PSY 190: General Psychology Chapter 7: Memory Memory An indication that learning has persisted over time; information that has been stored and can be retrieved Explicit (declarative) Memory The conscious, intentional recollection of previous experiences and specific information The ability to state a fact Such as names or events, etc. Types: Episodic Memory Memories of past experiences Semantic Memory Memories of meanings, factual information and general knowledge Implicit (nondeclarative) memory The type of memory in which previous experiences aid in the performance of a task without conscious awareness of these previous experiences Types: Procedural Memory A memory of how to do something Ride a bike, bake a cake, etc. Our memory system works much like that of a computer: Research suggests (Craik & Lockhart, 1972) that the most important determinant of memory is how extensively memory is encoded or processed when it is first received How extensively is the encoding (acquisition of information processed) during the initial formation of memory? Information in sensory stores and STM is lost unless it is encoded, or processed into long term memory Which is the real penny? 7 3 stages of processing for manipulation of mental representations: Encoding (acquisition of info) Storage (retention of info) Retrieval (recovery of info) time Encoding/FailureRetrieval? (LTM) STM How does storage of information take place? Maintenance Rehearsal Repeating things over and over Spacing effect Elaborate Rehearsal Involves thinking about how new material relates to information already stored in memory Worked as philosopher at University in Berlin Performed experiments on himself published in classic volume entitled: ber das Gedchtnis (1885) Invented lists of 16 nonsense syllables to minimize influence of meaningful associations and learners history His goal: study memory in pure form Introduced criterion for successful learning (2 errorless recitations) Nonsense syllables Ebbinghaus founded the experimental study of memory Serial Learning Experiments A list of items presented one at a time; you must recall them in order Memorizing lists in sequence until they can be recalled perfectly Ran tests on himself for six years Memorized thousands of lists of nonsense syllables (ZAB, VUB, DAL, etc.) Invented 2300 of these syllables, arranged them in random lists and tested them after various delays What problems do you see with this methodology? Serial Learning Experiments Learning to criterion Ebbinghaus would repeatedly attempt to learn the material until he achieved a perfect reproduction (every item memorized in the order originally presented) Method of savings Subtracting the number of repetitions required to relearn material to a criterion from the number originally required to learn the material to the same criterion Serial Position (Primacy/Recency) Effect Subjects are much more likely to remember items at the beginning of a list (primacy effect) and at the end of the list (recency effect) List-length effect Ease of learning and amount of information not related in linear one-to-one fashion Disproportionate increase in difficulty with more than 7 syllables Distributed practice Beneficial effects of distributed practice for repetitions Forgetting Curve Recollection of words drops dramatically during the first hour of learning Most influential historically & most comprehensive model In order for info to become firmly embedded in memory, must pass through 3 stages of mental processing: Sensory Memory Short-Term Memory (STM) Also referred to as working memory Long-Term Memory (LTM) Major function is to hold info long enough so that it can be processed Iconic Memory Visual usually less than a second Echoic Memory Auditory possibly a little longer (maybe up to 3 seconds) STM Researchers differ saying that without maintenance rehearsal something stays in STM for between 6-30 seconds. After this its either lost forever or somehow makes its way into LTM Miller (1956) 7 +/- 2 meaningful groupings Chunking Can help with STM - organizing information into meaningful units so that it can better be remembered Items can be arranged in a hierarchy superordinate, subordinate LTM Infinite (permastore) High school Spanish was tested 30 years later Participants had no use of the language since finishing the course Those who had received the highest grades remembered the most 30 years later Main differences Dependence on retrieval cues They help in LTM; no help in STM Differences in capacity LTM is immeasurable and probably limitless; STM is relatively small and easily measured Differences in duration LTM are relatively permanent; not affected by the passage of time much; STM can hold only a few items very briefly Grouping items into meaningful sequences or clusters Ericcson, Chase, & Faloon (1980) College student had an initial digit span of 7 After 230 one-hour training sessions for 2 years, he could remember up to 79 digits How did he do it? Combing the numbers with meaningful sets 3 hr 49 min 2 sec almost emergency (9 1 1) very old man, 89.3 Baddeley & Hitch (1974) These researchers updated views related to STM Refers to the system for temporarily maintaining mental representations that are relevant to the performance of a cognitive task in an activated state 1. Working memory consists of a number of parts 2. Working memory helps us manipulate information to carry out complex tasks, not just store information 23 Emotion-triggered hormonal changes can explain why we can long remember exciting or shocking events These are extremely vivid episodic memories (memory for specific events in ones life) usually attached to a surprising, significant, or vivid event + A feeling that one knows a response yet is unable to produce it Brown and McNeil (1966) Task: Retrieve the word corresponding to its provided definition e.g. A musical instrument comprising a frame holding a series of tubes struck by hammers Participants were asked to indicate if they were in a TOT state If so, guess the number of syllables and any other information about the word (e.g. first letter) Results: Participants are better at remembering associated information than they were at producing the actual word (e.g. XYLOPHONE) 25 Stimuli that help us to get information stored in LTM Seems to help the best if it taps into information that was encoded at the time of learning (encoding specificity principle) Identifying items from choices Memory for picture recognition and matching of names with faces of yearbook portraits was remains pretty accurate even after decades Bahrick, Bahrick, and Witlinger (1975) Picture Recognition Test Participants shown a year-book picture and asked to recall the name of the person Multiple-Choice Name Matching Test Participants asked to match names with pictures Each picture had four names with it Results Picture Recognition Test 50% recall after 34 years Name Matching Test 75% recall at 34 years 60% recall after 47 years The memory for faces of high school classmates seems quite durable Forgetting is rather gradual Context-Dependent Memory Dj vu Effect Putting yourself in the same context in which you have experienced something can help with retrieval Godden & Baddeley (1975) Grant et. al (1998) See next two slides Godden & Baddeley (1975) Grant et. al (1998) State Dependent Memory Information learned in a particular emotional state (e.g., depressed, happy, somber) may be more easily recalled when in that same state of mind Proactive Interference The disruptive effect of prior learning on the recall of new information (old materials increasing the forgetting of new materials) Retroactive Interference The disruptive effect of new information on the recall of previous information (new materials increasing the forgetting of old materials) Time 1 Time 2 Test Interference Study French Study Spanish Recall Spanish Proactive Study French Study Spanish Recall French Retroactive This 45 year-old woman is able to recite every day of her life since she was 14 Much in great detail This condition is referred to as hyperthymesia Click on picture for video Jill Price These are recollections of events or details of an event that did not occur Wade, Garry, Read, & Lindsay (2002) Hot air balloon study Click on picture for video After exposure to subtle misinformation, many people tend to misremember As memory fades with time, the injection of misinformation becomes easier Experiment 1 Cars were driving on what appeared to be a one-lane highway Subjects saw the same film of a car accident Later, different subjects were asked: How fast were the cars going when they smashed collided bumped contacted hit Experiment 1 Subjects estimates of speed varied with the verb they got in the question Subjects who got the stronger verb (smashed) gave higher estimates of speed Did the question about speed alter their memory of the accident? Would they remember a more severe accident than they had actually seen? Click on picture for video See next slide Elizabeth Loftus Experiment 1 Results Experiment 2 This time the accident took place at an intersection and cars were going considerably slower. The key question: Group 1: "About how fast (MPH) were the cars going when they hit each other? Group 2: "About how fast (MPH) were the cars going when they smashed into each other? Group 3: Participants in this control group were not interrogated about vehicular speed Results successfully replicated Experiment 1 as smashed group said cars were going faster than hit group Smashed: MPH Hit: 8.00 MPH Experiment 2 A week after seeing the film: Did you see any broken glass? Note: No glass was in the film 32% in the smashed group said YES Compared to 14% of the hit group The likelihood of saying YES increased as the estimates of speed increased The question about smashed was not just a leading question, it was a source of misleading information How accurate is Eyewitness Testimony??? A lot is involved here Perception can only remember what is perceived This depends on ones attention level at the time Also, may depend on top-down processing Schemas may be involved - The way we mentally represent the world Retroactive interference Something new and this might cause something old to be forgotten Integration Might involve an integration of old memories with new memories Unpublished study conducted by John Goodman at Eastern Washington University Click on picture for video Some of the slides in this presentation prepared with the assistance of the following web sites: