2Memory Studying Memory Building Memories An Information-Processing ModelTwo Memory TracksBuilding MemoriesEncoding: Getting Information InStorage: Retaining InformationRetrieval: Getting Information Out
4Memory Memory Construction Improving Memory Misinformation and Imagination EffectsSource AmnesiaChildren’s Eyewitness RecallRepressed or Constructed Memories of Abuse?Improving Memory
5Memory is the persistence of learning over time through the encoding, storage and retrieval of information
6Building a Memory To remember any information or experience requires: Encoding: getting information into our brainStorage: retaining the encoded informationRetrieval: getting the information back out of memory storage
7An Information-Processing Model A model of memory based on a computer (Atkinson & Shiffrin, 1968)Experience is first recorded, for just a moment, as a sensory memoryInformation is processed into short-term memory, encoded through rehearsalHolds a few items brieflyInformation moves to long-term memory for later retrieval
8Updates to the I-P Model Some memories are formed through unconscious processing, without our awarenessWorking memory: a view of short-term memory that stresses conscious, active processesWorking memory is not just a storage shelf, but an active desktop for linking new and old information
9Two-Track Processing: Automatic vs. Effortful We automatically process vast amounts of everyday informationWe remember new and important information through effortful processing
10Automatic Processing We automatically process information about Space “The definition was at the top of the right page”Time“I went to the store before lunch”Frequency“This is the third time I’ve seen her today!”
11Effortful Processing Requires close attention and effort Memory can be improved through rehearsal, the conscious repetition of informationRehearsal was the subject of one of many studies of memory by Hermann Ebbinghaus
12Ebbinghaus’s Experiment Studied his own learning and forgettingUsed lists of nonsense syllablesJIH, BAZ, FUB, YOX, SUJ, DAX, VUM, etc.Tested his memory for the list every day.The more he practiced out loud on day 1, the less time needed to relearn it on day 2
13Effortful ProcessingSpacing effect: we remember better if study or practice is spread over timeCramming is less effective!Testing effect: repeated quizzing of previously studied material also helps
14Serial PositionSerial position effect: We remember the first and last items in a list best
15Facts vs. SkillsH.M. and others with certain traumatic brain injuries cannot form new explicit memoriesCannot learn new factsHowever, they can learn new skills
16Two-Track MemoryImplicit memory: retaining skills or conditioning, often without conscious awarenessExplicit memory: memories of facts and personal events that can be consciously retrieved
18Sleep and Memory Sleep supports memory consolidation During sleep, the hippocampus and cortex display rhythmic patterns of activity, as if communicating with each otherThe brain may be “replaying” the day’s experiences as it transfers them to the cortex for long-term storage
19Building Memories Encoding: Getting Information In Storage: Retaining InformationRetrieval: Getting Information Out
20Encoding Meaning We may encode meaning rather than raw information When asked to recall text, we often report the meaning, or gist, rather than the raw textIt can be difficult to remember things without a meaningful context
21Encoding ImagesWe can more easily remember things we can process visually as well as meaningfullyOld Bailey (court in London)--Glen BaileyMemorable sentences often evoke powerful imagery, or mental picturesHOMES—the great lakesOn Old Olympus' Towering Top, A Finn And German Viewed Some Hops—the cranial nerves:Olfactory, Optic, Oculomotor, Trochlear, Trigeminal, Abducens, Facial, Vestibulocochlear, Glossopharyngeal, Vagus, Spinal Accessory, Hypoglossal
22Sensory MemoryStorage is extremely short, especially for visual sensory memoryStudy: Sperling (1960) flashed nine letters for 1/20th of a second.Sensory memory made the letters momentarily available for encoding.
23Short-Term Memory: Duration Study: Peterson (1959) presented 3-letter strings and prevented rehearsalResult: letters 50% gone at 3 seconds, 90% gone at 12 seconds.Conclusion—without rehearsal—doesn’t last long
24Storage Capacities Short-term memory capacity is limited The Magical Number Seven, plus or minus two (George Miller, 1956)7 digits or 7 chunks of informationLong-term memory seems to have no limit and can endure for a lifetime
25How Does the Brain Store Memory? Memory is not stored like books in a library, in neat, precise locations.Rather, different aspects of a memory are assigned to various groups of neurons.Thus, to understand how memory works, we must study the brain
26Synaptic ChangesSynapses are the sites where the signal from one neuron is received by anotherExperience modifies the brain’s neural network: increased activity in a pathway strengthens connections between the neurons involved
27Synaptic ChangesKandel and Schwartz (1982) classically conditioned sea slugs to withdraw their tail when squirted with water (with electric shock).As the slug learned, serotonin was released into certain synapses. These synapses then become more sensitive and able to transmit signals more effectively.
28Synaptic ChangesLong-Term Potentiation (LTP): An increase in a synapse’s firing potential. A neural basis for learning and memory
29Stress-Related Memories Excitement of stress can enhance memories.Stress hormones more available glucose to fuel brain activity signals brain “something important has happened”Do you suppose that is why the pilot at Nellis AFB had found it much easier to count air craft on the ground when he made high speed-low altitude runs over airfieldsin hostile North Vietnamthan in peaceful England?
30Flashbulb MemoriesEmotion-triggered hormone changes help explain flashbulb memories, unusually clear memories of an emotionally significant moment or eventDo you remember exactly where they were on September 11, 2001?
31Retrieval: Getting Information Out Evidence that something has been remembered:The item can be recalled, on an essay examThe item can be recognized, as on a multiple-choice testRecognition memory is quick and vastRelearning the item may be easier than it was the first time
32Retrieval CuesMemories are linked together in the brain, in a storage web of associations.These associations can serve as retrieval cues, any stimuli (events, feelings, places, etc.) linked to a specific memoryWe haven’t been at the GOP (Garden of Paradise) but thinking back—Al was at the cash register on that occasion.We’ve not been to Skewer’s for a couple years-but Hani showed us to our table.The more retrieval cues you’ve encoded, the better chance of finding a path to retrieve the memory
33Context EffectsReturning to the context where you experienced something can prime your memory of itGodden and Baddeley (1975) had scuba divers learn lists of words on land or underwater, and then attempt to recall them in the same or different context
34Context EffectsSometimes being in a similar context to one previously experienced can trigger the eerie feeling of déjà vu (I’ve seen this before)This can happen when the current situation is loaded with retrieval cues that remind us of earlier, similar experiencesWhere was I went I originally learned this particular materials—in class or sitting at home
35Moods and MemoriesMood-congruent memory: we more easily recall experiences that are consistent with the current (good or bad) moodIf we are in a good mood, we tend to remember good experiencesTeen ratings of their parents are tightly linked to the teen’s current moodIf your kid rates you as a parent after waking up grouchy, what kind of rating will he make?
36Forgetting Jill Price is unable to forget anything. Why might this be a problem?
37Seven Sins of Memory (Daniel Schacter, 1999) “Sins” of forgetting and retrieval, problems with the way memory worksAbsent-mindedness – inattention to detail leads to encoding failureTransience – memory loss as unused information fadesBlocking – inability to access stored information
38Seven Sins of Memory (Daniel Schacter, 1999) Sins of distortionMisattribution – confusing the source of informationSuggestibility – e.g., asking a leading question influences answer and subsequent memoryBias – belief-colored recollections. Current feelings may alter a memory.Sin of intrusionPersistence – unwanted memories (e.g., PTSD)
39Encoding FailureWe cannot remember what we have not encoded
40Storage Decay Forgetting is initially rapid, and then levels off People who had studied Spanish in high school but not after were tested on vocabulary recallOne explanation may be a gradual fading of the memory trace, the physical changes in the brain as a memory forms
41Retrieval FailureWe can sometimes fail to retrieve a memory because we don’t have enough information to access the pathway to it
42InterferenceInterference: the blocking of recall as old or new learning disrupts the recall of other memoriesLearning new passwords may interfere with remembering older onesLearning an hour before sleep can be good because of less interference (but still need rehearsal)
43ForgettingForgetting, the loss of information in between sensation and retrieval, can occur at any stagesSensory memoryShort term memoryLong term memory
44Repressed MemoriesFreud argued that we repress, painful or unacceptable memories to minimize anxietyHe argued that these repressed memories linger, and can be retrieved by some later cue or therapyToday, many memory researchers think repression rarely, if ever, occurs
45Memory ConstructionEvery time we “replay” a memory, we replace the original with a slightly modified versionWhat implications does this have for everyday life?My wife and I can have very different memories of an event that we’ve both experienceAnd that divergence may grow over time
46MisinformationMisinformation effect: a memory that has been corrupted by misleading informationLoftus and Palmer (1974) has subjects watch a film of a traffic accident.“How fast were the cars going when they smashed into each other?”or“How fast were the cars going when they hit each other?”
47MisinformationPeople who were asked “smashed” version reported higher speedsA week later, they were more likely to (falsely) recall seeing broken glass
48False Memory and Eyewitness Testimony Even hearing a vivid retelling of an event can implant false memoriesSample of 200 convicts later proven innocent by DNA testing79% misjudged based on faulty eyewitness identificationLeading questions (“Did you hear loud noises”) can lead to false memories
49Imagination and Memories Even imagining fake actions and events can create false memoriesCollege students were asked to imaging specific childhood events (like breaking a window with their hand). 25% later recalled the event as actually having happened.Possible cause: visualizing something and actually perceiving it activate similar brain areas
50Source AmnesiaSource amnesia: faulty memory for how, when, or where information was learned or imaginedSometimes experienced by songwriters and authors, who may unintentionally plagiarize something
51Children’s Eyewitness Recall How can jurors decide cases in which children’s memories of sexual abuse are the only evidence?When 3 year-olds were asked to show on a doll where a pediatrician had touched them, 55% pointed to the genitals or anus, even though the doctor had not touched them thereUse non-leading questions soon after the event, in language the child can understand
52Repressed or Constructed Memories of Abuse Two tragedies concerning adult recollections of childhood abuse:When people don’t believe abuse survivors who share their secretWhen truly innocent people are falsely accusedWhat about clinicians who help people “recover” memories of abuse?
53Guidelines for Thinking about Recovered Memories of Sexual Abuse Sexual abuse happensInjustice happensForgetting happensRecovered memories are commonplaceMemories of things happening before age 3 are unreliable (Infantile amnesia)Memories “recovered” under hypnosis of under the influence of drugs are especially unreliableMemories, whether real or false, can be emotionally upsetting
54Horror Carves a MemoryThe most common response to a traumatic experience is not to banish the experience into the unconscious.Rather, such experiences are typically etched on the mind as vivid, persistent, haunting memories.
55Tips for Improving Memory Study repeatedlySpace study sessions apartSpend more time rehearsing or actively thinking about the materialMake the material personally meaningfulActivate retrieval cuesMinimize interferenceSleep moreTest your knowledge, both to rehearse it and to find out what you don’t know