General Psychology 1 Memory – Modules 23-26 April 5-7, 2005 Class #19-20 Memory Memory To a psychologist, memory is any indication that learning has persisted over time A pioneer of the scientific study of memory: Hermann Ebbinghaus (1850 – 1909) Worked as philosopher at University in Berlin Performed experiments on himself published in classic volume entitled: ‘Über das Gedächtnis’ (1885) Hermann Ebbinghaus Serial Learning Experiments A list of items presented one at a time Memorizing lists in sequence until they can be recalled perfectly in order they were presented Ran tests on himself for six years Memorized thousands of lists of nonsense syllables (ZAB, VUB, 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? Ebbinghaus' Experiments 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 Effect (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) Memory experiments of Ebbinghaus: Focus on retention of newly learnt material Invented lists of 16 nonsense syllables to minimize influence of meaningful associations and learner’s history goal: study memory in ‘pure’ form Introduced criterion for successful learning (2 errorless recitations) Introduced savings method to measure retention/forgetting of lists Memory experiments of Ebbinghaus… Other important findings 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 Memory Testing Research Methods Serial Learning Experiments These were Ebbinghaus’ experiments A list of items presented one at a time Subjects are asked to recall them in order Memorizing lists in sequence until they can be recalled perfectly Memory Testing Research Methods Free Recall In this experimental procedure the subjects are asked to recall the items presented to them in any order they wish Probably this is the simplest way to test the effects of subjects studying verbal material Murdock (1962) Used common unrelated English words and found the probability of their recall depended on their position in the list What effects do you think this researcher found??? Memory Testing Research Methods Free Recall (cont.) Glanzer and Cunitz (1966) Same type of experiment as Murdock (1962) except put certain delays into equation Like AM PM What do you think happened here? Memory Testing Research Methods Paired-Associate Learning This experiment requires subjects to learn a set of stimulus-response pairings Often, subjects are exposed to the list with the usage of a "flash-card" technique Each complete presentation of the list constitutes a trial and items are presented in a different order on each trial Most researchers consider this the most challenging type of memory testing Information Processing 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? Encoding Information in sensory stores and STM is lost unless it is encoded, or processed into long term memory… Does encoding occur in a special short term memory (Atkinson and Shiffrin Model) or in rehearsal systems? Information-processing approach to memory: Basic framework 3 stages of processing for manipulation of mental representations: Encoding (acquisition of info) Storage (retention of info) Retrieval (recovery of info) Encoding time Retrieval Information Processing: Automatic Processing Processing that doesn’t require person to consciously attend to something Information Processing: Effortful Processing How does storage of this information take place? Imagery Chunking Mnemonic devices Organizing information into meaningful units so that it can better be remembered Mental Rehearsal Maintenance Rehearsal Repeating things over and over Spacing effect Elaborate Rehearsal Involves thinking about how new material relates to information already stored in memory Information Processing Model: Atkinson & Shiffrin (1968) 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 (working memory) Long-Term Memory Sensory Memory Major function is to hold info long enough so that it can be processed Sight (usually less than a second) Sound (a little longer maybe up to 3 seconds) Also referred to as “Transient Memories” Visual sensory memory The iconic store Auditory sensory memory The echoic store Auditory Sensory Memory Several studies have shown analogous results in auditory memory… Echoic store studies often use dichotic listening Echoic memory disappears by 5 seconds Information Processing Model: Atkinson & Shiffrin (1968) Short-term memory 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 Long-term memory Infinite Testing STM Immediate Memory Span The maximum # of items you can recall perfectly after one presentation Miller (1956) 7 +/- 2 meaningful groupings Brown-Peterson Procedure A method for preventing rehearsal Counting backwards by 3’s Crowder & Morton (1969): The Suffix Effect Their directions to participants: I am going to say some numbers At some point, I will say the number zero When you hear me say zero, ignore the zero and repeat all the numbers that preceded it Their directions to participants: I am going to say some numbers When you hear the tone, ignore it and repeat all the numbers that preceded it STM Baddeley (1986) “Working memory” is the more contemporary term for short-term memory, is conceptualized as an active system for temporarily storing and manipulating information needed in the execution of complex cognitive tasks Primacy and recency effects are seen in STM Limits of working memory Phonological working memory Visual working memory STM vs. LTM STM – here we can hold only a few items very briefly LTM – relatively permanent and limitless Main differences dependence on retrieval cues differences in capacity they help in LTM; no help in STM LTM is immeasurable; STM is relatively small and easily measured (Miller, 1956) differences in duration (decay over time) LTM are not affected by the passage of time much….STM can disappear in a blink of the eye LONG TERM MEMORY Long term memory stores our knowledge of the world It enables us to recall events, solve problems, comprehend, recognize patterns, etc. (permastore) Bahrick, Bahrick, and Witlinger (1975) Memory for picture recognition and matching of names with faces of yearbook portraits was remains pretty accurate even after decades… 1. Picture Recognition Test (shown a year-book picture and asked to recall the name of the person) 2. Multiple-Choice Name Matching Test (match names with pictures) Each picture had 4 names with it – multiple choice test Bahrick, Bahrick, and Witlinger (1975) Findings 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 LONG TERM MEMORY Bahrick & Hall (1991) High school Spanish was tested 30 years later Most subjects had no use of the language since finishing the course So this was recall without intervening practice Retention seems to “level out” after very long periods of time But we don’t lose all of it – seems some memory is retained in a “permastore” Unaffected by the passage of time Interestingly, who had gotten the highest grades remembered the most 30 years later Types of Interference 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) Types of Interference Examples: Time 1 Ch. 1 Ch. 1 Time 2 Ch. 2 Ch. 2 Study French Study French Study Sp. Study Sp. Test Ch. 2 Ch. 1 Recall Sp. Recall Fr. Interference Ch. 1 pro w/ch2 Ch. 2 ret w/ch1 Fr. pro. w/Sp Sp. ret. w/Fr Some Memory Distinctions Procedural memory A memory of how to do something Fix a tire, ride a bike, bake a cake, etc. Declarative memory The ability to state a fact Such as names or events, etc. Types of Declarative Memory Semantic Memory Memory of general principles knowledge of concepts and meaning Knowledge of all the information needed to use language, verbal information, visualspatial information, etc. Ex: rules of how to play chess Types of Declarative Memory Episodic Memory Memory for specific events in one’s life Autobiographical memory, time and place dependent, it conveys the conditions of occurrence Knowledge about personally experienced events Ex: when and who you played chess with the last time Flashbulb Memories These are extremely vivid episodic memories, usually attached to a surprising, significant, or vivid event Memory and Retrieval Cues How do we recall or retrieve information that is not presently in conscious awareness? Retrieval cues 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) Retrieval Cues Theories Recognition cue Identifying items from choices Bahrick (1975) Relearning cue Material already learned is relearned more quickly than new materials Memory and Retrieval Cues Moods Cue The things we learn in one emotional state are are best remembered in the same state (this is referred to as state-dependent memory) State Dependent Memory – theory that information learned in a particular state of mind (e.g., depressed, happy, somber) is more easily recalled when in that same state of mind Seems to have added effectiveness with recollections of everyday events (episodic memory) Memory and Retrieval Cues Context Effects Cue Putting yourself in the same context in which you have experienced something can help with retrieval See Gooden and Baddeley (1975) – next slide Memory and Retrieval Cues Gooden and Baddeley (1975) Group 1: Group 2: Group 3: Group 4: Listen/Recall water/land land/water water/water land/land Memory and Retrieval Cues Von Restorff Effect (1933) Cue This is our tendency to remember unusual items better than more common ones Very tall or very short people; unusual names Cued Recall Method of receiving hints to help with memory Example: initials in front of pictures Tulving and Pearlstone (1966) Category prompting led to better recall Available vs. Accessible Memories Accessible Memories These memories can be recalled or retrieved Available Memories Memories that contain learned information, but may not be retrievable (at least not at the present time) Brown and McNeil (1966) Referred to available memories as "tip-of-thetongue“ Absent Mindedness Absent mindedness means preoccupied, forgetful, inattentive Includes” “action slips” The performance of unintended actions Implications: May cause accidents – some that are fatal Workplace deaths, car crashes, etc. Absent Mindedness Problems with Methodology Experimenters can’t seem to obtain these in the laboratory settings So, instead they tell their participants to keep diary records of any action slips that they detect in their everyday lives… Do you see a problem with this… Absent Mindedness: Reason (1979) 35 volunteers asked to keep a diary of their slips of action for two weeks Some participants reported a total of 400 Reason (1979): Five Categories of Action Slips (1) Repetition errors (40%) Forgetting a action has been performed and repeating it (2) Goal switches (20%) Forgetting a goal of a sequence of actions and switching to a different goal (3) Omissions and Reversals (18%) Omitting or wrongly ordering the component actions of a sequence (4) Confusions or blends (16%) Confusing objects involved in one action sequence with those involved in another action sequence (5) Unclassified (6%) These remaining slips did not fit neatly into the other categories