HUMAN MEMORYIt is good to have an end to journey towards; but it is the journey that matters, in the end.Ursula K. Le Gui1MEMORYProcess by which information is:AcquiredEncodingStored in the brainStorageLater retrievedRetrievalEventually (possibly) forgotten2INFORMATION-PROCESSING MODEL OF MEMORYComputer as a model for our memoryThree types of memorySensory memoryShort-term memory (STM)Long-term memory (LTM)Can hold vast quantities of information for many years3INFORMATION-PROCESSING MODEL OF MEMORYShort-termmemoryStimulusSensorymemoryLong-termmemoryAttentionEncodingRetrievalForgettingForgettingForgetting4SENSORY MEMORYStores all the stimuli that register on the sensesLasts up to three secondsTwo typesIconic memoryVisualUsually lasts about 0.3 secondsSperlings tests (1960s)Echoic memory (well come back to this)Sensory InputSensory Memory5SPERLINGS EXPERIMENTPresented matrix of letters for 1/20 secondsReport as many letters as possibleSubjects recalled only half of the lettersWas this because subjects didnt have enough time to view entire matrix? NoHow did Sperling know this?6SPERLINGS ICONIC MEMORY EXPERIMENT7SPERLINGS ICONIC MEMORY EXPERIMENT8Sperlings Iconic Memory Experiment9SPERLINGS ICONIC MEMORY EXPERIMENT10SPERLINGS EXPERIMENTSounded low, medium or high tone immediately after matrix disappearedTone signaled 1 row to reportRecall was almost perfectMemory for images fades after 1/3 seconds or so, making report of entire display hard to doHigh MediumLow11SENSORY MEMORYEchoic memorySensory memory for auditory input that lasts only 2 to 3 secondsWhy do we need sensory memory?12SHORT-TERM MEMORYFunctionConscious processing of informationAttention is the keyLimits what info comes under the spotlight of short-term memory at any given timeAKA working memory Working orShort-termMemorySensory InputSensory MemoryAttention13Memorize the following list of numbers:1 8 1 2 1 9 4 1 1 7 7 6 1 4 9 2 2 0 0 114Write down the numbers in order.15Now, try again1812 1941 1776 1492 200116SHORT-TERM MEMORYLimited capacityCan hold 7 2 items for about 20 secondsMaintenance rehearsalThe use of repetition to keep info in short-term memoryCHUNKMeaningful unit of informationWithout rehearsal, we remember 4 2 chunksWith rehearsal, we remember 7 2 chunksEricsson & Chase (1982)8931944349250215784166850612094888856877273141861054629748012949749659228017LONG-TERM MEMORYOnce information passes from sensory to short-term memory, it can be encoded into long-term memory Working orShort-termMemorySensory InputSensory MemoryAttentionLong-termmemoryRetrievalEncoding18LONG-TERM MEMORY - ENCODINGElaborative rehearsalA technique for transferring information into long-term memory by thinking about it in a deeper wayLevels of processingSemantic is more effective than visual or acoustic processingCraik & Tulving (1975)Self-referent effectBy viewing new info as relevant to the self, we consider that info more fully and are better able to recall it19LONG-TERM MEMORYProcedural (Implicit)Memories of behaviors, skills, etc.Demonstrated through behaviorDeclarative (Explicit)Memories of factsEpisodic personal experiences tied to places & timeSemantic general knowledgeSemantic network20SEMANTIC NETWORKSRedFireCherryRosesFire EngineApplesHouseGreenFlowersDaisiesYellowOrangeTruckBusAmbulanceSunriseSunsetsClouds21RETRIEVALRetrievalProcess that controls flow of information from long-term to working memory storeExplicit memoryThe types of memory elicited through the conscious retrieval of recollections in response to direct questionsImplicit memoryA nonconscious recollection of a prior experience that is revealed indirectly, by its effects on performance22RETRIEVAL EXPLICIT MEMORYFree-recall testA type of explicit memory task in which a person must reproduce information without the benefit of external cuesRecognition taskA form of explicit memory retrieval in which items are presented to a person who must determine if they were previously encounteredRetrieval failureTip-of-the-tongue (Brown & McNeill)23RETRIEVAL EXPLICIT MEMORYContext-Dependent MemoryWe are more successful at retrieving memories if we are in the same environment in which we stored themState-Dependent MemoryWe are more successful at retrieving memories if we are in the same mood as when we stored them24RETRIEVAL IMPLICIT MEMORYShowing knowledge of something without recognizing that we know itResearch with amnesicsDj vuThe illusion that a new situation is familiarEyewitness testimonyEyewitness transferenceUnintentional plagiarism25FORGETTINGIf we remembered everything, we should on most occasions be as ill off as if we remembered nothing.William JamesLack of encodingOften, we dont even encode the features necessary to remember an object/eventDecayMemory traces erode with the passage of timeNo longer a valid theory of forgettingJenkins & Dallenbach (1924)2627INTERFERENCE THEORYForgetting is a result of some memories interfering with othersProactive interferenceOld memories interfere with ability to remember new memoriesRetroactive interferenceNew memories interfere with ability to remember old memoriesInterference is stronger when material is similar28FORGETTINGRepressionThere are times when we are unable to remember painful past eventsWhile there is no laboratory evidence for this, case studies suggest that memories can be repressed for a number of years andrecovered in therapy29MEMORY CONSTRUCTIONSchema theoryPreconceptions about persons, objects, or events that bias the way new information is interpreted and recalledMisinformation effectThe tendency to incorporate false postevent information into ones memory of the event itselfIllusory memoriesPeople sometimes create memories that are completely false30IMPROVING MEMORYPractice timeDistribute your studying over timeDepth of processingSpend quality time studyingVerbal mnemonicsUse rhyming or acronyms to reduce the amount of info to be stored31IMPROVING MEMORYMethod of lociItems to be recalled are mentally placed in familiar locationsInterferenceStudy right before sleeping & review all the material right before the examAllocate an uninterrupted chunk of time to one courseContext reinstatementTry to study in the same environment & mood in which you will be taking the exam32