Memory Rozalia Ivady BME – Cognitive Science Department ImpLab Scientific Society Psychology Class, McDaniels College, 29th October 2007 Memory – an outline Multiple stores Retention curves – serial position data Memory dysfunctions Sensory memory Short term memory Long term memory Three processes Forgetting Explicit and implicit memory Constructive memory Psychology and the law But before anything else Provo is a picturesque region of France. Corman was a pretender to the throne of Provo. He was tired of waiting. He thought arsenic might work. Try to remember these! Look at these pictures Now look carefully at these pictures. You will need to recall them later. Memory – an outline Multiple stores Retention curves – serial position data Memory dysfunctions Iconic memory Short term memory Long term memory Three processes Explicit and implicit memory Constructive memory Psychology and the law Try to recall as many items as you can! Cat Chair Apple Screw Banana Pigeon Hammer Orange Toothpick Knife Parrot Bed Table Dog Blackberry Fork Fly Rat Multiple stores or MLP? Multiple stores or MLP? Primacy effect Recency effect The Atkinson-Shiffrin Model Maintenance Rehearsal Sensory Input Sensory Memory Attention Encoding Working or Long-term Short-term memory Memory Retrieval Memory dysfunctions - amnesia Famous Anterograde Amnesiac: HM Severe epilepsy, treated with surgery to bilaterally remove medial temporal lobes, including hippocampus Operation 9/1953, 27 years old Anterograde Amnesia Inability to acquire new information “memento” Does not affect short-term memory and general knowledge from the past But, it is difficult to learn new facts Affects memory regardless of modality (visual, auditory, tactile, etc). Spares skilled performance Hyper-specific memory for those skills that are learned after onset – learning is expressed only in context in which it was encoded Amnesia Types of amnesia Anterograde Retrograde Memory – an outline Multiple stores Retention curves – serial position data Memory dysfunctions Sensory memory Short term memory Long term memory Three processes Explicit and implicit memory Constructive memory Psychology and the law There is more than we can tell… Eidetic pictures of children How many stripes did you see on the cat? Sensory Memory Store Function - holds information Sensory Input Sensory Memory long enough to be processed for basic physical characteristics Capacity - large can hold many items at once Duration - very brief retention of images .3 sec for visual info 2 sec for auditory info Sensory Memory Store Divided into two subtypes: Sensory Input Sensory Memory iconic memory - visual information echoic memory auditory information Visual or iconic memory was discovered by Sperling in 1960 Sperling’s Experiment Presented matrix of letters for 1/20 seconds Report as many letters as possible Subjects recall only half of the letters Was this because subjects didn’t have enough time to view entire matrix? No How did Sperling know this? Sperling’s Experiment Sperling showed people can see and recall ALL the letters momentarily Sounded low, medium or high tone immediately after matrix disappeared tone signaled 1 row to report recall was almost perfect Memory for image fades after 1/3 seconds or so, making report of entire display hard to do High Medium Low Sperling’s Iconic Memory Experiment Sperling’s Iconic Memory Experiment Sperling’s Iconic Memory Experiment Sperling’s Iconic Memory Experiment Sperling’s Iconic Memory Experiment G A V M K U X L S F Q J O N U A N Z What Letters Do You See? DiLollo ….. What Letters Do You See? ….. ….. What Letters Do You See? ….. Sensory Memory Store Sensory memory forms Sensory Input Sensory Memory automatically, without attention or interpretation Attention is needed to transfer information to working memory Memory – an outline Multiple stores Retention curves – serial position data Memory dysfunctions Sensory memory Short term memory Long term memory Three processes Explicit and implicit memory Constructive memory Psychology and the law Working Memory Store Sensory Input Sensory Memory Attention Working or Short-term Memory The Atkinson-Shiffrin Model Maintenance Rehearsal Sensory Input Sensory Memory Attention Encoding Working or Long-term Short-term memory Memory Retrieval Working Memory Store Function - conscious processing of information where information is actively worked on Capacity - limited (holds 7 +/- 2 items) Duration - brief storage (about 30 seconds) Code - often based on sound or speech even with visual inputs Sensory Input Attention Sensory Memory Working or Short-term Memory Working Memory Store What happens if you need to keep information in working memory longer than 30 seconds? To demonstrate, memorize the following phone number (presented one digit at a time)... 8 5 7 91 6 3 Working Memory Store 857-9163 What is the number? The number lasted in your working memory longer than 30 seconds So, how were you able to remember the number? Maintenance Rehearsal Mental or verbal repetition of information Allows information to remain in working memory longer than the usual 30 seconds Maintenance rehearsal Sensory Input Sensory Memory Attention Working or Short-term Memory Maintenance Rehearsal What happens if you can’t use maintenance rehearsal? Memory decays quickly To demonstrate, again memorize a phone number (presented one digit at a time) BUT, have to count backwards from 1,000 by sevens (i.e., 1014, 1007, 1000 … etc.) 6 2 8 50 9 4 Working Memory Store 628-5094 What is the number? Without rehearsal, memory fades Peterson’s STM Task Test of memory for 3- letter nonsense syllables Participants count backwards for a few seconds, then recall Without rehearsal, memory fades Working Memory Model Baddeley (1992) 3 interacting components Visuospatial Sketch Pad Central Executive Phonological Loop Working Memory Model Visuospatial sketch pad - holds visual and spatial info Phonological loop - holds verbal information Central executive - coordinates all activities of working memory; brings new information into working memory from sensory and long-term memory Visuospatial Sketch pad Central Executive Phonological Loop Long-Term Memory Store Once information passes from sensory to working memory, it can be encoded into long-term memory Maintenance Rehearsal Sensory Input Sensory Memory Attention Encoding Working or Long-term Short-term memory Memory Retrieval Long-Term Memory Store Function - organizes and stores information more passive form of storage than working memory Unlimited capacity Duration - thought by some to be permanent Maintenance Rehearsal Sensory Input Attention Sensory Memory Encoding Working or Long-term Short-term memory Memory Retrieval Review of Long-Term Memory Organizes and stores information Capacity unlimited Thought by some to be permanent Encoding transfers info from STM to LTM Maintenance Rehearsal Sensory Input Attention Sensory Memory Encoding Working or Long-term Short-term memory Memory Retrieval Summary Modal model of memory three memory stores (sensory, working and long-term memory) Three processes and sins of memory Encoding - process that controls movement from working to long-term memory store Storage Retrieval - process that controls flow of information from long-term to working memory store Forgetting and the fight against it Elaboration Chunking Thories of forgetting Problems in encoding Problems of retention Problems of retrieval – interference ,inhibition Elaboration Focus on meaning of information to encode it into LTM don’t simply repeat items over and over tie item to other info in memory also called elaborative rehearsal Ways to Use Elaboration Actively question new information Think about its implications Relate information to things you already know Generate own examples of concepts Don’t highlight passage as you read focus on the ideas in the text Which Level is More Effective? Elaboration leads to better recall than shallow processing Type of Processing Deep 0 Shallow -Acoustic Shallow - Visual 10 20 30 40 50 60 70 80 Percent of words recalled 90 100 More Evidence for Elaboration Positive correlation between grades and use of elaboration in 5th grade students In an experiment, college students assigned to use elaboration received higher grades than students not taught elaboration Chunking Grouping small bits of information into larger units of information expands working memory load Which is easier to remember? 4 8 3 7 9 2 5 1 6 483 792 516 Visualization Key word method Method of loci Forgetting Theories Encoding failure Role of time Interference theories Forgetting as Encoding Failure Information never encoded into LTM X Encoding Failure Demonstrations What letters accompany the number 5 on your telephone? Where is the number 0 on your calculator? According to this theory, objects seen frequently, but information is never encoded into LTM Forgetting as Retrieval Failure Not all forgetting is due to encoding failures Sometimes information IS encoded into LTM, but we can’t retrieve it X Role of Time : Decay Theory Memories fade away or decay gradually if unused Time plays critical role Ability to retrieve info declines with time after original encoding Problem: Many things change with time. Something else may change and actually cause forgetting: Interference Interference Theories “Memories interfering with memories” Forgetting NOT caused by mere passage of time Caused by one memory competing with or replacing another memory Two types of interference Two Types of Interference Types of interference Retroactive Interference Proactive Interference Retroactive Interference When a NEW memory interferes with remembering OLD information Example: When new phone number interferes with ability to remember old phone number Retroactive Interference Example: Learning a new language interferes with ability to remember old language Proactive Interference Opposite of retroactive interference When an OLD memory interferes with remembering NEW information Example: Memories of where you parked your car on campus the past week interferes with ability find car today Proactive Interference Example: Previously learned language interferes with ability to remember newly learned language Retrieval Cue Theories Retrieval cue - a clue, prompt or hint that can help memory retrieval Forgetting is the result of using improper retrieval cues Encoding Specificity Principle Learn word list generate ‘cue’ when see word (jam - jelly) at recall cues given as retrieval aid (jelly or traffic) Cues generated during learning (jelly) more effective during retrieval than new cues (traffic) Context-Dependent Memory Improved ability to remember if tested in the same environment as the initial learning environment better recall if tested in classroom where you initially learned info than if moved to a new classroom if learning room smells of chocolate or mothballs, people will recall more info if tested in room with the same smell compared to different smell or no smell at all Context-Dependent Effects Compare words learned underwater vs on land Words heard underwater are best recalled underwater Words heard on land are best recalled on land Context Dependent Effects Time of day is also important Learn at 3 pm Perform better at 3 pm Than 9 pm 12 12 12 9 3 6 9 3 6 9 3 6 State-Dependent Memory Recall improved if internal physiological or emotional state is the same during testing and initial encoding Context vs State dependent Context-dependent - external, environmental factors State-dependent - internal, physiological factors State-Dependent Effects Mood or emotions also a factor Bipolar depressives information learned in manic state, recall more if testing done during manic state information learned in depressed state, recall more if testing done during depressed state State Dependent Effects If drink during learning May recall better with drink Than without But not as well as sober all the way! Memory – an outline Multiple stores Retention curves – serial position data Memory dysfunctions Sensory memory Short term memory Long term memory Three processes Forgetting Explicit and implicit memory Constructive memory Psychology and the law Constructing memories Recall the sentences from the beginning of the lesson! Write them down. Memory Construction Recall not an exact replica of original events Recall a construction built and rebuilt from various sources Often fit memories into existing beliefs Remember those drawings? Can you draw them? Time can be even shorter The War of the Ghosts One night two young men from Egulacwent down to the river to hunt seals, and while they were there it became foggy and calm. Then they heard war-cries, and they thought: "Maybe this is a war-party". They escaped to the shore, and hid behind a log. Now canoes came up, and they heard the noise of paddles, and saw one canoe coming up to them. There were five men m the canoe, and they said: "What do you think? We wish to take you along. We are going up the river to make war on the people". One of the young men said: "I have no arrows". "Arrows are in the canoe", they said. "I will not go along. I might be killed. My relatives do not know where I have gone. But you", he said, turning to the other, "may go with them." So one of the young men went, but the other returned home. And the warriors went on up the river to a town on the other side of Kalama. The people came down to the water, and they began to fight, and manywere killed. But presently the young man heard one of the warriors say: "Quick, let us go home:that Indian has been hit". Now he thought: "Oh, they are ghosts". He did not feel sick, but they said he had been shot. So the canoes went back to Egulac, and the young man went ashore to his house, and made a fire. And he told everybody and said: " Behold I accompanied the ghosts, and we went to fight. Many of our fellows were killed, and many of those who attacked us were killed. They said I was hit, and I did not feel sick". He told it all, and then he became quiet. When the sun rose he fell down. Something black came out of his mouth. His face became contorted. The people jumped up and cried. He was dead. Recall the story 3 months later Some warriors went to wage way against the ghosts. They fought all day and one of their number was wounded. They returned home in the evening, bearing their sick comrade. As the day drew to a close, he became rapidly worse and the villagers came round him. At sunset he sighed: something black came out of his mouth. He was dead. Schema Theories Schema - mental representation of an object, scene or event example: schema of a countryside may include green grass, hills, farms, a barn, cows, etc. Scripts - type of schema mental organization of events in time example of a classroom script: come into class, sit down, talk to friends, bell rings, instructor begins to speak, take notes, bell rings again, leave class, etc. Schemas & scripts provide framework for new information Eyewitness Testimony Memory can be distorted as people try to fit new info into existing schemas Eyewitnesses usually see something complex just once then have to remember it Sometimes new information is distorted by fitting into an existing schema subsequent information (famous experiment by Loftus) Loftus Experiment Subjects shown video of an accident between two cars Some subjects asked: How fast were the cars going when they smashed into each other? Others asked: How fast were the cars going when they hit each other? Loftus’s Results Speed estimates depended on how the question was phrased Subjects memory for broken glass also depended on the phrasing of the speed question. But this was a false memory: there was no broken glass Memory – an outline Multiple stores Retention curves – serial position data Memory dysfunctions Sensory memory Short term memory Long term memory Three processes Forgetting Explicit and implicit memory Constructive memory Psychology and the law Long-term Memory Systems Long-term Memory Explicit Memory Episodic Memory Semantic Memory Implicit Memory Procedural Memory Classical Conditioning Priming Explicit Memory Also known as declarative or conscious memory Properties: memory consciously recalled or declared Can use to directly respond to a question Two subtypes of explicit memory Subtypes of Explicit Memory Explicit Memory Episodic Memory Semantic Memory Episodic Memory Memory tied to your own personal experiences Examples: what did you have for dinner? do you like to eat caramel apples? Why are these explicit memories? Because you can actively declare your answers to these questions Semantic Memory Memory not tied to personal events General facts and definitions about the world Examples: who was George Washington? what is a cloud? what is the climate at the north pole? These are explicit memories because you can describe what you know about them. Unlike episodic memories, your knowledge does NOT include your personal experience i.e., You may never have been to the north pole but do know about it. Implicit Memory Also known as nondeclarative memory Influences your thoughts or behavior, but does not enter consciousness Three subtypes Subtypes of Implicit Memory Implicit Memory Classical Conditioning Procedural Memory Priming Classical Conditioning Studied earlier Implicit because it is automatically retrieved Procedural Memory Memory that enables you to perform specific learned skills or habitual responses Examples: Riding a bike How to speak grammatically Tying your shoe laces Why are these procedural memories implicit? Can’t readily describe their contents try describing how to tie your shoes They are automatically retrieved when appropriate Priming Priming is influence of one memory on another priming is implicit because it does not depend on awareness and is automatic Here is a demonstration Priming Demonstration Unscramble the following words: O R E S ROSE L T E P A PETAL K T A L S STALK TSME STEM L O B S O M S BLOSSOM ELAF Priming Demonstration ELAF = LEAF Why not respond FLEA? Because flower parts were primed (flower power) Priming Activation of one or more existing memories by a stimulus Activation not a conscious decision BUT, can effect subsequent thoughts and actions Two types of priming Two Types of Priming Priming Conceptual Perceptual Conceptual Priming The semantic meaning of priming stimulus influences your encoding or retrieval Thought to involve activation of concepts stored in semantic memory Example: Flower power priming demonstration Does not depend on sense modality: pictures can conceptually prime sounds AS THE NEXT SLIDE SHOWS Priming across modalities Look at the picture . Then when the instructor says a word, write it down. Perceptual Priming Prime enhances ability to identify a test stimulus based on its physical features Does not work across sense modalities Perceptual Priming Can you identify the fragmented stimulus to the right? Perceptual Priming What if you were shown the following slide earlier in the lecture? Perceptual Priming Can you identify the fragmented stimulus to the right? Evidence for Separate Implicit/Explicit Systems Neurophysiological evidence Patient H.M. life-threatening seizures originating in temporal lobe surgically removed portions of temporal lobe Temporal Lobe Includes: hippocampus amygdala Patient H.M. Surgery was effective in reducing seizures BUT, had other side effects as well Can remember explicit memories acquired before the surgery e.g., old addresses, normal vocabulary Cannot form NEW explicit memories e.g., remembering the name of someone he met 30 minutes prior cannot name new world leaders or performers can recognize a picture of himself from before his surgery but not from after and doesn’t recognize himself in a mirror Patient H.M. H.M. has severe explicit / declarative memory disorder H.M. is almost normal on procedural or implicit memory tasks including priming, classical conditioning, and learning motor skills This shows that explicit memory depends upon the temporal lobes and implicit does not Patient H.M. Summary Temporal lobe damage led to deficits in explicit, but not implicit memory H.M. had both episodic and semantic memory deficits Damage to the hippocampus alone produces episodic, but not semantic memory deficits Why did H.M. show both types of explicit memory deficits? He had damage not only to hippocampus, but to other structures as well Memory – an outline Multiple stores Retention curves – serial position data Memory dysfunctions Sensory memory Short term memory Long term memory Three processes Forgetting Explicit and implicit memory Constructive memory Psychology and the law Thank you for your attention, that much on memory today….