch?v=FBpXMLDMDf0