Cognitive Processes:Memory and Problem Solving Chapters 8 and 9
Memory Defined and The Information Processing Model • Defining Memory • The persistence of learning over time through storage and retrieval of information • Much of what we have learned about memory comes from cases of memory loss or extraordinary memory • Russian journalist Shereshevsky (case reading) • Today, memory is often seen as steps in an information-processing model • Encoding • Storage • Retrieval • Information Processing is similar to how computer works
3 Stages of Memory FormationAtkinson and Shiffrin (1968) • Initial recording of information as fleeting sensory memory (1) • Processing of this information in short-term memory (STM), where we encode it through rehearsal (2) • Also known as working memory • We process what we pay attention to of all the incoming sensory stimuli we are bombarded with • Working memory also associates new information with old information from LTM • Moving of information into more permanent long-term memory (LTM) for later retrieval (3) • Memory ability varies from person to person • Those with better working memories tend to exhibit high intelligence • Those with better memories tend to maintain better focus on tasks
Automatic Processing • Because the brain engages in parallel processing, it automatically gathers information about many things without us even knowing! • Space – automatically recalling where a term was on a slide • Time – automatically recalling the sequence of events • Frequency – automatically keeping track of how many times you have done something • Well-learned information – automatic processing of very familiar information like words we know • New tasks that may begin as effortful can become automatic if we expose ourselves enough!
DEMO • DO NOT write down the following list. Listen and read them, then try to recall them when prompted: • CLINTON • RUJ • FET • TEXTBOOK • NAV • BUSH • FULFILL • GEF • MANDATE • FET • 47 • TAL
Effortful Processing • While some information is automatically and effortlessly processed, some requires focus and attention • Attention is defined as selection certain information for further processing • We normally pay attention to only a small portion of incoming information • We pay attention to things according to… • Meaningfulness • Distinctiveness • Repetition • Broadbent’s Cocktail Party Phenomenon: we tune out other sounds to focus on what is important
Memory:Ebbinghaus’ Contributions • Can increase memory ability through rehearsal • Hermann Ebbinghaus scientifically studied his own memory of verbal information in the 19th century. • Memorized a list of nonsense syllables • The more he rehearsed, the more he remembered • The more time spent on learning, the more we remember • One of the important memory phenomena discovered by Ebbinghaus is the overlearning effect. • continue to practice memorizing a list beyond that required to produce two perfect recalls. • For example, if it required 10 repetitions to memorize the list, then you might continue for an additional ten repetitions -- this would be "100% overlearning." • The effect of overlearning is to make the information more resistant to disruption or loss.
Memory:Ebbinghaus’ Contributions The more the syllables were rehearsed (praticed) on the first day of learning, the fewer rehearsals it took to relearn them on the second.
Making Memories Last… This is sooooo much fun! I will do it every night until the test! • Information quickly learned is information quickly lost! • Spacing Effect: distributed study time yields better long-term retention than massed practice (cramming)! • Testing Effect: more frequent quizzing or previously studied material yields better long-term retention • Bottom line: spread your studying out over time and quiz yourself frequently! Unless evil clowns stop you!
The Serial Position Effect:Benefits of Rehearsal + Working Memory • When we are given a list of things to remember, we often remember the first items and last items on the list. • This is called the serial position effect. • We are able to rehearse those at the beginning the most and those at the end are still in our working memory! • Primacy Effect: tendency to recall the first items on the list • Recency Effect: tendency to recall the last items on the list
What We Encode:Levels of Processing • When we hear the sounds that comprise words, we use context and experience to determine meaning. • E.g. “Eye-Screem” – is it “ice cream” or “I scream”? • We tend not to remember literally what we read or heard, but rather the general meaning • We use several types of encoding to process verbal information • Visual (structural) encoding of images • Acoustic (phonetic) encoding of sounds • Semantic encoding of meaning • Our brains process each type differently • Levels of Processing Theory says deeper levels of processing result in longer-lasting memories (i.e. semantic memory is best) • Paivio’s Dual Code Theory says that we remember best when we use both semantic and visual encoding.
What We Encode:Levels of Processing • Which type of encoding – visual, acoustic or semantic – helps us to remember best? • Craik and Tulving (1975) • Subjects forced to encode words in the three ways • Visually (is it capitalized?) • Acoustically (does it rhyme with…) • Semantically (Would it fit into the sentence?) • Found that semantic encoding yielded best recall! • Spend TIME learning and make MEANING out of what you wish to recall! • Self-Reference Effect: meaning that is personal – relate information to ourselves. Bransford and Johnson (1972) had subjects read the following paragraph: The procedure is actually quite simple. First you arrange things into different groups depending on their makeup. Of course, one pile may be sufficient depending on how much there is to do. If you have to go somewhere else due to lack of facilities that is the next step, otherwise you are pretty well set. It is important not to overdo any particular endeavor. That is, it is better to do too few things at once than too many. In the short run this may not seem important, but complications from doing too many can easily arise. A mistake can be expensive as well. The manipulation of the appropriate mechanisms should be self-explanatory, and we need not dwell on it here. At first the whole procedure will seem complicated. Soon, however, it will become just another facet of life. It is difficult to foresee any end to the necessity for this task in the immediate future, but then one never can tell. Without the context of “doing laundry,” subjects could not recall much!
Storage: Sensory Memory • If you can recall information, it must first be stored! • According to Atkinson and Shiffrin’ 3-step model, the first stop is sensory memory or the sensory registers. • Only holds an exact copy of sensory stimulus for a few fractions of a second. • More information enters our sensory memory than will get to STM • Sperling’s partial report technique illustrates the limitation of sensory memory. • When subjects were told to report ALL 9 letters flashed for a fraction of a second, they could not, but when subjects instructed to report 3 of the letters (one row of 3 letter row display of 9 total letters) they could do so with few errors • This proved that sensory memory could hold the information, but only very briefly
Storage: Sensory Memory • Sensory memory holds information just long enough to recognize and transfer it to STM for further processing • This happens through selective attention • Selective attention allows only a small percentage of sensory messages that bombard us to enter conscious awareness. • It is controlled not only by the focus of our attention but also the expectancies we have prior to exposure • Iconic sensory memories (icons) are visual representations that last only about a seconds in sensory memory • Echoic sensory memories (echoes) are auditory representations that may last for a few seconds (need a longer period to process language)
Storage: Short Term Memory • STM (working memory) is what is in your mind RIGHT NOW. • Information in STM only remains there for about 20-30 seconds • STM is very sensitive to interruption and interference • Brown, Peterson and Peterson (1959) measured the storage capacity of STM • Subjects presented with a stimulus and asked to immediately count backwards (rehearsal prevented) • By 20 seconds of backwards counting, the previously presented stimulus was forgotten
Storage: Short Term Memory • Unless information in STM is important/meaningful or is actively rehearsed, it quickly vanishes from STM and is displaced by whatever comes into our minds next • Displacement occurs, then, when new information enters STM and pushes old out • STM storage capacity is limited: the average adult can hold about 5-9 bits or chunks of information in STM • George Miller (1956) Magical Number Seven, plus or minus two
Storage: Short Term Memory • Remember the following number: 18122001198417891945
Storage: Short Term Memory • The number is 18122001198417891945 • Chunking • The process of organizing or grouping separate bits of information into larger units or chunks, can increase STM storage capacity. • e.g. 1812 2001 1984 1789 1945 (fits 7 +/- 2 rule now!) • Memory span is a measurement of STM capacity • It measures the largest number of items that can be recalled perfectly from STM after only one presentation • No study/rehearsal time is allowed • Sometimes used as a component of IQ tests • In STM, acoustic coding seems to dominate – especially for verbal information • Information in STM may be new or retrieved from LTM to be thought about and used.
Storage: Long Term Memory • LTM is our permanent storehouse for information • It includes all knowledge we have accumulated, all the skills we have learned, and all our memories of past experiences • The more meaningful the information, the more easily it can be stored in LTM • Unlike STM, LTM seems to have unlimited storage capacity
Storage: Long Term Memory • Information in LTM seems to be organized • New facts are learned by fitting them into a network of pre-existing knowledge • Propositional network theory • we store the smallest bits of meaningful information (propositions represented by circles or nodes) and create links (represented by arrows) to other nodes. • e.g. the proposition “dog” may be linked to the other nodes “bark,” “fur,” and “four legs.” DOG Fur Bark 4 Legs
LTM: Types • Two Broad Types of Memory Circuits • Declarative Memory includes facts such as names, dates, and events (sometimes referred to as explicit memory) • Can be rapidly learned and forgotten • Usually consciously accessed • Subdivisions • Semantic memory refers specifically to factual information • Episodic memory includes our personal or autobiographical experiences • Procedural Memory includes skills such as remembering how to ride a bike, play a musical instrument or eat with a fork (sometimes referred to as implicit memory) • Typically learned by repetition and practice • Difficult to unlearn • Often performed without conscious thought
LTM: Types • Eidetic imagery refers to visual LTMs • Eidetic memory is characterized by relatively long-lasting and detailed images of scenes that can be scanned as if the individual were physically present • Rare in adults – more frequent in children • Steven Wiltshire – eidetic memory • Flashbulb memories are remarkably vivid and seemingly permanent memories • typically of highly emotional and personal events in one's life • What makes the flashbulb memory special is the emotional arousal at the moment that the event was registered to the memory.
Biological Basis of Memory • Memories are not located in one part of the brain • Lashley (1950) tested this • created lesions in the brains of rats who had learned a maze. • Despite having damaged areas, memory was only weakened, not obliterated • Synaptic Changes and neurotransmitters • We already know that experience physically changes the brain • When learning takes place, more serotonin is released at certain synapses • This makes the neurons in this network more likely to fire, as sending neurons are more likely to fire and release neurotransmitters and receiving neurons seem to increase their receptor sites. • This process is called Long-Term Potentiation (LTP) • ACh also plays a role in memory; Alzheimers patients lack of
Biological Basis of Memory • Impact of LTP • Drugs that block LTP interfere with learning • Drugs that enhance it increase memory ability • LTP inhibiting drugs can actually erase recent learning • Memory enhancement? • CREB protein boosters may help trigger LTP • Neurotransmitter glutamate may also enhance LTP • ECT (electroconvulsive therapy) and head trauma may disrupt memory and learning as LTP in process is not completed
Biological Basis of Memory • Stress Hormones and Memory • When we are excited or stressed, we produce more hormones that make more glucose energy for the brain • This leads to increased activity in the amygdala in the limbic system, which is also involved in the formation of memories • Stronger emotions = stronger memories; weaker emotions = weaker memories • Helps to explain flashbulb memory • Hippocampus and explicit memories • Responsible for transferring STM to explicit LTM • Prolonged exposure to stress hormones can actually shrink the hippocampus and inhibit memory • Damage can disrupt movement of information to cortex (LTM) • Cerebellum processes implicit memories and classical conditioning (unconscious processes)
Retrieval: The Basis of Memory • Retrieval involves accessing information from LTM so that it can be used or examined in STM • Retrieval cues help us gain access to a memory • Methods of measuring retrieval: • Recall is when material must be remembered with few or no retrieval cues (free response test) • Recognition involves tasks loaded with retrieval cues; material must be remembered through identification (e.g. multiple choice test) • Relearning indicates the time saved when learning material for the second time (obviously, some learning was remembered) • Recognition is far easier than recall; we remember more than we can recall
Retrieval Cues • The more retrieval cues you have (like strings attached to whatever it is you wish to remember), the more likely you are to recall. • Priming • The activation of associations in memory – often unconscious. • Can shape our interpretation of events
Group 1: Unscramble the letters to make words: ocw nhe erohs ogd tca sfih eap tgoa Group 2: Unscramble the letters to make words: tluetec rortac neab rcon yecler ottmao eap cbocrlio Priming Demo
Retrieval Cues • Context can also serve as a retrieval cue • Sometimes referred to as locus dependent learning • Putting ourselves in the same environment we were in when we learned something may help us to later recall the learned information • Helps to explain déjà vu (literally meaning “already seen”) where similar contexts may trigger memories even when we are in new settings • Mood can also have an impact on memory • State-dependent memory says that we recall information learned in one state when we do so in that same state • e.g. learn information “high” – we may recall it better when “high” again! (of course sober-sober is BEST!!) • Mood-congruent memory says that we tend to recall experiences consistent with our current mood – good or bad • e.g. we recall how fabulous our childhood was when we are feeling happy, and how heinous it was when depressed
Retrieval: Serial Position Effect • People tend to recall the first items (primacy effect) and last items (recency effect) in a list • Demonstrates how short- and long-term memory work together • Primacy effect reflects long-term memory • Recency effect reflects short-term memory
Forgetting • While we may curse ourselves for forgetting things, it is good that we can get rid of useless information that would otherwise clutter out thoughts • In general we may experience encoding failure, storage decay, and retrieval failure • Encoding failure is when information is never really learned – it never makes the cut from STM to LTM • Storage decay happens when we do not use information in memory and it fades • Retrieval failure occurs when there are not enough retrieval cues available to prompt remembering • Consolidation failure occurs when disruptions prevent permanent memory from being formed
Forgetting: Encoding Failure • Because of selective attention, we only attend to very little of what we are exposed to • Unless there is effort, memories do not form • e.g. What does a penny look like?
Yaaa I forget so fast! Forgetting: Storage Decay • Even after encoding has occurred, sometimes we later forget things • Ebbinghaus researched this as well and the results of his experiments yielded the famous “forgetting curve”
Forgetting: Retrieval Failure • The information is there, but we cannot access it! • Tip-of-the-tongue phenomenon occurs when we are confident that we know the information but cannot retrieve it due to a lack of retrieval cues. Though we cannot recall it, we can often recognize it. • Interference occurs when some information may get in the way of your ability to retrieve other information • Proactive interference: inability to recall new information due to prior learning • Retroactive interference: inability to recall older information as a result of new learning • Sometimes, prior learning can facilitate the learning of new – e.g. knowing the rules of baseball may help in learning softball • Distractor studies?
Forgetting: Consolidation Failure • Memories new to long-term memory take time to be firmly implanted • Disruptions in this process can prevent permanent memory from being formed • Retrograde Amnesia – loss of memory for events occurring for periods prior to brain injury • Anterograde Amnesia – loss of memory for events that happen after brain injury • Infantile Amnesia – failure to consolidate information in memory before age 3, perhaps due to underdeveloped brain and limitations in comprehension
Motivated Forgetting • Sometimes we simply “forget” what happened – but why? • Many stages of memory processing – much can be lost along the way • Repression – a Freudian defense mechanism that pushes anxiety and guilt-arousing thoughts, feelings and memories out of conscious awareness • Many memory researchers believe that repression rarely, if ever, occurs – especially if the memory is emotional
Memory Construction • Gilbert (2006) “Information given after an event alters the memory of the event” • Implications? What you are asked and the way you are asked can lead you to remember the event differently! • Loftus’ research • “How fast were the cars going when they smashed into each other?” OR • “How fast were the cars going when they hit each other?” • The question determined the response, though all subjects saw the same video • Research on eyewitness testimony? • Misinformation Effect • When given incorrect information about an event, we tend to remember it incorrectly • Even imagining events that did not occur may create false memories • Suggesting something happened can make us believe it did when asked to recall later!
True or False? • Source Amnesia: attributing memory of an event (real or imagined) to an incorrect source; e.g. believing that you experienced something that you only heard about or saw on TV. • Reconstructive memory • Due to source amnesia and misinformation, we can have “false memories” we believe are true (“fill in gaps” when memory fails) • This is dangerous when we consider eyewitness testimony • Children’s underdeveloped frontal lobes make them more susceptible to false memories - accusation of child abuse? • Repressed/recovered memories of abuse? • Abuse happens – we do not want to dismiss legitimate accusations • Forgetting happens – especially concerning child abuse when kids may not comprehend what is happening • It is normal to recover memories, but when they are retrieved by therapist-aided techniques such as hypnosis of sedation, they are suspect • Infantile amnesia (pre-age 3) makes memories before this age unreliable
How to Improve Memory • Mnemonics are strategies you may use to improve memory • Mnemonists are people with extraordinary memory • Rehearsal: elaborative rehearsal is better than rote rehearsal! • Organization of material in meaningful ways • SQ3R – survey, question, read, recite, review • Overlearning • Metamemory – be aware of how memory works • Spaced practice – shorter sessions over an extended period of time – better than massed practice • Peg Word System – image + word you associate, then assign new material to each peg visually • Minimize interference • Maximize retrieval cues – state, location • Get enough sleep!
Thinking and Language Chapter 9
Thinking Cognition: all mental activities associated with thinking, including memory, knowing, communicating Cognitive psychologists study all of the following : Creating concepts Solving problems Making decisions Forming judgments
Concepts Yo I’m the prototype. • Mental category or label that represents a class or group of objects, people or events that share common characteristics or qualities. • Concepts help us organize our thinking • We organize concepts into category hierarchies (cars, cats, flowers, etc.) • Artificial concepts refer to those where each member of the concept has all of its defining properties while no non-member does, e.g. squares must have 4 corners and 4 right angles. • Natural Concepts have no set defining features but have characteristic features instead, e.g. birds where the object could be a chicken, sparrow or ostrich • Members of the concept have some characteristics of it • We compare possible members to prototypes, objects/events that typically represent the natural concept • Fuzzy concepts? • Concepts HELP but don’t provide all the answers Hi, I’m your dinner .
Problem Solving: Steps • Steps involved in problem solving: • Understanding the Problem • Planning a solution strategy • Carrying out the solution • Evaluating progress toward goal/results • Problem representation • the first step in problem solving – can help or hinder • how we frame or interpret the problem • We can approach problems visually, verbally, mathematically and concretely with objects; we may create a matrix to keep track of all possible combinations (LSATs, anyone?) • e.g. If we only see the problem of high national debt as a lack of tax revenue, we are limiting ourselves in coming up with other viable solutions to the problem that may be more effective – and more appealing – to the people.