6What Is Memory?Definition: learning that has persisted over time; The ability to retain knowledgeAdaptive AdvantageAllowed animals to use information from the past to respond quickly to immediate challenges
7Hermann Ebbinghaus Memorized series of nonsense syllables(TUV YOF GEK) More times he practiced the list on day 1, the fewer repetitions he required to relearn it on day 2Retention Curve
8Information Processing Model Memory system is often compared to that of a computerInformation has to be encoded (getting information to our brain)Then stored (retained)And finally retrieved (getting in out of the memory system)
9Three Stage Processing Model Proposed by Richard Atkinson and Richard ShiffrinSee pg 187RehearsalSensory InputForgettingForgetting
11Automatic v. Effortful Processing Automatic Processing: Unconscious encoding of incidental information such as space, time, and frequency, and of well-learned information, such as word meaningsSpace – we often encode the place on the page where material appearsTime – we unintentionally note the sequence of a day’s eventsFrequency – we effortlessly keep track of how many times things happen (I ran into you four times today!)Well-learned information – reading billboards, the writing on a truckEffortful Processing: Encoding that requires attention and conscious effortOften produces durable and accessible memories
12Effortful Processing: Rehearsal & Spacing Effect Rote Rehearsal: Repeating information over and overBoosts memorySpacing Effect: Distributed v. Massed RehearsalDistributed practice yields better long-term retention than is achieved through massed study/practiceRepeated quizzing also helps“Testing is a powerful means of improving learning, not just assessing it.” – Henry Roediger and Jeffrey Karpicke
13Rehearsal: Serial Position Effect Our tendency to recall best the last and first items in a listPrimacy Effect: Enhanced recall for items at the beginning of the listMore time to practiceRecency Effect: Enhanced recall for the last items on a listStill in working/short-term memoryPresidents, names, word lists, etc.
14What We Encode Visual: Encoding of picture images (imagery) Acoustic: Encoding of sound (the sound of words)Semantic: Encoding of meaning (meaning of words)Which yields the best memory of verbal information?Fergus Craik and Endel TulvingFlashed a word at peopleThen asked a question that required participants to process the word visually, acoustically, or semanticallyIs the word in capital letters?Does the word rhyme with train?Would the word fit into this sentence? The girl put the ______on the table.
16Organizing Information for Encoding Chunking: Organizing items into familiar, manageable units; often occurs automaticallyFBIIRSCIAEPAFBI IRS CIA EPAHierarchies: Composed of a few broad concept divided and subdivided into narrower concepts
17Encoding: Mnemonic Device A memory trick or technique for remembering specific facts“Every good boy does fine” to remember the notes on the lines of the scale“People say you could have odd lots of good years” as a way to remember how to spell “psychology”
18Loci Method: A person associates items to be remembered with places Mnemonic DevicesLoci Method: A person associates items to be remembered with placesPeg-Word: A person associates items to remember with a list of peg words already memorizedGoal is to visualize the items to remember with the items on the pegs
21Sensory Memory/Sensory Registers First stage of storage that holds large amounts of incoming data for very brief amounts of timeIconic Memory: Momentary sensory memory of visual stimuliA photographic or picture-image memory lasting no more than a few tenths of a secondEchoic Memory: Momentary sensory memory of auditory stimuliIf attention is elsewhere, sounds and words can still be recalled within 3 or 4 seconds
22Sensory Memory Experiment Sperling (1960)R G T F M Q L Z S“Recall”R T M Z(44% recall)50 ms (1/20 second)The exposure time for the stimulus is so smallthat items cannot be rehearsed.
23Partial Report S X T J R S P K Y “Recall” J R S (100% recall) Low Tone Medium ToneHigh Tone“Recall”J R S(100% recall)50 ms (1/20 second)Sperling (1960) argued that sensory memory capacity was larger than what was originally thought.
24Time Delay A D I N L V O G H “Recall” N _ _ (33% recall) Low Tone Medium ToneHigh Tone“Recall”N _ _(33% recall)TimeDelay50 ms (1/20 second)
25The duration of sensory memory varies for the different senses. Sensory MemoriesThe duration of sensory memory varies for the different senses.Iconic0.5 sec. longEchoic3-4 sec. longHepatic< 1 sec. long
26Working Memory (Short-Term) A tiny amount of information from your sensory registers will move to short term memoryConscious, activated memory which holds information briefly before it is stored or forgottenStays in as long as you can rehearse itSlightly better for what we hear than what we seeSmall capacityCan hold the “magic number 7 plus or minus 2” – George MillerCan increase it by chunkingAlso called working memoryActively manipulating information
27From Short Term to Long Term Moves to long term as a result of rehearsalElaborative Rehearsal: linking new material to things you already know
28Long Term Memory Capacity is limitless Estimates on capacity range from 1000 billion to 1,000,000 billion bits of information (Landauer, 1986)
29Types of Long term Memories Explicit (Declarative): Memories for information we can readily express in words and that we are aware of having; Can be intentionally retrieved from memorySemantic: Facts and concepts not liked to a particular time; Like a dictionary or encyclopediaEpisodic: Personally experienced eventsProcessed by hippocampus (active during deep sleep), not stored hereImplicit (Nondeclarative): Memories for information that we cannot readily express in words and may not be aware of havingProcedural: motor skills and habitsEmotional Memories: learned emotional responses to various stimuli (usually through classical conditioning)Processed by the cerebellumFlashbulb memories
31Warning Memories are not stored in one “spot” in the brain Working memory is processed in the prefrontal cortex and temporal lobeLong-term semantic memories are located in the frontal and temporal lobesEpisodic: frontal and temporal
32Neural Basis for memory Long-Term Potentiation (LTP)A long-lasting change in the structure or function of a synapse that increases the efficiency of neural transmission and is thought to be related to how information is stored by neuronsAn increase in neurotransmitter release or receptors on the receiving neuron indicates strengthening of synapses
33Stress and memories In stressful situations Emotion-triggered stress hormones make more glucose energy available for brain activityBoost in amygdala activityResult: Arousal can sear certain events into the brainEpinephrine and cortisol can affect long-term retention of negative memoriesSudden stress hormones can block older memories
34RetrievalRecall v. Recognition: We remember more than we recall
35Mind reconstructs a memory out of the stored bits During retrieval, information flows from long-term memory back to working memoryMind reconstructs a memory out of the stored bitsRetrieved information is blended with the new content currently present in the working memoryProne to changeFuture retrievals will bring up the modified file!
36Cues: Stimulus that helps you access target information Recognition!Most effective cues are those we generate ourselvesElaborative rehearsalThe more retrieval cues, the more likely you are to rememberPriming: The activation, often unconsciously, of particular associations in memory
37Context/Mood Congruent Memory Context Congruent Memory: Enhanced ability to retrieve information when you are in an environment similar to the one in which you encoded the informationMore similar to your retrieval circumstances are to your encoding circumstances, the more likely you are to remember the informationRetracing your footstepsRevisiting the scene of a crimeMood Congruent Memory: The tendency to recall experiences that are consistent with one’s current good or bad mood
39Why Do we Forget? Daniel Schacter Three Sins of Forgetting Absent-mindedness: inattention to details leads to encoding failureTransience: storage decay over timeBlocking: inaccessibility of stored informationThree Sins of DistortionMisattribution: confusing the source of informationSuggestibility: the lingering effects of misinformationBias: belief-colored recollectionsOne Sin of Intrusion:Persistence: unwanted memories
40Most of what we sense we never notice Slower encoding with age Encoding FailureMost of what we sense we never noticeIf you don’t encode it, you can’t retrieve itSlower encoding with age
43Storage Decay Hermann Ebbinghaus’ “Forgetting Curve” We forget a lot right away, but then it levels off!Result: Some memories do “decay”Explanation?Fading of the memory traces in our brains?
44Retrieval FailureForgetting is often a result of not being able to get out the memories we have storedWhy?Proactive Interference: Something you learned earlier disrupts your recall of something you learn laterForward-actingRetroactive Interference: Occurs when new information makes it harder to recall something you learned earlierBackward-actingInformation that is presented in the hour before sleep is protected from retroactive interferenceBut not in the few minutes before sleep!
45Motivated forgetting We unknowingly revise our memories People who were told the benefit of tooth-brushing recalled having frequently more brushed their teeth in the preceding two weeks then people who were not told the benefit of tooth-brushingMemory is often self-servingSigmund Freud and MemoryWe repress (banish from the conscious) painful memories to protect our self-concept and to minimize anxiety“Submerged” memory will linger and could be retrieved by some later cue or during therapyMany psychologists think repression is rareWe might actually be more likely to remember emotional memories
46Memory constructionWe infer our past from stored information plus what we later imagined, expected, saw, or heardElizabeth LoftusMisinformation Effect: After exposure to subtle misinformation, many people misrememberWe alter and save the new fileOne experiment showed people digitally altered photos depicting themselves (from childhood) taking a hot air balloon ride three times over two weeks, half of the participants “remembered” the experienceIt is then hard for us to discriminate between these altered and real memoriesSource Amnesia (misattribution): attributing to the wrong source an event we have experienced, heard about, read about, or imaginedRumors!
47Children and Eyewitness Recall Children’s memories are extremely susceptible to suggestibilityExperimentsResearchers asked 3-year-olds to show on anatomically correct dolls where a pediatrician had touched them; 55% of children who had not received genital examinations pointed there.Preschoolers overheard a false comment that a magician’s rabbit had gotten loose in their classroom. Later, when suggestively questioned , 78% recalled actually seeing the rabbit.Children chose cards from a deck of possible happenings and an adult read the card followed by, “Think real hard, and tell me if this ever happened to you. Can you remember going to the hospital with a mousetrap on your finger?” After 10 weekly interviews, with the same adults repeatedly asking children to think about several real and fictitious events, a new adult asked the same question. 58% produced false, often vivid, stories regarding one or more events they had never experienced.
48Suggestions for children’s testimony Use a neutral personDo not ask leading questionsKeep children from involved adults
49Recovering repressed memories Can clinicians help their patients “recover” memories of childhood abuse?How can we interpret therapists who use “memory work” techniques like guided imagery, hypnosis, and dream analysis?
50Agreed upon facts Regarding Repressed memories 1. Sexual abuse happens2. Injustice happens3. Forgetting happens4. Recovered memories are commonplaceDo our minds forcibly repress painful experiences?5. Memories of things happening before age 3 are unreliable6. Memories “recovered” under hypnosis or the influence of drugs are especially unreliable7. Memories, whether real or false, can be emotionally upsetting
51Types of AmnesiaAnterograde Amnesia: Cannot recall events that happen after the onset of the amnesiaDamage to hippocampusRetrograde Amnesia: Cannot recall events before the amnesia set inDisease, brain injuryInfantile Amnesia: Most people cannot remember events prior to the age of 3Immaturity in parts of the brain