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Chapter 9 – Memory – ‘15 The Phenomenon of Memory – memory definition, Shereshevkii, us; the nature of our memory – flashbulb memories Information Processing – encoding, storage, retrieval; us vs. computers -3 stage processing: sensory memory, short-term / working memory, long-term memory Getting It In: How We Encode: Automatic processing versus effortful processing; rehearsal – Hermann Ebbinghaus overlearning, next-in-line effect, distributed learning / the spacing effect, serial position effect What We Encode: Organizing -visual, acoustic and semantic encoding; self-reference effect, rosy retrospective, imagery – mnemonic devices: method of loci, peg-word, chunking, acronyms, hierarchies What We Retain: Storage Sensory memory: Sperling; iconic, echoic memory Short-term / working memory – length / decay, Miller: “magic 7+/- 2”; Long-term memory – capacity, Rajan Mahadevan… -Storage: AKA memory trace -WHERE? Wilder Penfield, Karl Lashley; -WHAT? Synaptic changes, serotonin, CREB, glutamate, Long-Term Potentiation (LPT); -stress and memory: long versus short-term, amnesia -explicit memory: AKA declarative (includes SEMANTIC and EPISODIC), route -- hippocampus -implicit memory: AKA nondeclarative, procedural – (includes skills and conditioned learning, route – cerebellum -Retrieval: recall versus recognition, relearning; priming – “memoryless memory”; context effects: déjà vu, state-dependent memory, mood-congruent memory -Forgetting: “7 sins of memory” -- forgetting: absent-mindedness, transience, blocking; distortion: misattribution, suggestibility, bias; intrusion: persistence) -encoding failure, storage decay – Ebbinghaus, forgetting curve; retrieval failure – “tip of the tongue phenomenon”, interference: proactive, retroactive; positive and negative transfer, motivated forgetting – Freud / repression; issues (versus suppression…) Memory Construction: Loftus experiment; misinformation effect, imagination, source amnesia / source misattribution, true versus false memory traces, gist memories, children: repressed or constructed memories of abuse??? Improving Memory: overlearning, rehearsal, semantic encoding, mnemonics, retrieval, priming cues, minimize interference, test yourself Chapter 9 – Memory – ‘15 The Phenomenon of Memory – memory definition, Shereshevkii, us; the nature of our memory – flashbulb memories Information Processing – encoding, storage, retrieval; us vs. computers -3 stage processing: sensory memory, short-term / working memory, long-term memory Getting It In: How We Encode: Automatic processing versus effortful processing; rehearsal – Hermann Ebbinghaus overlearning, next-in-line effect, distributed learning / the spacing effect, serial position effect What We Encode: Organizing -visual, acoustic and semantic encoding; self-reference effect, rosy retrospective, imagery – mnemonic devices: method of loci, peg-word, chunking, acronyms, hierarchies What We Retain: Storage Sensory memory: Sperling; iconic, echoic memory Short-term / working memory – length / decay, Miller: “magic 7+/- 2”; Long-term memory – capacity, Rajan Mahadevan… -Storage: AKA memory trace -WHERE? Wilder Penfield, Karl Lashley; -WHAT? Synaptic changes, serotonin, CREB, glutamate, Long-Term Potentiation (LPT); -stress and memory: long versus short-term, amnesia -explicit memory: AKA declarative (includes SEMANTIC and EPISODIC), route -- hippocampus -implicit memory: AKA nondeclarative, procedural – (includes skills and conditioned learning, route – cerebellum -Retrieval: recall versus recognition, relearning; priming – “memoryless memory”; context effects: déjà vu, state-dependent memory, mood-congruent memory -Forgetting: “7 sins of memory” -- forgetting: absent-mindedness, transience, blocking; distortion: misattribution, suggestibility, bias; intrusion: persistence) -encoding failure, storage decay – Ebbinghaus, forgetting curve; retrieval failure – “tip of the tongue phenomenon”, interference: proactive, retroactive; positive and negative transfer, motivated forgetting – Freud / repression; issues (versus suppression…) Memory Construction: Loftus experiment; misinformation effect, imagination, source amnesia / source misattribution, true versus false memory traces, gist memories, children: repressed or constructed memories of abuse??? Improving Memory: overlearning, rehearsal, semantic encoding, mnemonics, retrieval, priming cues, minimize interference, test yourself Chapter 9 Notes: Memory – COMPLETE NOTES VERSION 1 Introduction: Memory allows you to recognize friends, neighbors, and acquaintances and call them by their name; to knit, type, drive, and play the piano, and to speak your language. Our memory accounts for time and defines our life. Everything that we do revolves around some type of memory. You are what you remember. If there was no memory, you would live in an enduring present and even be a stranger to yourself. The Phenomenon of Memory Memory is an indication that learning has persisted over time. It is our ability to store and retrieve information. Suffering a stroke, the ability to make new memories was cut off, while old memories still lingered. On the other hand, Russian journalist S, he only had to listen and would remember everything, didn’t even have to take notes. Your memory is best in a recall of unique and highly emotional points in your past. For example, people remember where they were on Kennedy’s assassination and Princess Diana’s death, and the tragic 9/11 crashes. This perceived clarity for our memories of surprising, significant events leads some psychologists to call them flashbulb memories. But sometimes, even these memories are wrong, such as George Bush mistaking where he was on the morning of 9/11. Information Processing Our memory, in some ways, is like a computer’s information processing system. We must get information into our brain (encoding), retain that information (storage), and later get it back out (retrieval). Same way the computer encodes, stores, and retrieves information. It translates input (keyboard) into an electronic language, such as the brain encoding sensory information into a neural language. Our memories are less literal and more fragile than a computer, of course. We process information in parallel – many things at once. Three – Stage Processing Model – Atkinson and Shiffrin proposed that we first record to-be-remembered information as a fleeting sensory memory, which is later processed into a short-term memory where we encode it through practice for long – term memory and later retrieval. Some information will skip the first two stages and is put into long – term memory automatically – subliminally. We put out attention on certain incoming stimuli – often important ones. These stimuli, along with the information from our long – term memory, become conscious short – term memories. This zone is a site where we rehearse and manipulate information. The content of working memory quickly fades unless we keep using or rehearsing it. Working memory involves both hearing and seeing elements, controlled by a central executive processor. These separate mental subsystems allow us to process images and words at the same time, ex. why we can talk and drive at the same time. The working memory components is the reason why we cant figure out the tune to a song when listening to another. If it is in our working memory, all of the loves work on it (frontal, parietal, and temporal). How We Encode – Automatic Processing You automatically process information about: 1. Space – often encode the place on a page where certain material appears. 2. Time – You unintentionally note the sequenced of the day’s events. Lost your coat, you retrace back your steps to find it. 3. Frequency – you effortlessly keep track of how many times things happen, ex. “I ran into you twice today!” All of this processing goes on without our need to pay attention to it, and you can’t shut it down. Some processing requires attention and effort when we first perform them, but with experience and practice, it becomes automatic. Ex. learning how to read, how to drive. Effortful Processing Learning a chapter in school requires effort and attention. Effortful processing often produces durable and accessible memories through rehearsal, or conscious repeating. Ebbinghaus, scientist of memory, needed to find verbal material that was not familiar. So, he formed a list of all possible nonsense syllables made by putting a vowel between two consonants. The, he would randomly select a sample of syllable and would read aloud, eight times the list. The day after learning the list, he could only recall a few of them. The more frequently he repeated the list aloud on day 1, the fewer repetition he required to relearn the list on day 2. The amount remembered depends on the time spent learning. Even after we learn, additional rehearsal (over learning) increases retention. 1. The next-in-line effect: When people go around a circle saying names or things, their poorest memories are for what was said by the person just before them. 2. Information processes just before sleep is seldom remembered. Consciousness fades before processing information, all is lost. An hour before sleep is well remembered. 3. Taped information during sleep is registered by the ears, but not remembered. “Sleep learning” does not work. We retain information better when our rehearsal is distributed over time (called the Spacing Effect). The longer the space between practice session, the better their retention up to 5 years later. Restudying material for comprehensive final exams, review courses, and senior examinations will enhance lifelong retention. Spreading out learning, rather than over shorter terms – also helps. Those who learn quickly also forget quickly, also – Spaced study beats cramming. Experimenters show people a list of items and have asked them to recall in any order. They struggle and show the serial position effect, remembering the last and first items better than ones in the middle. Ex. In a new job and meeting everyone for the first time, the first names will stick and the middle ones will dry out. What we Encode – Encoding Meaning When processing verbal information for storage, we usually encode its meaning, associating it with what we know. We tend not to remember things as exactly as they were. Rather, we remember what we encoded. When asked to recall what we have read, we talk about the mental model in our heads, not the actual words. Visual encoding (images), Acoustic encoding (sounds), and Semantic encoding (meaning) have their own brain system. Acoustic helps the memory of rhyming anaphorisms. The deeper, semantic encoding, yields much better memory than the shallow processing of acoustic and visual encoding. When something is meaningful and people are familiar with the items, processs, you remember a lot more. That might be why there are benefits to rephrasing what we read. Leaning meaningful material required 1/10 th the effort. We have very good recall for information we can relate to ourselves. To talk about adjectives describing ourselves, we remember the words well – the self – reference effect. Visual Encoding Our earliest memories – something that happened at age 3 or 4 involve visual imagery, mental pictures. We remember concrete words that lead themselves into mental images rather than abstract words. Memory for concrete nouns is aided by encoding them both semantically and visually. We sometimes recall our experiences with metal snapshots of the best and worst moments. Rosy retrospection – where people tend to recall events such as a camping holiday more positively than they thought at the time. Mnemonic – used to remember lengthy passages, imagining themselves moving through a series of locations, associating each place with a topic to be remembered. So, the speech giver would mentally revisit each location. “peg word system” – first memorize a jingle and every word in that jingle will stand for something such as a topic. Organizing Information for Encoding We more easily recall information when we can organize it into meaningful units, or chunks. Chunking occurs naturally that we take it for granted, English learners have a harder time. We all remember information best when we can organize it into personally meaningful arrangements, such as a basketball game. Chunking also aid our recall of unfamiliar material, such as the use of acronyms such as Pemdas for the Order of Operations in math. When people develop expertise in an area, they process information not only in chunks but also in hierarchies composed of a few broad concepts divided and subdivided into narrower concepts and facts. In this way, we retrieve information efficiently. Ex. Taking lecture and text notes in outline format – type of hierarchical organization – may be helpful. Sensory Memory Sperling’s experiment of flashing words at only 1/20th of a second shows that we have a fleeting photographic memory called iconic memory, lasting no more than 1/10th of a second. Delayed signal by more than half a second, iconic memory would be gone. Echoic memory – sensory of auditory stimuli, recalled within 3 or 4 seconds. Ex. “what did I just say?” Working/Short – Term Memory Unless our working memory meaningfully encodes or rehearses that information, it quickly disappears from our short – term memory. Without active processing, short – term memories are limited. Not only is it limited in duration but also in capacity. It only stores seven or so bits of information, which is the capacity. Short – term recall is slightly better for random digits than for random letters, which sometimes have similar sounds. At any given moment, we can consciously process only a very limited amount of information. Long – Term Memory Our capacity for storing long – term memory is limitless. For some time, memory researchers believed that brain stimulation during surgery provided evidence that our whole past is in there. When Penfield electrically stimulated different cortical regions of his patients’ brains, patients heard things and it was because he was activating long – lost experiences, but this was wrong. Memories do not reside in single spots and we do not store most information with the exactness of a tape recorder. Memory trace has been focused on the biological synapses. Synaptic Changes Given increased activity in a particular pathway, neural interconnections strengthen. Increased synaptic efficiency makes for more efficient neural circuits. The sending neuron needs less prompting and the receing neuron’s receptor sites increase. This prolonged strengthening of potential neural firing, (long – term potentiation), providing a neural basis for learning and remembering associations. Drugs that block LTP can’t learn maze but when given LTP, learn it faster. People are competing to develop memory – boosting drugs, the target group being Alzheimer’s disease patients. Boosting CREB production lead to increased production of proteins that reshape synapses and consolidate a short – term memory into a long – term memory. You can also boost glutamate, which enhances synaptic communications. Stress Hormones and Memory The stress hormone that people produce is glucose, to fuel the brain. Also, the amygdale boosts activity. Arousal can sear certain events into the brain, while disrupting memory. Stronger emotional experiences make for stronger, reliable memories. Weaker emotion makes wear memories. This is why we remember exciting or shocking events better. But, there are limits to stress – enhanced remembering. Prolonged stress, can act like an acid, corroding neural connections and shrinking a brain area (hippocampus) that is vital for laying down memories. Storing Implicit and Explicit Memories Amnesia – which people are unable to form new memories. Jimmie had brain damage, had no memories which meant no sense of time. Although incapable of recalling new facts or anything they have done recently, but they can learn. They can learn and solve puzzles through learning without awareness of having learned them. In some ways, they are people who cannot recognize faces but shown familiar faces, have an unconscious recognition. Because of this, it seems that we have two memory systems. They can learn how to do something (implicit memory/ procedural memory) but not know and declare that they know (explicit memory/ declarative memory).New explicit memories of names, images, and events are laid down via the hippocampus, a neural center in the limbic system. When forming a memory, they reveal activity in hippocampus as well as in certain areas of the frontal lobes. Damage to the hippocampus disrupts things; damage to the left is having trouble remembering verbal information, while the right has trouble recalling designs and locations. In hippocampus, one part is active in names with faces, while others in spatial arrangements. If people lose hippocampus to surgery, they lose most of their recall for things learned during the preceding month. The greater the hippocampus activity during sleep after a training experience, the better the next day’s memory. Our memories are not in one place, many brain regions are active as we encode, store, etc. The cerebellum plays a key role in forming and storing the implicit memories created by classical conditioning, such as being pricked by a doctor accidentally under hand and not wanting to shake hands afterward. Humans with a damaged cerebellum are incapable of developing certain conditioned reflexes. Implicit memory formation needs the cerebellum. Retrieval: Getting Information Out To most people, memory is recall, the ability to recognize information not in conscious awareness. Long after not being able to recall most of the people in a yearbook, you can still recognize their yearbook picture from a photograph lineup and pick their names from a list of names. They couldn’t recall any but they could recognize 90% of their pictures and names. Relearning – memory measure that assesses the amount of time saved when learning material for a second time. Our recognition memory is impressively quick and vast. Retrieval Cues When you encode into memory a target piece of information, you associate with it other bits of information about your mood, surroundings, etc. This other information are like tags, hints, or marks on the information bit. The best retrieval cues, not the mnemonic devices, but the association formed at the time we encode a memory, and those cues can be experiences as well as words. To retrieve a specific memory from the web of association, you need to activate one of the strands leading to it, process called priming. Priming is often “memory less memory” – invisible memory. Context Effects When you need to sharpen pencil, you might go into another room and wonder why you are there. Then, when you go back, the pencil comes back to your mind. These are called context effects. Sometimes, being in a context similar to one we’ve been in before may trigger the experience of déjà vu – the eerie sense of “Ive been here before” . It happens most commonly to well – educated, imaginative young adults. So, if in a similar context you see a stranger who looks and walks like one of your friends, the similarity may give rise to the eerie feeling of recognition. A situation can also seem familiar when moderately similar to several events. Imagine meeting a family, you might have dejavu meeting the cousin. Moods and Memories An emotion is like a library room into which we place memory records. What we learn in one state – joyful, sad, drunk, sober – is sometimes more easily recalled when we are again in that state, called state – dependant memory. We seem to associate good or bad events with their emotions, which are retrieval cues. So, our memories are mood- congruent. Being depressed sours memories by giving negative associations, and vice versa. Depressed people recall their parents as rejecting, punitive, etc because of this. Moods also influence how we interpret other people’s behavior. Being mindful of our feelings can help us correct for the mood bias. When happy, you recall happy events and when sad, recall sad moments. Forgetting A good memory is helpful, but so is the ability to forget. The seven ways our memory fails us: 1. Absent – mindedness – inattention to details produces encoding failure (mind is elsewhere as we lay down car keys) 2. Transience - storage decay over time (part way with people, unused information fades) 3. Blocking – inaccessibility of stored information (see old classmate, feel name on tip of tongue 4. Misattribution – confusing the source of information (putting words in someone else’s mouth 5. Suggestibility – effects of misinformation 6. Bias – belief – colored recollections 7. Persistence – unwanted memories Encoding Failure We cannot remember what we fail to encode, because the information never enters long – term memory. Much of what we sense, we never notice. An example of encoding failure is the recognition of pennies. In the figure of 15 pennies, most people cannot recognize the real penny. The details of a penny are not meaningful, nor are they essential and so; few of us have made efforts to encode them. Storage Decay Forgetting Curve – indicates that much of what we learn we may indeed quickly forget. The course of forgetting is initially rapid, and then levels off with time. Compared with people just completing a high school Spanish course, people who had been out of school for 3 years had forgotten much of what they had learned. After 3 years, it leveled off. One explanation for this is a gradual fading of the physical memory trace. Even if memories are stored and available, it may be inaccessible. Perhaps, you lack the information needed to open it up and retrieve it. Ex. The name on the tongue. Forgetting is often not memories discarded but memories unretrieved Interference Learning some items may interfere with retrieving others, especially when the items are similar. Such proactive (forward – acting) interference occurs when something you learned earlier disrupts your recall of something you experience later. Retroactive (backward – acting) interference occurs when new information makes it harder to recall something you learned earlier. You can minimize retroactive interference by reducing the number of interfering events, going for a walk or sleep shortly after learning something new. Forgetting occurred more rapidly after being awake and involved with other activities. Interference is an important cause of forgetting; why ads viewed during violent or sexual TV programs are so forgettable. But, this is not always true in the case of knowing Latin can help you learn French – positive transfer. Motivated Forgetting People unknowingly revise their own histories. To remember our past is often to revise it. With his concept of repression, Freud proposed that our memory systems do indeed self – censor painful information. To protect our self – concept and to minimize anxiety, we supposedly repress painful memories. The submerged memory lingers can be retrieved by some later cue or during therapy. Misinformation and Imagination Effects – Memory Construction We often construct our memories as we encode them, and we may also alter our memories as we withdraw them from our memory bank. In a car accident report, when asked how fast they hit/smash to each other – the smashed participants gave higher estimates. People have witnessed an event, received or not received misleading information about it, and then taken a test and the repeated result is a misinformation effect. After exposure to subtle misinformation, many people misremember. As a memory fades with time following an event, misinformation becomes easier. As we recount an experience, we fill in memory gaps with plausible guesses and assumptions. After more retellings, we often recall the guessed detail, which have now been put into our memories. Even repeatedly imagining nonexistent actions and events can create false memories .Imagined events seem more familiar and familiar things seem more real. Thus, the more vividly people can imagine thing, the more likely they are to inflate their imaginations into memories. Even psychologists are not immune to memory construction. Source Amnesia When we encode memories, we distribute different aspects of them to different parts of the brain. Among the frailest parts of a memory is its source, ex. Not knowing where you have seen a person. Source Amnesia – attributing to the wrong source an event we have experience, heard about, read about, or imagined. Discerning True and False Memories Unreal memories can feel like real memories. Memories are akin to perceptions – perceptions of the past. People’s initial interpretations influence their perceptual memories. We also cannot judge a memory’s reality by its persistence. Memories we derive from experience have more detail than memories we derive form imagination. Memories of imagined experiences are more restricted to the gist of the supposed event. Gist memories are durable and when therapists ask for this, they have the chance of getting false memories. False memories created by suggested misinformation and misattributed sources may feel as real as true memories, and very persistent. The most confident and consistent eyewitnesses are the most persuasive, but not the most accurate. This type of misinformation can lead to the idea of people getting sent to the police because they look like a rapist or a wanted person. Children’s Eyewitness Recall In the cases of sexual abuse, interviewers who ask leading questions can plant false memories. Children tend to be suggestible, and so, they can be induced to report false events. Nevertheless, if questioned about their experience in neutral words they understand, children often accurately recall what happened and who did it. 4 – to 5 year old children produce more accurate recall. Children are especially accurate when involved adults have not talked with them prior to the interview an when their disclosure is made in a first interview. Given such detailed stories, professional psychologists who specialize in interviewing children were often fooled. They could not reliably separate real memories from false ones. Repressed or Constructed Memories of Abuse? Many patients exposed to such techniques (such as “you were probably abused” do form an image of a threatening person. With further visualization, the image grows more vivid, leaving the patient stunned, angry, and ready to confront or sue the equally stunned and devastated parent, relative, or clergy member. The presumed abuser then vigorously denies the accusation. Those committed to protecting abused children and those committed to protecting wrongly accused adults agree on the following: 1. Injustice happens – some innocent people have been falsely convicted. 2. Incest and other sexual abuse happen. 3. Forgetting happens – abused children can forget their traumatic experience. 4. Recovered memories are commonplace. 5. Memories “recovered” under hypnosis or the influence of drugs are especially unreliable. 6. Memories of things happening before age 3 are unreliable. 7. Memories, whether real or false, can be emotionally upsetting. Improving Memory 1. Study repeatedly to boost long – term recall 2. Spend more time rehearsing or actively thinking about the material 3. Make the material personally meaningful 4. To remember a list of unfamiliar items, use mnemonic devices,. 5. Refresh your memory by activating retrieval cues. 6. Recall events while they are fresh, before you encounter possible misinformation. 7. Minimize interference 8. Test your own knowledge, both to rehearse it and to help determine what you do not yet know. Without self – testing, one can easily become overconfident. “To be conscious that you are ignorant is a great step to knowledge.” Chapter 9 Outline – COMPLETE NOTES VERSION 2 The Phenomenon of Memory Memory: the persistence of learning over time through the storage and retrieval of information. Memory is any indication that learning has persisted. It is out ability to store and retrieve information. Memory Loss and Memory Feats Russian Journalist Shereshevskii called S by his psychologist. His memory allowed him merely to listen while other reporters were scribbling notes but it also earned him a place in virtually every modern book on memory. S could repeat up to 70 digits or words, which were 3 seconds apart in a silent room. He could recall them backward as easily as forward. Your memory capacity is the most apparent in your recall of unique and highly emotional moments in your past. Flashbulb Memories: a clear memory of information into the memory system-for example, by extracting meaning. Information Processing Encoding: the processing of information into the memory system-for example, by extracting meaning. We get information into our brain to remember any event. Storage: the retention of encoded information over time. We retain that information. Retrieval: the process of getting information out of memory storage. Then we later get it back out. A computer first translates input into an electronic language then permanently stores information on a disk, from which it can later be retrieved. Atkin and Shiffrin’s three-stage processing model of memory, which suggests we give birth to memories through 3 stages. The First Stage. Sensory Memory: the immediate, initial recording of sensory information in the memory system. Second Stage. Short-Term Memory: activated memory that holds a few items briefly, such as the 7 digits of a phone number while dialing, before the info is stored or forgotten. Third Stage. Long-Term Memory: the relatively permanent and limitless storehouse of the memory system. This three-stage process is limited and fallible. A newer concept of working memory clarifies the shortterm memory concept by focusing more on how we attend to, rehearse, and manipulate info in temporary storage. Encoding: Getting Information In How We Encode Automatic Processing: unconscious encoding of incidental information, such as space, time, and frequency, and of well-learned information, such as word meanings. This is your memory for the route you walked to your last class. Effortful Processing: encoding that requires attention and conscious effort. This is your learning of this chapter’s concepts. Automatic Processing Often with little or no effort we can encode enormous amount of info about space, time, and frequency. Example: during a test you may recall the place on the textbook page where forgotten material appears. Some types of automatic processing we learn sometimes require effort at first. After practice, some effortful processing becomes more automatic. Occurs with little or no effort, without our awareness, and without interfering with out thinking about other things. Effortful Processing We encode and retain vast amounts of information automatically, but we remember other types of info only with effort and attention. Rehearsal: the conscious repetition of information, either to maintain it in consciousness or to encode it for storage. Hermann Ebbinghaus was to the study of memory what Ivan Pavlov was to the study of conditioning. He decided to study it scientifically and chose to study his own learning and forgetting of novel verbal material. Ebbinghaus needed to find verbal material that was not familiar so he randomly selected a sample of syllables. After a day of learning the list he could recall a few. The first day he repeated the list aloud. Day 2 he needed fewer repetitions, the principle of the amount remembered depends on the time spent learning was used. Practice-effortful processing- does make perfect. Next-in-line effect: people go around a circle reading words or saying their names; their poorest memories are for what was said by the person just before them. When next in line we focus on our own performance and often fail to process the last Information presented in the seconds just before sleep seldom is remembered. Information presented in the hour before sleep is well remembered. Sleep-learning doesn’t occur. Spacing Effect: the tendency for distributed study or practice to yield better long-term retention than is achieved through massed study or practice. We retain information better when our rehearsal is distributed over time. Harry Bahrick and 3 of his family member practiced foreign language word translations for a given number of times, at intervals from 14 to 56 days in a 9-year experiment. They found that the longer the space between practice sessions, the better their retention up to 5 years later. Restudying material for comprehensive final exams, capstone review courses, and senior examinations will enhance lifelong retention. Spaced studying beats cramming. Thomas Laundaure-“Rehearse the name or number you are trying to memorize, wait a few seconds, rehearse again, wait a little longer, rehearse again, then wait longer still and rehearse yet again. The waits should be as long as possible without losing the information.” Serial Position Effect: our tendency to recall best the last and first items in a list. People remember the last and first items better than they do those in the middle. Rehearsal will encode all information equally well. Sometimes merely repeating information is not enough to store it for later recall. What We Encode We process information in 3 key ways-by encoding its meaning, by visualizing it, and by mentally organizing it. Encoding Meaning When processing verbal info for storage, we usually encode its meaning. We associate it with what we already know or imagine. We remember what we encode. Visual Encoding: the encoding of picture images. Acoustic Encoding: the encoding of sound, especially the sound of words. Semantic Encoding: the encoding of meaning, including the meaning of words. Acoustic Encoding enhances the memorability and seeming truth of rhyming aphorisms. Craik and Tulving flashed a word at people to compare visual, acoustic, and semantic encoding. They asked questions that required the people to process the words (1) visually (the appearance of the letters), (2) acoustically (the sound of the words), (3) semantically (the meaning of the words). Ebbinghaus estimated that learning meaningful material required only one-tenth the effort compared with learning nonsense material. We have excellent recall for info we can relate to ourselves. When asked how well certain adjectives describe someone else, we will forget them and when asked to rate how well the adjectives describe ourselves, we remember the words well. This is called self-reference effect. Encoding Imagery Imagery: mental pictures; a powerful aid to effortful processing, especially when combined with semantic encoding. Researchers have documented the benefits of mental images. We remember words that lend themselves to picture images better than we remember abstract, low-imagery words. We recall our experiences with mental snapshots of their best of worst moments. Terry Mitchell, Leigh Thompson, Eirka Peterson, and Randy Cronk have discovered a phenomenon called Rosy Retrospection, people tend to recall events such as a camping holiday more positively than they evaluated them at the time. Mnemonic: memory aids, especially those techniques that use vivid imagery and organizational devices. Remembering lengthy passages and speeches. “Method of loci”- imagine themselves moving through a familiar series of locations, associating each place with a visual representation of the to-be-remembered topic. Then when they were speaking the orator would mentally revisit each location and retrieve the associated image. Other mnemonic devices involve both acoustic and visual codes. The “peg-word” system requires that you first memorize a jingle: “One is a bun; two is a shoe, three is a tree, four is a door; five is a hive, six is sticks; seven is heaven; eight is a gate; nine is swine; ten is a hen.” Without effort you will be able to count by peg-words instead of numbers. Organizing Information for Encoding Meaning and imagery enhance our memory by helping us organizing information. o Chunking Chunking: organizing items into familiar, manageable units; often occurs automatically. o If a native speaker you can reproduce perfectly the 150 or so line segments that make up the words in three phrases. We all remember information best when we can organize it into personally meaningful arrangements. Acronyms are words or sentences from the first letter of words to be remembered. If you want to recall the names of North America’s five Great Lakes, just remember HOMES (Huron, Ontario, Michigan, Erie, Superior). You can also recall digits with chunking. After more than 200 hours of practice in the lab of Ericsson and Chase, two students managed to increase their memory span from 7 digits to more than 80. Hierarchies Donatellis peak-106 digits- retrieved the chunks of numbers by clustering them as a hierarchy. First came “three groups of four” etc. Hierarchies are composed of a few broad concepts divided and subdivided into narrower concepts and facts. Bower and his colleagues demonstrated benefits of hierarchical organization. They presented words randomly or grouped into categories. Recall was better. Storage: Retaining Information Sensory Memory Our sensory memory is the initial recording of sensory information in the memory system. Sperling showed people three rows of three letters each for only 1/20th of a second. It was harder than reading by flashes of lightning. After the nine letters disappeared from the screen, people could only recall half. He would sound a high, medium, or low tone immediately after flashing the nine letters and now they rarely missed a letter. Ionic Memory: a momentary sensory memory of visual stimuli; a photographic or picture-image memory lasting no more than a few tenths of a second. For an instant, our eyes register an exact representation of a scene and we can recall any part of it. Echoic Memory: a momentary sensory memory of auditory stimuli; if attention is elsewhere, sounds and words can still be recalled within 3 or 4 seconds. Short-Term Memory We retrieve information from long-term storage for “on-screen” display but unless we meaningfully encode or rehearse that information, it disappears. Lloyd Peterson and Margaret Peterson asked people to remember three-constant groups, such as CHJ. To prevent rehearsal of the letters, the researchers asked participants to start at 100 and count aloud backwards by threes. After 3 seconds, people recalled he letters only about half the time; after 12 seconds, they rarely recalled them at all. Short-term memory is limited in duration and also in capacity. Our short-term memory typically stores just 7 bits of info. Miller enshrined this recall capacity as the Magical Number Seven, plus of minus two. Short-term memory recall is slightly better for random digits than for random letters. Better for info we hear than for images we see. Basic Principle: at any given moment, we can consciously process only a very limited amount of information. Long-Term Memory Our capacity for storing lone-term memories is essentially limitless. The average adult has about a billion bits of info in memory and a storage capacity that is a thousand to a million times greater. Rajan Mahadevan, a psychologist, if given a block of 10 digits from the first 30,000 or so digits of pi and, after a few moments of mental searching for the string, he’ll pick up the series from there, firing numbers like a machine gun. He can also repeat 50 random digits backwards. Storing Memories in the Brain For a time some researchers believed that brain stimulation during surgery provided evidence that our whole past is “in there”, in complete detail, just waiting to be relieved. “Everything we learn is permanently stored” although sometimes inaccessible. Penfield helped map the brain’s motor cortex by electrically stimulating wide-awake patients. Occasionally his patients would report hearing things as “a mother calling her little boy.” Penfield assumed he was activating long-lost experiences etched permanently in the brain. Elizabeth Loftus and Geoffrey Loftus discovered that these flashbacks were extremely rare and occur in only a handful of Penfield’s 1100 stimulated patients. What is “memory trace”? Karl Lashley trained rats to solve a maze, and then cut out pieces of the rats’ cortexes and retested their memory of the maze. No matter what small cortex section he removed, the rats retained at least a partial memory of how to solve the maze. His conclusion: Memories do not reside in single, specific spots. Ralph Gerard first trained hamsters to turn right or left to get food and then lowered their body temperature until the brain’s electrical activity ceased. When revived they would remember which way to turn. Synaptic Changes Memories begin as impulses whizzing through brain circuits. The sites where nerve cells communicate with one another through their neural networks. Eric Kandel and James Schwartz observed changes in the sending neurons of a simple animal, the California sea snail, Aplysia. After observing, they pinpointed changes. When learning occurs, the snail releases more of the neurotransmitter serotonin at certain synapses. Increased synaptic efficiency makes more for efficient neural circuits. Long-Term Potentiation: an increase in a synapse’s firing potential after brief, rapid stimulation. Believed to be a neural basis for learning and memory. Provides a neural basis for learning and remembering associations. Drugs that block LTP interfere with learning. Drugs given to mice that enhance LTP will learn a maze with half the usual number of mistakes. Neuroscientists were discovering protein molecules that serve to build synaptic connections and enhance long-term memory. These findings raise hopes that researchers may someday discover drugs or “brain-specific” nutrients to enhance human memory, especially for those whose memory is fading. Stress Hormones and Memory The naturally stimulating hormones that humans and animals produce when excited or stressed also affect learning and retention-they boost it. Making more glucose energy available to fuel brain activity, the hormone surge signals the brain that something important has happened. The amygdala boosts activity in the brain’s memory-forming areas. Weaker emotions mean weaker memories. Emotion-triggered hormonal changes help explain why we long remember exciting or shocking events. McGaugh: “stronger emotional experiences make for stronger, more reliable memories.” Prolonged stress acts like acid, corroding neural connections and shrinking a brain area (hippocampus) that is vital for laying down memories. Storing Implicit and Explicit Memories Amnesia: the loss of memory. Unable to form new memories. Oliver Sacks describes one patient, Jimmie, who had brain damage; he had no memories and thus, no sense of elapsed time. When looking in a mirror he couldn’t believe he had aged, he thought he was 19. They are like people with brain damage who cannot consciously recognize faces but whose psychological responses to familiar faces reveal an unconscious recognition. Implicit Memory: retention independent of conscious recollection. Also called procedural memory. Can learn how to do something. Explicit Memory: memory of facts and experiences that one can consciously know and “declare.” Also called declarative memory. May not know and declare that they know. Reading a story once they will read it faster a second time-implicit memory. There will be no explicit memory, they cannot recall having seen the story before. o The Hippocampus Hippocampus: a neural center located in the limbic system that helps process explicit memories for storage. Damage to the hippocampus disrupts some types of memory. It is lateralized. Damage to the left or right hippocampus seems to produce different results. Patients with left hippocampus damage have trouble remembering verbal information, but have no trouble recalling visual designs and locations. The problem is reversed when the right side is damaged. It seems to act as a convergence zone where the brain registers and temporarily stores the elements of a remembered episode. Our memories are not in one place. o The Cerebellum Hippocampus is a temporary processing site for your explicit memories, you could lose it and still lay down memories for skills and conditioned associations. Joseph Le Doux recounts a brain-damaged French patient whose amnesia left her unable to recognize her physician as, each day; he shook her hand and introduced himself. Richard Thompson, David Krupa, and Judith Thompson studied how a rabbit’s brain learns to associate a tone with an impending air puff in the eye. They discovered that it runs to the brainstem through a part of the cerebellum and that it cut this pathway, the learned response would be lost. Human patients with a damaged cerebellum are likewise incapable of simple eyeblinking conditioning. Emotional memories involve the amygdala. Retrieval: Getting Information Out Recall: a measure of memory in which the person must retrieve information learned earlier, as on a fill-in-the-blank test. Retrieve info not in conscious awareness. Recognizing or quickly relearning info also indicates memory. You can recognize an old classmate. Recognition: a measure of memory in which the person need only identify items previously learned, as on a multiple-choice test. Relearning: a memory measure that assesses the amount of time saved when learning material for a second time. We remember what we recall. Retrieval Cues Retrieval Cues provide reminders of information we could not otherwise recall. They also guide us to where to look. Priming: the activation, often unconsciously, of particular associations in memory. William James referred to priming as the “wakening of associations.” Priming has been called “memoryless memory”-memory without remembering invisible memory. If walking down a hallway, you see a poser of a missing child; you will be “primed” to interpret an ambiguous adult-child interaction as possible kidnapping. Retrieval cues often prime our memories of earlier experiences. Tastes, smells, and sights often evoke our recall of associated episodes. Context Effects Déjà vu: the eerie sense that “I’ve experience this before.” Cues from the current situation may subconsciously trigger retrieval of an earlier experience. Many of who report having this experience often wonder how they could recognize a situation that they are experiencing for the first time. Some think of reincarnation. If asked why do I feel as if I recognize this situation then can see how our memory system might produce déjà vu. Previously been in a similar situation. Lampinen suggests that a situation seems familiar when moderately similar to several events. Moods and Memories Events in the past may have aroused a specific emotion that later can prime us to recall its associated events. Gordon Bower, cognitive psychologist, explained it this ay: “An emotion is like a library room into which we place memory records. We best retrieve those records by returning to that emotional room.” What we learned in one state can be easily recalled when we are again in that state, this is called state-dependent memory. What people learn when depressed or drunk don’t recall well in any state. Mood-Congruent: the tendency to recall experiences that are consistent with one’s current good or bad mood. Being depressed sours memories by priming negative associations. We should not be surprised that in some studies currently depressed people recall their parents as rejecting, punitive, and guilt promoting, were as formerly depressed people describe their parents much as do those who have never suffered depression. Moods influence how we interpret other people’s behavior. Forgetting Daniel Schacter, memory researcher, enumerated seven ways our memories fail us-seven sins of memory. Three sins of forgetting: o Absent-mindedness-inattention to details produces encoding failure (our mind is elsewhere as we lay down the car keys). o Transience-storage decay over time (unused information fades). o Blocking-inaccessibility of stored information (it may be on the tip of our tongue, but we experience retrieval failure-we cannot get it out). Three sins of distortion: o Misattribution-confusing the source of information (putting words in someone else’s mouth or remembering a movie scene as an actual happening). o Suggestibility-the lingering effects of misinformation (a leading question-“Did Mr. Jones touch your private parts?”- later becomes a young child’s false memory) o Bias-belief-colored recollections (someone’s current feelings toward their fiancé may color their recalled initial feelings). One sin of intrusion: o Persistence-unwanted memories (being haunted by images of a sexual assault) Encoding Failure What causes us to forget: we failed to encode the information. It never entered long-term memory. Age can affect encoding efficiency. No matter how young we are, we selectively attend to a few things. Think about these few questions: What letters accompany the number 5 on your telephone? Where is the number 0 on your calculator? For most these questions are difficult. We encode some information automatically and other types require effortful processing. Without effort, many memories never form. Storage Decay Even after encoding we may later forget. Ebbinghaus learned more lists of nonsense syllables and measured how much he retained when relearning each list, from 20 minutes to 30 days later. His “forgetting curve” says that much of what we learned may be quickly forgotten. Later it was said that: The course of forgetting is initially rapid, then levels off with time. Harry Bahrick extended Ebbinghaus’ finding and examined the forgetting curve for Spanish vocabulary learned in school. Most people who had been out of school for 3 years had forgotten much of what they had learned. After 3 years, their forgetting leveled off; what people remembered then, they still remembered 25 and more years later. One explanation is a gradual fading of the physical memory trace. Memories also fade because of the accumulation of other learning that disrupts our retrieval. Retrieval Failure When we fail to encode information and when our stored memory decays we forget. Forgotten events are like books you can’t find in your campus library-some because they were never acquire, others because they were discarded. However, even if the book is stored and available it may be out of reach. Forgetting is memories unretrieved. Interference Proactive (forward-acting) Interference: the disruptive effect of prior learning on the recall of new information. Occurs when something you learned earlier disrupts your recall of something you experience later. The first time you park at your local mall parking lot you will have no trouble returning to your car. After parking many times you may. Retroactive (backward-acting) Interference: the disruptive effect of new learning on the recall of old information. Occurs when new information makes it harder to recall something you learned earlier. Learning new students’ names typically interferes with a teacher’s recall of the names of previous names. John Jenkins and Karl Dallenbach discovered the sleep benefit in an experiment. Day after day, 2 people learned some nonsense syllables and then tried to recall them after up to 8 hours of being awake or asleep at night. “Forgetting is not so much a matter of the decay of old impressions and associations as it is a matter of interference, inhibition, or obliteration of the old by the new”. An hour before a night’s sleep is a good time to commit information to memory. Interference is an important cause of forgetting. Sometimes old information can facilitate our learning of new info. Knowing Latin may help us learn French, which is a positive transfer. When old and new information compete with each other that interference occurs. Motivated Forgetting Repression: in psychoanalytic theory, the basic defense mechanism that banishes from consciousness anxiety-arousing thoughts, feelings, and memories. Sigmund Freud proposed that our memory systems do self-censor painful information. We repress painful information to protect our self-concept and to minimize anxiety. However, the submerged memory lingers and with patience and effort may be retrieved by some later cute or during therapy. Repression was central to Freud’s psychology and became part of psychology’s lore. Memory Construction We have an enormous capacity for storing and reproducing the incidental details of our daily experience. We often construct our memories as we encode them, and we may also alter our memories as we withdraw them from the memory bank. Misinformation and Imagination Effects Elizabeth Loftus has shown how eyewitnesses similarly reconstruct their memories when questioned. In an experiment with John Palmer, she showed people a film of a traffic accident and then quizzed them about what they saw. Some were asked how fast the cars were going when they smashed into each other and many gave a higher speed. A week later, researchers asked the viewers if they recalled seeing any broken glass and the ones that would more than twice likely say yes were the ones that were asked if the cars had smashed. Misinformation effect: incorporating misleading information into one’s memory of an event. After exposure to subtle misinformation, many people misremember. People later find it nearly impossible to discriminate between their memories of real and suggested events because of the misinformation effect. Imagining nonexistent actions and events can create false memories. Students who repeatedly imagined simple acts such as breaking a toothpick or picking up a stapler later experience “imagination inflation”; they were more likely to think they had actually done such things during the experiment’s first phase. Imagined events later seem more familiar, and familiar things seem more real. The more vividly people can imagine things; the more likely they are to inflate their imaginations into memories. Source Amnesia We may recognize someone but have no idea where we have seen the person. Source Amnesia: attributing to the wrong source an event that we have experienced, heard about, read about, or imagined. (Also called source misattribution). It is at the heart of many false memories. Poole and Lindsay replicated Piaget’s source amnesia. They had preschoolers interact with “Mr. Science,” who engaged them in demonstrations such as bowling up a balloon with baking soda and vinegar. Three months later they were read a story about themselves and Mr. Science. When asked questions by someone new 4 in 10 children recalled Mr. Science doing things that were only done in the story. Discerning True and False Memories Jamin Halberstadt and Paul Niedenthal show people’s initial interpretations influence their perceptual memories. They invited students to view morphed faces that expressed a mix of emotions. They asked to imagine and explain, “why this person is feeling angry” (or happy). Half hour later the participants view a computer showing a morphed transition from the angry to happy face and then were asked to slide a bar to change the face’s expression until it matched the expression as earlier seen. Those who explained anger recalled the face as angrier than those who had explained happiness. Memories of imagined experiences are more restricted to the gist of the supposed event- the meanings and feelings we associate with it. Gist memories are durable; children’s false memories sometimes outlast their true memories. False memories are created by suggested misinformation and may feel as real as true memories the brain scans tell something else. If asked to read aloud a list of words and later asked to recognize the words from a larger list you would err three out of four times. Henry Roediger and Kathleen McDermott. Although people could not tell the difference between their true and false memories, their brains could. Memory construction helps explain why “hypnotically refreshed” memories of crimes so easily incorporate errors. It explains why dating partners who fall in love overestimate their first impressions of one another, while those who break up underestimate their earlier liking. Children’s Eyewitness Recall Children sometimes are credible eyewitnesses in criminal cases, but they tend to be suggestible. Preschoolers were more suggestible than older children or adults. If questioned about their experiences in words they understand, children often accurately recall what happened and who did it. They are especially credible when involved adults have not talked with them prior to the interview. Studies of children’s recollections of physical examinations illustrate both their reasonable accuracy and occasional lapses. Repressed or Constructed Memories of Abuse? Traumatic events are sometimes forgotten, aided by the toxic effects of sustained stress. 38 percent of those interviewed-who did not spontaneously recall the specific reported incident of their own abuse. Jennifer Freyd, a cognitive psychologist, theorizes that memories may remain vivid for life-threatening traumas such as a hurricane or car accident, yet be dulled or blocked for traumas that involve repeated betrayal. The average therapist believes that 11 percent of the population-some 34 million people-have repressed memories of childhood sexual abuse (but this is in the context of hypnosis / guided imagery therapy, which can produce false memories – the point was that this is probably too high [see page 378]). Those committed to protecting abused children and those committed to protecting wrongly accused adults agree on these: o Injustice happens. Some innocent people have been falsely convicted and that some guilty people have evaded responsibility by casting doubt on their truth-telling accusers. o Incest happens. It happens more often than we suppose and there is no characteristic “survivor syndrome”. Sexual abuse can leave its victims predisposed to problems ranging from sexual dysfunction to depression. o Forgetting happens. Circumstances under which forgetting is “utterly common.” Forgetting isolated past events, both negative and positive, is an ordinary part of life. o Recovered memories are commonplace. We recover memories of long-forgotten events when cued by a remark or an experience. o Memories “recovered” under hypnosis or the influence of drugs especially unreliable. Infantile Amnesia is a phenomenon where people do not reliably recall happenings of any sort from their first 3 years. o Memories, whether real or false, can be emotionally upsetting. If a false memory becomes a real part of one’s history that person may suffer. Ingredients for cooking false memories: a credible authority, repeated suggestions, imaginationenhancing techniques, and affirmation for one’s budding suspicions. Improving Memory We forget people’s names, or forget to bring up a point in a conversation, etc. The PRTR-preview, read, think critically, review-incorporates these strategies: o Study repeatedly to boost long-term recall. Overlearn, for learning a name keep saying it to yourself after you know it and then wait a while and say it again. Have many separate study sessions. o Spend more time rehearsing or actively thinking about the material. Rehearsal and critical reflection helps more than speed-reading complex material. o Make the material personally meaningful. Take thorough text and class notes in your own words. Mindless repeating is ineffective. Form images, organize info, relate material to what you already know, put it into your own words. o To remember a list of unfamiliar items, use mnemonic devices. Use peg-words. Make up a story that incorporates vivid images of the items. Use acronyms. o Refresh your memory by activating retrieval cues. Re-create the situation and the mood in which the original learning occurred mentally. o Recall events while they are fresh, before you encounter possible misinformation. Record your memory before allowing others to suggest what happened if you are an eyewitness to an event. o Minimize inference: study before sleeping. Do not study similar subjects at the same time because they may interfere with each other, such as Spanish and French. o Test your own knowledge, both to rehearse it and to help determine what you do not yet know. Test your recall. Outline sections on a blank page. Define concepts listed at each chapter’s end before turning back to their definitions. Practice tests, study guides, etc. Do not be over-confident.
