2The Modal Model Basic info-processing model of memory Atkinson-Shiffrin 1968The modal modelSensory RegistryShort-TermMemoryLong-TermMemoryAttentionRehearsal
3Sensory Memory Recall Sperling Participants view a briefly presented array of letters.Tone cued participants to recall items.Change the duration between presentation of array and the recall tonePartial report suggested sensory memory is rather large but has a short duration
4Short-term memoryThe theory of STM was brought about during the cognitive revolution and is a product of the information processing perspectiveIt proposed that attended information went into an intermediate short-term memory where it had to be rehearsed (processed) before it could go into a relatively permanent long-term memory.STM is biased toward keeping recent information available and has a limited capacity to do so.Memory span - the number of elements one can immediately repeat back
5Short-term memoryIn a study of memory span, participants might rehearse digits by saying them over and over again to themselvesWith each rehearsal of an item, it was assumed there was a probability that the information would be transferred to a relatively permanent long-term memoryIf the item left short-term memory before a permanent long-term memory representation was developed, however, it would be lost foreverOne could not keep information in short-term memory indefinitely because new information would always be coming in and pushing out old information from the limited short-term memory
6Short-term memory One of the questions with STM regarded its duration What determines the duration of STM?Decay?Gradual loss of memory “strength” over time.Interference?Access to information is blocked by the retrieval of other informationOverwriting?Original memory trace is altered
7Decay Brown-Peterson Paradigm “You will not be shocked during this experiment”Study unrelated information‘T’ ‘K’ ‘B’“wood” “dog” “candy”Count backward by 3’sPrevent rehearsalVary duration of countingRecall studied items
8Brown-Peterson Interval of counting (sec.) Decay 100Proportion of correct recalls118Interval of counting (sec.)Decay(on average) memory information is accessible up to 18 seconds.
9Decay Reconcilable with sensory memory Use it or lose it.Once memory is established, decay is constantWhat constitutes “established”?Is it always ~18sec.?
10Very Rapid ForgettingSebrechts, Marsh, & Seamon (1989) based on Muter (1980)Used a modified Brown-Peterson paradigm with false trials.B-P taskAcoustic (shallow)Long E sound?SemanticIs it animate?Readingsay the stimuli aloudExp 1 regular B-P experimentExp 2 “Surprise” memory test
11Sebrechts, Marsh, Seamon Ss presented words sequentially and made a yes/no decision for each word presented or just read aloud depending on conditionCountdown followedBrown-Peterson trialWOOD KEY TIME382Recall
12Sebrechts, Marsh, & Seamon Forgetting within 6 secondsExpectation of retrieval is necessary to maintain information in memory, but also elaboration can have an effectSo again the idea of decay doesn’t provide for the whole story100B-PProportion Recalled.27.44Acoustic.35.55Semantic.52.73ReadingNon-ExpExpectLOPProportion of words recalled*Surprise Trials118Interval of counting (sec.)*They looked also at the strict scoring i.e. remembering the whole trigram,the pattern was the same but with poorer performance overall
13Interference Memory is more active Newly encountered information (if used) limits the access to previous information.Interference is often confounded with “decay”
14Interference Waugh & Norman (1965) Present a set of 16 digits at a fixed interval.1 digit per second4 digits per secondLast digit in the set served as a probe, and had previously been presented onceReport the digit that appeared after the probe digit had appeared in the list the first time (target)Manipulate the number of digits that appear between target and the probeRetention intervalIf forgetting is a function of decay (time) then there should be less recall for slower rate (16 secs) vs. faster rate (4 secs)If interference then should be little to no difference between the two
15Number of items between target & probe Waugh & Norman100Proportion Correct1 Cond.4 Cond.113Number of items between target & probeMore about the number of items that interfered rather than decayover time
16InterferenceSo the Waugh and Norman results suggest interference from additional information can disrupt memory for particular itemsTwo types of interferenceRetroactive InterferenceNew information interferes with previously learned informationProactive InterferencePreviously learned information interferes with the acquisition of new information
17InterferenceA possible explanation for interference is that when given cue, information associated with cue interferes with other info also associated with cueMore items a cue is stored with the less effective it will be in retrieving any one particular itemRecall fan effectBut along with interference as another possible explanation of forgetting, the Sebrechts et al., shows other factors will have a say in how forgetting occursExpectancy‘Depth’ of encoding
18The decline of STMThe idea of a short-term passive ‘store’ fit in with the current information processing modelsRapid forgettingTransient nature suggests different type of storeAmount of rehearsal controlled the amount transferred to LTMMore rehearsal more rememberingInfo had to ‘do time’ before getting to LTM
19The decline of STM Problems Loss similar for better learned material (initial rapid loss followed by slower loss later)Rehearsal by itself won’t determine what makes it to LTM:Chunking7 + 2What may be chunked and how chunking occurs can depend on a variety of factors and varies across individualsDepth of processing (Craik & Lockhart, 1972)The Sebrechts article was an example of how DoP had a role even if there was decaySome experiences gain immediate access to LTME.g. traumatic eventsSuch findings suggested there was more to short-term memory functioning than as a passive storage device
20Working MemoryFunction: short-term retention and manipulation of information.Active memoryIssues regarding working memoryHow long?How much?What type?CapacityForgetting curve (Brown-Peterson)Miller’s 7 +/- 2
21Baddeley Model of WM Based on perceptual codes Acoustic Visual and SpatialInformation can be retained separate from its use for a short timeCoordinating process guides the use of retained informationCentral Executive“Slave” systems“Rehearse” information for a short timePerceptually based
22Baddeley’s Model of WM Central Executive Visuo-Spatial Sketchpad PhonologicalLoopCentral ExecutiveCoordinates the Slave SystemsResponse SelectionGuides AttentionMaintains visual andspatial informationMaintains acousticinformation
23Phonological Loop Two components Phonological storeArticulatory control processSubvocal articulatory rehearsalTraces within the store decay over a period of about two seconds unless refreshed by rehearsal, a process akin to subvocalization and one that is dependent on the second component, the articulatory systemImportant for long-term phonological learninge.g., language learning
24Some evidence for the loop Phonological similarity effectPGTVCD vs. RHXKWYSimilar phono code leads to confusionIrrelevant speech effectColle & Welsh (1976): even a foreign language can interfere with immediate recall of itemsBecause of the nature of the code, the language gains access to the phono storeArticulatory suppressionOperation of the loop is disturbed if overt or cover articulation takes placeVocalization utilizes same system as subvocal rehearsal, and hence can lead to difficulty learning verbal informationWord length effectSpan decreases as the length of a word increasesLess can be rehearsed within the ~2 sec time frame
25Visuo-spatial Sketchpad Temporarily maintains and manipulates visuospatial informationPlays an important role in spatial orientation and in the solution of visuospatial problemsBoth visual (imagery) and spatial componentPossibly two different systems
26Some evidence for the sketchpad Baddeley & Lieberman (1980)Visual tracking interferes with imagery mneumonicIrrelevant picture effectSame result even from just looking at visual stimuli
27Central Executive Most complex and least understood component of WM Model suggests CE coordinates the activity of the two slave systemsOther potential rolesCoordinating retrieval strategiesSelective attentionSuppression of habitual responsesTask switchingTemporary activation of long term memoryBinding of sensory and conceptual information
28Assumptions and Predictions Slave systems are independent of each otherIt is possible to do a both a verbal task and a spatial task at the same timeExtremely difficult to do two verbal (or two spatial) tasks at the same time.Dual-Task ParadigmParticipant must perform more than one task at a timeSlave systems have limited capacitySpanSlave systems can function autonomously from the Central ExecutiveCan do “Central Executive tasks” and slave system tasks at the same timeCentral Executive coordinates information based on current goalsImplies intentional (conscious) control of WMCoordination involves many processes.
29The Episodic Buffer“A limited capacity temporary storage system that is capable of integrating information from a variety of sources”Controlled by the CEFeeds information into and retrieves information from LTMUses a common “multidimensional” codeThe Episodic Buffer makes the link between Working Memory and LTM more explicit
31Long-term memoryBasically includes anything retained that did not occur few moments earlierSource of information that does not come from the environment
32LearningStorage of information in memory as a consequence of experienceProcess of acquiring new associations among stimuli, responses and outcomes.What is Learned?How is it Learned?Associative theoriesLearningCognitive theoriesEncoding and Retrieval
33Classical Conditioning Characterized by the generalization of a fixed or previously learned behaviorResponses are elicited from stimuliUnconditioned stimulus (US)Elicits a response without trainingShockUnconditioned Response (UR)Elicited without training by a (US)Smacking whoever gave you the shockConditioned Stimulus (CS)That which through training elicits a particular responsePretty flowersConditioned Response (CR)*Response to the conditioned stimulusSmacking whoever gives you pretty flowers
34Operant / Instrumental Conditioning Based on the principle of reinforcementWhat is reinforced?What is reinforcing?Development of associations between particular responses and consequences of the response (outcomes).
35Basic Mechanisms of Operant Conditioning Behaviors have consequencesConsequences are contingent on behaviorsOrganisms adapt behavior to match contingenciesConsequences usually satisfy a “drive”Biological needMotivational needWell-being of individual
36Consequences of Behavior Reinforcement or PunishmentReinforcementConsequences of behavior increase the probability of response (behavior)PunishmentConsequences of behavior decreases the probability of responseBoth Reinforcement and Punishment can be positive or negativePositive: presentation of stimuliNegative: removal of stimuliThe result is a table of contingencies…
37Reinforcement and Punishment ResponseIncrease (rein.)Decrease (pun.)Positive Reinforcement(reward)Positive Punishment(punishment)Apply a stimulus (+)StimulusNegative ReinforcementNegative Punishment(omission)Remove a stimulus(-)
38Associative Learning Accounts for certain types of memory phenomena Memory StructureHighly practiced informationHabitual responsesStimulus generalizationAssumes memory mechanism is the same as associative mechanism (single system)
39Associative MemoryAssociative memory theory alone cannot account so well for other phenomenaFree RecallNo cueSubjective organizationVon Restorff EffectEffect of stronger memory for a salient item in a seriesSensory Memory“Direct” memory of sensory informationShort-term representationsNo PracticeComplexity of language acquisition/productionSystematic memory distortions
40Beyond associationAlthough simple associative mechanisms described by classical and operant conditioning may account for some aspects of learning, more was neededSubtle shift from learning theories to theories of memory, which emphasized knowledge representation in an information processing systemFocused on encoding and retrieval processes to help explain memory performance in a variety of settingsLevels of ProcessingEncoding specificityTransfer appropriate processing
41Basic Mechanisms of Memory EncodingAcquisition of Information“Learning” ?MaintenanceRetaining informationRetrievalUsing informationHow do the processes of Encoding and Retrieval influence what is remembered?
42Levels of Processing Craik & Lockhart (1972) Formalized the notion of “depth” of processing and demonstrated how it affects memory.There are “depths” to which information can be processedShallow: encoding information in terms of its physical or sensory characteristicsDeep: encoding information in terms of meaningLevels (for words)StructuralIs it all caps?ShallowPhoneticDoes it rhyme with _?SemanticIs it an animal?Deep
43Proportion correctly recognized Levels of Processing100Proportion correctly recognizedCAPS?Rhyme?Animal?
44Levels of ProcessingSuch results suggests that deeper levels of processing produce more permanent retention than shallow levels of processing.Distinctiveness and elaboration may be responsible for the effectiveness of deep levels of processingOther resultsIntention to learn does not change LOP pattern of results (Hyde & Jenkins, 1973)Generation effect (Slamecka and Graf, 1978)Self-reference task encourages especially deep levels of processing (Rogers, Kuiper, & Kirker 1977Problem: What is “deep” and what is “shallow?”Circular logicIf processing is deep then retention will be better.If retention was better, then processing must have been deeper.There is no precise way to measure ‘depth’
45Encoding-Specificity Principle Information is available to the extent to which retrieval cue matches encodingTulving and Thomson, (1973)
46Morris, Bransford, & Franks (1977) Had people make one of two judgments at presentationShallow: Rhyming (Does it rhyme with hat?)Deep: Semantic (Does it have a tail?)Two test conditionsRecognitionRhyming“Hat”“Did you see a word that rhymes with X?”Test Condition either matched or mismatched original encoding
48Morris, Bransford, & Franks LOP effect for standard test.But opposite for rhyming testDeep processing does not always enhance memory
49Transfer Appropriate Processing Memory performance depends on the extent to which processes used at the time of learning are the same as those used when memory is testedLOP approach assumed that semantic processing was always superior to non-semantic processingThe transfer appropriate processing approach demonstrates that a form of encoding which is “shallow” for one purpose might be “deep” for another.ConclusionMemory not just a function of depth of processingDepends also on the match between encoding processes and type of test
50Interaction of Encoding and Retrieval Context CongruencyGodden & BaddeleyDivers memorized a list of wordsHalf learned the words on dry landHalf learned words underwaterTested either on dry land or underwater
51Recap LEVELS OF PROCESSING emphasizes operations at encoding semantic/elaborative processing better for LTMENCODING SPECIFICITYemphasizes that information about retrieval cue must be encoded at study for cue to be effectiveTRANSFER APPROPRIATE PROCESSINGmemory best when processes at test match processes used at study*For another view, see Nairne, 2002
52Different Methods of Retrieval What is your name?AutomaticWhat is the Capital of Australia?Generate & recognizeWhat are you doing next Tuesday at 1200?Schema + SearchWhat is the layout of your house?SpatialIs “FLORB” a word?Direct accessWhat was Beethoven’s telephone number?General knowledge search
53Basic Mechanisms General Principles of Memory Strength Congruity BackgroundContextualCongruityBetween encoding and retrievalOrganizationDistinctivenessSegregate item in memorySpacingMassed vs. DistributedRecency and Primacy
54Spacing Old rule: Spacing learning enhances recall Bahrick family and foreign language learning
55Spacing Why does it work? Varying encodings may lead to more associationsReminds of earlier presentation, so may reinforce earlier learning (perhaps increasing baseline activation)
56Recency and Primacy Demonstrated in the serial-position curve Learn a list of items in order…..and reproduce the list in orderPosition in ListProportion Recalled100Beg.Mid.End
57Recency and Primacy Primacy Recency Memory advantage for items initially encountered.Rehearsal?Distinctiveness?RecencyMemory advantage for items recently encountered.Working memory?
58Retrieval Many different theories about how retrieval takes place. Information Processing TheoriesModal Model, LOP, TAPAssociative TheoriesACT-R, TODAMSearch ModelsSAM, REMTrace TheoriesPerturbation ModelConnectionist ModelsPDP, EPICBiological-Based TheoriesHERA, CARADiffer…What and how information is retrieved.Memory traceReconstructionShare…Emphasis on information available at retrievalCuesContextual informationSomething guides retrievalMemory as a Decision