Classical Conditioning and Operant Conditioning: Understanding Learning Processes - Prof. , Study notes of Psychology

Download Classical Conditioning and Operant Conditioning: Understanding Learning Processes - Prof. and more Study notes Psychology in PDF only on Docsity! 23/08/2011 22:23:00 8/23/11 Three Basics  Introspectionism  Behaviorism  Cognitive Psychology Introspectionism  First attempt to apply scientific method to thought (1880s). o Became systematic because of Wundt  First Cognitive psychologist  Titchener first American Student  Inspired by work in chemistry  Order and structure of periodic table  Goal: Description of the contents of consciousness; find irreducible “elements of consciousness.”  Method: introspection= to look at your own thought process. o Problem is:  Only covers conscious processing—“imageless thought” controversy  There really is some kinds of thought with no images  Poor reliability between subjects  People have different ideas of what is being acknowledged  Watching a mental process changes it  Watching yourself watch something changes what is occurring  Typical experiment: listen metronome o Try to observe and describe their thoughts as it was ticking Response: Behaviorism  1913, John Watson  Tenets he sets out: o Observables only o Theory must be parsimonious (simple) o Break behavior down into irreducible concepts.  Behaviorism took off during the 1910’s and dominated American psychology through the mid- 1950’s 8/25/11 Classical Conditioning  Basic Effect o If Unconditioned Stimulus  Unconditioned Response Then pair Conditioned stimulus with the unconditioned stimulus Then eventually Conditioned stimulus  conditioned response  Why is Pavlov famous? o Measurement  You can’t answer questions effectively without an experimental method  It’s not enough to say “she makes a face” (baby with pickle).  How many times must she eat pickles?  What if sometimes I offer pickled-shaped candy?  Can any stimulus be associated with a pickle?  Effectiveness o Food Aversion? o Associating a CS food (taco) with sickness caused by US x-ray causes a person to avoid taco because it is related to getting UR sick. o Tastes are easier to associate with nausea experience. o Visual stimuli are easier to learn with other things like shock. o Belongingness is observed in humans too. Fear conditioning to snakes/spiders vs. flowers/ mushrooms (dv=GSR)  What makes effective CS & US? o Novelty of CS or US o Bell alone, then bell  food  Bell associated w/ background  Bell associated w/ no food o Food alone, then bell  food  How does CC (Classical Conditioning) work? o Importance of one stimulus being conditional on another. o Learning that one stimulus is conditional on the other means that you’re learning about the environment o This implies that if one stimulus is not conditional on the other, you won’t get leaning o Prediction 1: If you present CS and US randomly, you shouldn’t get learning. o Prediction 2: Animals should ignore stimuli that don’t have predictive value.  A concept related to belongingness: instinctive drift (Breland & Breland.)  A natural instinctive behavior that’s related to what’s being taught.  Motivational State can also influence; a hungry animal does more food-seeking behaviors… o Quality, quantity, of reinforcer  Works as you would expect. o What else the animal might do  It’s not as simple as ‘the animal Maximizes good things, minimizes” bad things.  Even humans don’t do this, if the situation gets moderately complex.  Matching Law- When in situations of choice, people work to equalize ratios of work to reward.  The problem of definition o What is a reinforcer?  Thorndike called a reinforcer something “that brings about a satisfying state of affairs”.  The animal will work to achieve the reinforcer. o Another definition: physiological homeostasis  Animal seeks to lessen thirst, hunger, etc. Definition of reinforcement is based on biological drives.  Learning= a “stamping in” of the work that needs to be done to reduce hunger.  E.g., “I must not only consume and chew to get nourishment. I also must press the bar, and then chew.  Problems  Too many drives were proposed.  Animals (and people) do things that seem more likely to raise drives, not lower them.  If you watch someone and they do something that’s routine and then it is restricted. It becomes a positive reinforcer. o Bliss point is the point where the animal is when it is freely behaving.  Applications o Animal training  Revolutionized animal training.  Importance of temporal contingency  Exclusive use of positive reinforcement  Complexity of behaviors when these rules are followed. o Biofeedback  Operant conditioning of the autonomic nervous system.  For years, not explored because no one thought it could possibly work. o Apply operant conditioning principles to education 1. Make sure student doesn’t make mistakes; guide behavior 2. Immediate feedback 3. Review frequently.  Little enthusiasm. Teachers didn’t like it for their own reasons. Students were bored. o Token economies  Used in some mental health institutions, prisons and some classrooms.  Giving a reward (token) for positive responses. The token can therefore be exchanged for something at a “store”.  Said to be dehumanizing (mental patients) or because it seems that you’re “paying” students for behavior that they should want to do. 9/6/11 Turn to Cognitive Perspective  Problems with behaviorist accounts  Inspiration from outside psychology  Example of how to think about thinking A framework: scientific method Observe theorize testobserve etc. Prior to mid 19th century intro Introspectionism  First attempt to apply scientific method to thought (1880s) Introspection  Only covers conscious processing  Poor reliability between testing Turn to Behaviorism  Focus on observables only  Theory must be parsimonious “Observables only” in theory development was too restrictive. Overview of changes  Inability to account for all animal behavior indicated something might be wrong o Work from ethology--1 o Critical Period: A time when the animal is able to learn particular information rapidly and with little exposure; if the time window is missed, the animal learns with greater effort or not at all. o All about reinforcement o Critical Period in humans?  Johnson and Newport (1989)  A case for the critical period  Subjects  46 native Chinese or Korean learners of English  In the US for at least 5 years  Age of arrival: 3-39 years old  Method  Grammaticality Judgment Test  Results  Accuracy on grammaticality test correlated with age of arrival for subjects who arrived in US before puberty  Accuracy on grammaticality NOT correlated with age of arrival for subjects who arrived in US after puberty  Fixed action pattern—this is a complex behavior that emerges, full blown, with little opportunity  Fixed action patterns in humans?  Eyebrow flick  Coy o Catch eye o Look down  Inability to go from animal models to human behavior indicated it was incomplete  Posing abstract constructs suggested as what needed to solve these problems  Inspirations from other fields to use abstract constructs Skinner, 1957  The behaviorist account of language: Child utters sounds at random; is reinforced for utterances that are close to appropriate. Language is shaped. Chomsky, 1959  Naturalistic observation  Has the advantage of being “real”.  The key disadvantage is lack of control.  Case Studies  Only examining one person in great detail. They are often exceptional individual.  The advantage is that you may gain much richer insights by sustained study, rather than brief lab stints…but again, you don’t have much control, and the individual may not be representative of other people. o Relational – describe the world as you find it.  Rather than just observing one thing, you observe two things and see if they go together.  Correlation does not equal Causation  Musicians learn sequences better than non-musicians.  Musical training  improved sequence learning  Sequence learning skill musical training  But bear in mind that EVERY study you’ve ever seen concerning age, gender, race is a correlational study. Also many studies of things that you in theory could manipulate, but never would for ethical reasons (e.g., abortion, adoption) o Experimental-describe relationships  Allows you to make a claim about causality  You get that because the experimenter manipulates something.  Faces are special!!  Evolution has “prepared” us to perceive faces; we are a social species, etc.  But notice the problem… o Face/non-face is associated with identifying upside-down o EXPERTISE is associated with identifying upside-down.  To make this an experiment, CREATE experts.  Neuroscientific data o Localization-where is a cognitive function located in the brain?  Method 1: Brain damaged patient: identify the patient’s problem, and identify where the damage is. (E.g., aphasic patient from last class)  Method 2: Brain-intact subject: observe activation using functional MRO or PET while the patient does a particular cognitive task.  For each technique there’s the brain side and the behavior side.  For activation studies  Speech production  Patterns of activation associated with a target cognitive process o The problem: anything  Four techniques  Clues about architecture o Diversity where there could be unity. o Unity where there could be diversity. 9/13/11  Four techniques by which localization data can be brought to bear Clues about architecture o Diversity where there could be unity. o Unity where there could be diversity  Direct observation of a behavioral construct: Evidence as to what cells code interpreted as observation of a construct, e.g., lines or timing. o Central Nervous system o Gross anatomic stricture o Nucleus, Cortical sub-region  Brain informs cognitive theory o Competing cognitive theories make different predictions about neural basis of a task and we know enough about the brain to collect discriminative data.  Confirm a behavioral construct o This the biggest source of confusion for people who are not used to thinking about neuroscience o Images associated with a construct are taken as proof of the psychological reality of the construct. But you will find some locus of ANYTHING. o Theory of space including a special module for parallel parking o The theoretical value of a cognitive construct like “scan in STM” is established through behavioral experiments. It’s a dependent measure  We can show that the relationship between the construct (scan) ad behavior (tasks)  We can show that the construct really is a cognitive primitive (and different than the parallel parking module). Low-Level Vision  Problem: the input is impoverished o You have lots and lots of information but the individual bits of information not useful for you  Simple Computation How do you get from one to the other.  Researches divide this question into two parts:  Low-level vision: we assume that we can’t get much information out of this array of intensity values. There must be algorithms that summarize this into.  High-level vision: taking the output of the low-level processes and transforming it to get objects and their properties. Crucial summary –find edges  Edge is a sudden discontinuity in intensity  Edges frequently correspond to the boundaries of objects; a map of edges is a good start to identifying objects.  Edges are invariant to lighting conditions  Computationally easy to find discontinuities o Comapre means of adjacent columns, rows, diagonals Textures  Assess at more than one scale  Assess neighboring columns: yields five edges  Assess every three columns (i.e., take the mean) yields one edge Biological Evidence  It does seem hat some cells relatively early in the visual processing stream care about edges and lines. Now how do you get distance, shapes, etc?  Many of the qualities of objects that we would like to know about trade off with other qualities. (This is the second “problem to be solved.”) o Shape/orientation o Reflectance/light source/shadow o Size/Distance  Isn’t it the case that we frequently just know the size an object should be?  This is familiar size  Cues to distance  Convergence—not very effective o The Parsing Paradox  If perceptual organization is a matter of mapping sensations onto structural schema, which happens first: interpreting the whole or interpreting the parts? How can someone recognize a face until he has first recognized the eyes, nose, mouth and ears? Then again, how can you recognize the parts until you know that they are part of a face? o  Navigation vs. Object identification  There is pretty good evidence that spatial information that helps us get around is independent of the information that helps us identify objects.  What where theory of visual processing  Mishkin & Ungerliedger  What How theory  Figuring out spatial information to see how to reach for an object  Goodale & Milner o Some evidence from brain damaged patients that this separation o Of action and object identification applies to humans as well 9/22/11  Attention- Whats it for? o enhances processing, so you must know when you are attending to the wrong thing o you can switch between two tasks or develop automaticity to evade the limitation of attention o attention is necessary for even the most basic process- visual processing  limited- not all sensory stimuli simultaneously get continues processing  selective- attention must be selective exactly because it is limited; decide where your attention needs to be directed  a consequence of selectivity: sometimes you’re attending to the wrong thing  how do you know that you’re attending to the wrong thing? o Things that catch your attention: o unexpected physical stimuli o your name o start with environmental stimuli processing physical characteristics (ex. Loudness, pitch) processing semantics (meaning, category membership) Awareness  cocktail party phenomenon- if you can pick out your name in a crowded room while you’re focused on your own conversation, then you are monitoring all other conversations in the room  Filters! o early filter- only process physical stimulus of conversations you aren’t paying attention to; ex. if it is really loud o late filter- everything is processed for its physical and semantic characteristic; everything around me is being processed not just for how loud it is but also for what it means  Method to study early vs late o headphones put on a person and two different things are played in each headphone and they told them to pay attention to only one of the stories in one ear- made them repeat to make sure they are paying attention (shadowing) o they were getting physical characteristics but barely any semantics o people don’t remember words from unshadowed ear o people don’t notice if speech is played backwards, or if language changes o people do notice if a pure tone is played, or if there is a gap, or if the gender changes o conclusion: early filter  why early? Everything including unattended ear, is processed for physical characteristic  Early Filter? o cocktail party phenomenon- 2/3 of the time people kept shadowing even when their name has been said  More late filter evidence (1960) o same experiment o people would pick a couple of words from the unattended ear- none noticed this (ex. If they mix baking and music they switch instruments and ingredients- they were paying attention to semantics!)  Indirect Measures- Corteen and Wood 1974- Phase 1 o Phase 1: shock associated with three city names (ex. Dallas, freson, new york) [classical conditioning]; Train until GSR response (palms sweet- measure of autonomic nervous system activity) o Phase 2: Dichotic listening: they shadow an irrelevant message from one ear. The other ear gets words, plus occasional city names. Do they show GSR to the city names? o participants showed GSR response 38% of the time to the old city names, 23% of the time to new city names o Early filter looks right—(note Goldstein kind of waffles on this) o in the studies where people seem to get semantic info, it looks likely that they are actually rapidly switching attention to the ear they are supposed to be ignoring. When you do the experiments more carefully to guard against this, it looks like they don’t get much info from the unattended ear. o we can process everything on physical characteristics but not on semantics ← ← Cognitive load  People want to attend to both channels. But they cant. Its too create a cognitive load. How do you deal with that?  1. Switch between two tasks  develop automaticity for one or both o you’ve developed the ability to do the task with very little attention o automatic vs. controlled tasks  automatic- little or no attentional cost, with or without intention, not affected by motivation, can happen with out awareness Intro to Cognition 2150 Capacity 20 items 7 items Unlimited Duration 1 sec 30 sec Forever Code Physical Aud/Vis/ Semantic Aud/Vis/Sem Purpose ??? Brief Storage Permanent Storage Forgetting Decay, masking Decay, inference ??? o Early Span of Apprehension Studies  Background: introspectionists were interested in how much information could be in consciousness at one time o Span of Apprehension  Work like this continued in the early part of the century; span estimates were always the same, but there was a nagging feeling that something was missing from these experiments. o Can also lose via masking o Properties of Iconic Memory  Large Capacity—can be pretty accurate on arrays up to 20 characters  Physical properties; probably little semantic  Lost through decay or masking  Decay actually starts when the stimulus first appears: decay doesn’t start when the stimulus disappears.  You might think it is sustained activation of representations, but it is probably sustained activation of processes. Short term memory---model #1  Much of what we have described as Short term memory was actually inspired bu another model, Working Memory. Working memory---model #2  Phonological Loop o Her phonological loop has two components o The phonological store stores about two seconds worth of aufitory information. o Information can enter the phonological store from the environment. o Information can also be entered into the phonological store via the articulatory control process  Prediction o Since the store lasts 2 seconds, people who can talk fast have larger capacity o Since the store lasts 2 seconds, anyone has small capacity for long words. o Since the store is auditory, you should confuse words that sound alike (cap, cat, can) o If you busy the articulators (blah blah blah) the articulatory control process can’t put anything on the phonological store, so you’re forced to code the words some other way: lo and behold these effects disappear.  Primary memory—representation o Release from proactive interference. o This result indicates there is also a semantic code in primary memory  Visuo-spatial sketchpad o This is where you store visual or spatial information. It is similar to mental imagery, which we’ll discuss later.  Central Executive o Cognitive supervisor  What is working memory for? o Not just maintaining some information briefly… o Size of vocabulary correlates about .4 or better with non-word repetition (loddernaypish) 10/4/11 Memory—Encoding Intro to Cognition 2150 Memory: The Basic Problems  Getting it in o How are memories creates? Encoding  Keeping it in o How are memories stored and retained? Storage  Using It o How are memories accessed and used? Retrieval Which Factors determine what gets into long term memory?  Imagery o You get a big boost of memory with mental imagery  Emotion o Things that engender some emotion will be remembered later on. o It may not be the emotionality of the object, but some other property—e.g., guns attract attention because they are most likely to be “active” in a scene; emotional scenes may be distinctive. o Another approach: Use exactly the same stimuli, but put the person in a good or bad mood.  But this is a different idea—you’re not remembering happy or sad stimuli o Another approach: stimulus materials are identical, but in one case they elicit emotion, and in another case the same stimuli don’t elicit emotion. o Flashbulb memory  Original study by Brown & Kulik asked people about their memory of the Kennedy assassination.  Repetition alone o Sheer repetition does NOT necessarily lead to memory for the stimulus  Thinking about meaning (depth) o “Depth” refers to thinking about meaning, and how the to-be-remembered material relates to things that you already know. Shallow processing means thinking about physical characteristics of the stimulus. o Note  It is not the case that deep processing leads to better memory because it is harder; other experiments have checked for that.  Effort/Desire to learn o Intention or effort is irrelevant o Effort to learn—Hyde & Jenkins (1973)  Deep=rate pleasantness  Shallow= does a word contain a “Q” or an “A”?  Depth has a big effect while intent doesn’t matter. Limitations of Levels of Processing 1. Definition of levels and circularity (note that this is a problem with the theory, not the data). 2. We can’t ignore what’s happening at retrieval. Transfer-appropriate processing  Does deep encoding always lead to better memory? Morris, Bransford & Franks (1977) o Deep encoding is better than shallow encoding when coming to recognition. o Shallow encoding is better deep encoding is better when it comes to rhyming.  Transfer appropriate processing : when processes are the same at encoding and retrieval, then memory will be successful; when the processes are different at encoding and retrieval, then memory will not be successful. (Note that this is another powerful idea that is dangerously circular.) What happens after encoding?  The memory does NOT simply sit quietly, waiting to be recalled.  Evidence from retrograde amnesia o Anterograde: Old memories mostly intact| Can’t encode new memories o Retrograde: Old memories lost| New memories encoded normally  Retrograde amnesia: temporal gradient Intro to Cognition 2150 o Not all memories from the past are equally affected: recent memories very, affected distant not so much.  Example: Blow to the head… Interpretation  Initially, memories are fragile  Memories must be consolidated after they are encoded  Consolidation is the process by which they become more stable, even if they are not practiced.  It takes years for a memory to be fully consolidated. 10/6/11 Memory Retrieval Free Recall  Very minimal information from the experimenter: experimenter simply says “Remember” and the context is usually implied, occasionally described. Cued Recall  Experimenter also gives part of the information, or some related information. Recognition  The to-be remembered information is presented, along with other stuff (distracters) and the subject must distinguish new from old. Savings in relearning  Subject learns some material to a criterion, and the # of trials required is noted. Later subject relearns the material to the same criterion; if fewer trials are required, that is savings. Difficulty  An important principle is this: whether or not it appears that someone remembers some material depends Measures difficulty  In general, free recall is hardest, and then cued recall, then recognition. Shepard & Recognition  Subjects see 512 words, then take a 2-chice recognition test—get 88%  Subjects see 612 brief sentences (e.g., “The truck swerved to avoid the limping deer), then tae 2- choice recognition test-get 88%  Final experiment Caveat  Although it is true that recognition memory is usually very good, you have to bear in mind that the difficulty of a recognition test is the distactors. Hart 1965, 1967  When free recall fails, subjects recognize answer 50% of the time o Recognition more sensitive than free recall Tulving & Pearlstone, 1966  Condition 1: Free recall, then cued recall  Condition 2: Cued recall, then cued recall  Cued recall50% more remembered than free o Cued more sensitive than free recall Nelson, 1978  When recognition fails, subjects relearn the material faster than new material o Savings more sensitive than recognition Why the difference in sensitivity?  It feels like memory success is some combination of memory strength and the sensitivity of the test.  Tests are sensitive to the extent that they give you good cues.  Free recall: context (time and place)  Cued recall: context + partial information  Recognition: context + all information Mnemonics  General o Method of loci o Pegword  Specific Intro to Cognition 2150  Amnesics show a normal forgetting curve o Poor retrieval  Can’t retrieve new things but they can retrieve things that happened before they got amnesia o People give up- researchers gave up on the idea that there is a single memory system, which is missing some process, leading to the pattern of spared and impaired memory functions  You have 2 types of memory  Explicit- you are always aware of explicit memory o Conscious memory, tested directly, accompanied by awareness that you’re remembering something  Implicit o Revealed by indirect testing, just perform a task; memory shown by performance. Motor skill priming  People give up again- researchers gave up on the idea that there are two memory systems, implicit and explicit, largely due to separability in the brain  Memory Systems  Declarative memory- episodic/semantic o Episodic- have that flavor of “it happened to me”; specific time and place o Semantic memory  Motor skill- pursuit rotor, mirror tracing  Repetition priming- gollin figures (like the elephant), stem completion etc.  Skeletal conditioning- classical conditioning w/a motor response as the CR o Puff of air on the eye conditioning so that a tone is associated with a puff to the eye  Emotional conditioning- classical conditioning with an emotional response as the CR o Boat horn = anxiety; you condition a picture to give you anxiety  Very important source of evidence for separability is the brain basis of these types of learning o Declarative memory  Repetition priming- Hippocampus?  Motor skill learning- basal ganglia  Skeletal conditioning- cerebellum  Emotional conditioning- amygdala  Multiple memory systems o This research has expanded our notion of memory. There appear to be multiple cognitive systems in the brain that have some plasticity  What about people with ordinary memories?  Memory w/out awareness o Priming  Flash words on screen at fastest time that yields 50% correct  Read list of words  Filler task to delay to try and make them not realize that the next list of words don’t contain any of the previous words  Lexical decision test o Memory with out awareness: memory skill  Show them a sequence of lights but they don’t realize the sequence and they get faster and faster but if you change the sequence, they get slower again  They usually don’t realize the sequence o Memory with out awareness: skeletal conditioning  Show subjects a silent movie; tone and puff to the eye o Memory without awareness: emotional conditioning  Familiarity o What’s happening when something feels familiar, but you can’t place why?  One source: priming leads to easy processing o False fame effect Intro to Cognition 2150  Task 1- read list of novel names (ex. Sebasian weisdorf)  Task 2- tell me who is famous in this list ; Horatio Sanz, Sebastian Weisdorf, Morgan Fairchild  People will think that Sebastian is famous because they were primed to his name around an hour ago  If task 2 is immediate: no false fame but after 24 hours, false fame works  Process purity o We just saw that an implicit memory (priming) can influence an explicit task o Could an explicit memory influence a priming task? o Phobias: you see a snake and explicit memory says its harmless but the emotional conditioning is telling you to run o Motor skill: 10/18/11 What’s in memory?—concepts The Importance of concepts  What’s this?  How do you know they are cherries, given that you’ve never seen them before?  Does it have seeds inside?  Does it have lungs? Definitional View  A concept is a list of necessary and sufficient features. E.g. to be classified as a grandmother, you must: o Be female o Be a parent of a parent  Thus, by the definitional view concepts are definitions. o This idea works okay for some terms (e.g. kinship or legal) but poorly for most others. o E.g. what are the necessary and sufficient conditions for being a pear?  Data like this were taken to mean that the definitional view is wrong.  If the definitional view  How you reason o Robins like to eat onions  Do you think starlings like to eat onions? o Owls like to eat onions  Do you think starlings like to eat onions? o Robins are seen to be more bird like therefore starlings are more likely to eat onions. Owls are strange birds and therefore eating onions might just be another weird things about them. o More than just typicality—levels  Basic level categories: most inclusive but members still share most of their features. E.g., most “birds” are “winged”, lay eggs  Basic level categories are argued to be psychologically privileged, meaning that’s what we usually use when thinking.  Note that basic level depends on expertise. If you’re an expert, what is a subordinate level for everyone else may be a basic level for you.  Superordinate level category is one level more abstract (more general). E.g., “animals” do not all share features: some are “winged” some are not; some are “tailed” some are not; some are “warm-blooded” some are not, etc.  Subordinate level categories are less abstract (most specific) than basic level. E.g., “wrens” are all very similar; only a few features Probabilistic/Similarity Models  An influential answer has been “probabilistic, or similarity models.” o Called probabilistic, because category membership is a matter of probability, not all-or none. Similarity, because the likelihood of being a member of a category is calculated by computing the similarity of the exemplar to the category.  Prototype model o Create a deck of cards with exemplars of A’s and B’s (but not prototypes). Intro to Cognition 2150 o Study exemplars until can categories correctly o One week later, categorization test for old, new, and prototype. o How a prototype model works  When you see a new exemplar you compare it to the prototype; the more similar it is to the prototype, the more confident you are that it belongs to that category.  Thus, when you see the prototype dot pattern, you’re very confident that you know its category. o It almost feels like the prototype model has to be right o Problem:  Not that these effects all depends on your having a prototype of each category stored in memory.  Exemplar Model o Exemplar model also accounts for the fact that you can recognize specific dogs, not just the prototypical dog.  Problems o Feature selection: Compare Barack Obama & a pack of Double Mint  Similarities can be chosen by using certain questions (weighs less than six tons, sometimes described as “sweet”.  However if certain questions or features are picked you can find out different things. (respiration, wears a hat) o How you judge similarity depends on what else is around or the context  Categorization based on rules  Similarity o “Take an object that is 3 inches in diameter: is it more similar to a pizza, or to a Quarter? o Most people say “quarter”  Categorization o The object is 3 inches in diameter. Is it a pizza or a quarter? o Most people say pizza. o Low similarity, high diagnosticity  Allen & Brooks o Subjects trained to categorize diggers vs. builders. Some told to memorize exemplars learn the categories that way. Others told to categorize using a rule. At test they see creatures that follow the rule to define them as one creatures, but they are most similar to the other creature. o Results  When confronted with builders who were similar to diggers, subjects’ categorization depended on the instructions they had received:  Told to memorize: categorized based on similarity  Told the rule: cat The return of rules 10/20/11 EXAM NEXT THURSDAY Watch House Paternity Episode Memory---how is it organized? Properties of Memory  Property 1: Quantity and Speed o You can pluck answers out of memory rather rapidly  Property 2: Neat Miss o Names that are similar or somehow related  Property 3: Relevant Info o Does a canary have lungs? o You know the answer despite not being tested on it or  Property 4: Resistant to faulty input Intro to Cognition 2150 EXAM 11/1/11 Visual Imagery What is it? Imagery  Most people report “looking” at a mental picture to answer such questions.  This implies (but doesn’t prove) that there is a type of representation that is quasi-pictorial, that is, has some properties of a picture. Analog vs. proposition: “A ball is on a box”  Proposition  Relation  Syntax (there is a proper way to form a proposition)  Truth value  Abstract  Non spatial  Image (Analog)  No distinct relation  No syntax  Truth value only when described  Concrete  Spatial Medium How do we know there are images?  When you read all of it gets transferred into proposition.  The big controversy came if it was just proposition or position AND images.  Property 1: Rotation  Property 2: Size Zooming  Property 3: Scanning o Stronger linear relationship between how long it takes you to scan and distance scanned  Property 4: Brain locus What is imagery like? Memory representationsPerceptual processes Memory representationsvisual experience “screen”early perceptual processes Confusability (Perky, 1910)  People confused imagery and perception Like perception: Interference  Atwood, 1971  High imagery: “A nudist devouring a bird”  Low imagery: “The intellect of Einstein was a miracle”  Visual interfering task: subjects see a 1 or 2 on a computer screen & must say which digit did not appear.  Auditory interfering task: subjects hear a “1” or “2” and must say the other digit.  Control group: no task  Visual interfering task: big effect on high imagery pairs  Auditory interfering task: big effect on low imagery pairs Like perception: separation of “what” and “where”  Visual imagery: o Color questions (what color is the outside of a pineapple) o Size comparisons (which is bigger a popsicle or a pack of cigarettes)  Spatial Imagery o Letter rotation o Mental scanning  Damage to ventral impairs visual imagery. Damage to dorsal impairs spacial imagery.  Imagery not like perceptions: distortions o Which city is further North, Rome or Philadelphia?  Imagery not like perception Intro to Cognition 2150  Image Inspection o Images What is imagery for?  Memory o People are better at remembering concrete nouns than abstract nouns o It is also harder to create an image for abstract nouns than concrete nouns o Does bizarreness help?  It seems to; data conflict a bit from study to study.  Make implicit knowledge conscious o Is the writing on the Coca-Cola logo cursive? o Which is closer to the ground, the tip of a horse’ tail, or the knee on its back leg? o Which is larger, a tennis ball, or the rounded part of a light bulb.  Prepare for future actions 11/3/11 Language Ambiguities of Language (what makes it hard)  The Problems o How do we perceive speech sounds (phonemes)?  Phonemes are basic speech sounds.  You can get different phonemes within a language.  Why is phoneme perception hard?  Phonemes produced fast (50/sec)  Different speakers produce differently (accents based on where you grow up)  A single speaker produces them differently. Depending on the context of the phoneme—this is coarticulation.  Does sometimes go wrong—famously when trying to understand son lyrics. o How do we perceive words?  Why is it hard to understand words?  Speech stream: no space between o How do we perceive sentences?  Why are sentences hard?  Obviously word order is crucial: o “Jane kissed Jon” o Jon kissed Jane”  Even if the word order is the same the meaning of the sentence can have different interpretations. o How do we perceive texts?  What makes understanding texts hard?  A text is a collection of sentences forming a paragraph or a collection related paragraphs  Language is full of gaps and full of holes. How the ambiguities are resolved  Solving Problems o Perception of phonemes  Phoneme restoration effect: when a phoneme is missing or ambiguous there some process where the phoneme is still perceived.  McGurk effect: we use visual information as well as audio information. Hearing one thing and seeing the mouth form to make a different sound.  Categorical Perception: Our perceptional system disregards slight differences in phonemes. o Perception of words  Most researchers think it’s a matching process between input and the lexicon.  To test lexical access, you can do cross-modal priming. Intro to Cognition 2150  Gaskell et al (1998) showed that mispronounced words do get lexical access if they are mispronounced the way people tend to mispronounce them.  Reading  Visual input goes either to: o Spelling o Sound pattern 11/8/11  How are sentences parsed? o Grammar refers to a set of rules that describe o Incorrect Theory  Grammatical sentences are constructed word by word, by selecting the next word in a sentence based on the associations of the rest of the words in the sentence. o Word Chain Grammars  Perhaps just specify next part of speech, not specific word.  “The boy took his baseball bat and hit the ______” could be completed by a noun (ball) but the next word could also be an adjective (smelly ball) or an adverb (swiftly escaping boy).  The reason that word chain grammars don’t work….  Dependencies o E.g., verbs must agree, “either” implies “or”; “at” implies a noun  Embeddedness o Dependencies can be embedded o “Either Dan or Brian will go” and then embed that clause in another clause, forming “Either Dan or Brian will go, or Karen and Jon will go” o Because embedding opportunities are infinite, you’d need an infinite word chain generator.  The Solution—phrase structure grammars o Phrase structure grammars use hierarchical organization, not linear (as word chains did) o Phrase structures specifies a limited number of sentence parts and a limited number of ways the parts can be combined.  Sentence= noun phrase + verb phrase  How do we get embeddedness? o Embedding is accounted for because definitions can be recursive, meaning a definition has that definition embedded in it. o Key Question  What cues does the parser use to decide which phrase structures are which?  Key Words o “a” indicates that a noun phrase follows “who,” “which” and “that” indicate a relative clause o Fodor and Garrett (1967)  The car and the man whom the dog but drove crashed  The car the man the dog bit drove crashed  Word Order o Parser assumes that sentences will be active (noun, then verb, then direct object)  Principal of minimal attachment o If new word can be attached to an existing node in a phrase structure, go with that interpretation.  Phrase structures – ambiguity  Phrase structures can account for (some) ambiguities of language. Some sentences are ambiguous: “They are frying chickens.” Intro to Cognition 2150 o Working backwards  As the name suggests, working backwards means imagining being at the goal of the problem space and seeing If you can figure out a way to get to the initial state, or closer to it. o Means ends analysis  Compare the current state to the goal state. If there is not a difference between them, the problem is solved.  If there is a difference between the current state and the goal state, set a goal to solve that difference. If there is more than one difference, set as a goal to solve the largest difference.  Select an operator that will solve the difference identified in step 2. 11/15/11 Prior knowledge can also impede.  Functional fixedness o People fixate on the typical function of an object so they fail to use it in a way different to the way they are used to. o Depends on if you have prior knowledge o You can be fixated not only on the function of an object, but also on the procedures used to solve the problem—try to solve the problem as you have been Reasoning As psychologist study it, reasoning usually refers to problems that are amenable to formal logic in the form of deductive reasoning. Deduction vs. Induction  Induction: strart with specific case(s) and ask what general rule you can abstract. Tells you what is more probably true.  Deduction: start with a general assertion  Are people logical?  Isn’t logic just formalizing the rules of everyday thought?  If that’s the case, then errors are just result of misreading, carelessness, etc.  BUT errors happen all the time, and are systematic Deductive logic: 2 premises & a conclusion  Premise: If Dan can jump well, he can dunk a basketball  Premise: Dan can jump well  Conclusion: Dan can dunk a basketball Case-based reasoning  Perhaps we are merely good at scenarios with which we are familiar.  But case-based reasoning can’t be the whole story because people are good at unfamiliar problems too. Message: familiarity is not enough to explain why people are good or bad at these reasoning problems. Pragmatic Reasoning schemas  These are bundles of “if-then” rules which are activated for situations like permissions, obligations, or causations. o Rule 1: If the action is to be taken, then the precondition must be satisfied. o Rule 2: If the action is not to be taken, then the precondition need not be satisfied. o Rule 3: If the precondition is satisfied, then the action may be taken. o Rule 4: If the precondition is not satisfied, then the action must not be taken.  The emphasis is on the fact that they are pragmatic, meaning useful; formal logic leads to conclusions that are correct, but not very useful, e.g., “If I have a headache, then I take an aspirin” leads to conclusion “If I have not taken an aspirin, I must not have a headache.” Evolutionary View  We are social animals, and we evolved to do social exchange. Part of doing social exchange is the ability to catch cheaters. Bottom Line  People are not logic machines who can plug any problem into a logical formula Intro to Cognition 2150  The familiarity of a problem doesn’t matter much  We still don’t have a complete answer re: the critical features of a problem that lead to successful reasoning; pragmatic reasoning schemas & evolutionary perspective are two viable tries at a theory. Induction  Analogy o Analogical reasoning is a type of inductive reasoning o You extend knowledge from a situation you do understand (source) to one that is less well understood (target). o Good analogies share characters AND their important relations o Analogy is used  Teaching  Literature (simile and metaphor)  Learning  Persuasion o But analogy is inductive  Not all properties and relations follow o Steps using analogy (Ideally, structural similarity)  Retrieval of source  Map new situation to source  Extension—use source and mapping o We are very susceptible that analogies are a good way to reason. o Retrieval of source is hard, but mapping is usually easy.  Source retrieval is usually prompted by surface similarity, but a good analogy needs structural similarity for mapping.  This is why people like to prompt analogies for you. 11/17/11 Decision Making Definition: two or more choices laid out, and you must select one Question: What, if any, are the consistent rules that guide such decisions? Summary if main point:  People’s reasoning is not driven by optimality.  People’s reasoning is driven by heuristics. Rational Theory: refers to being internally consistent e.g., transitivity should hold  A or B? pick A  B or C? pick B  A or C  shoul pick A Normative Theory: theory is prescriptive, values some choices over others.  A or B?  should pick A  Example of a normative theory o E.g., expected value theory—get the highest expected value o Probability obtain x value  Expected utility theory—value of outcomes vary depending on the individual (probability if win)X(value of prize) Irrationality  Effects of how you measure preference  Effects of problem description Examples of Problem Description  Irrationality Framing  Sunk Cost o A sunk cost is time, money, or other investment that is irretrievable spent, and therefore should not affect current decision making, and yet does.  People do not always behave rationally Heuristics  A heuristic is  Representativeness o Used when you are asked to judge the probability of an event. Intro to Cognition 2150  Availability o Used to judge the probability of an event.  Anchoring and adjustment o to use it, you do a quick estimate based on memory, or on information provided in the problem, and then adjust the estimate  Simulation o Downhill—adding a high-probability event to the mental simulation so that the outcome would have been different o Horizontal—trading equal probability o Uphill— Information We ignore  Sample Size o Sample size refers to the number of things in a group that we are evaluating.  Base Rate 11/22/11 Intelligence  What is intelligence? o J. Of Ed Psych poll in 1921  Capacity to learn from experience  Ability to adapt to surrounding environment o In 1986 same as above and includes:  Includes metacognitive processes to govern cognition  May vary by culture  History if intelligence testing o Measures of intelligence  The study of intelligence really got going in psychology labs o Two traditions of intelligence measurement  Psychophysical abilities  Sensory acuity, physical strength, motor coordination  Sir Francis Galton (1883): o “Those equipped with the best sensory abilities, for it is through the senses that one come s to know the world.” o Many distinct abilities  Judgmental abilities  Problem solving and reasoning  Alfred Binet (1890) o His goal was to classify children, not measure absolutely; he cared about predicting school performance, not characterizing the person. o Compare 7-year old to other 7-year olds. o Stern (1912) suggested comparing a ratio of chronological age to mental age: IQ = (MA/CA)x100  But problems came around the age of 16 where the mental age stopped increasing. o Standard tests  Wechsler Adult Intelligence Scale (WAIS)  Verbal (vocab, verbal similarities)  Performance (picture completion, picture arrangement)  The Ravens Progressive Matrices Test  Factor Analytic view o To the statistical technique to see which type of intelligence testing is correct o We then take a sample and see how many types of intelligence there are  We give various tests (such as vocab, grammar, etc.)  If these represent separate abilities Intro to Cognition 2150 Much more questionable  Animals ability to understand “self” o Some of your cognitive abilities involve understanding that you are separate from other individuals o Mirror Studies  Chimps will stare at the mirror, look behind it, display in front of it, etc. Some have used it to see previously unseen parts of the body, e.g., inside of the mouth.  Caveats  The numbers of chimps in individual studies who respond to the mirror vary widely.  Upshot  What we really care about the sense of self and not the recognition of self.  Prosopagnosics can’t recognize self in mirror but have sense of self.  It is possible that sense of self is actually secondary to sense of others.  Sense of others—theory of mind  A term coin  Animals ability to intentionally deceive others o Sense of others—theory of mind  Deception studies are used to investigate theory of mind.  Plovers will fake an injury display o Intentions in chimps  Premack had one of his star chimps (Sarah) watch video tapes of humans engaged in problem solving o We might be the only species to have theory of mind. 12/6/11 Applied Cognitive Psychology Education and Product Usability  Education o The Problem  The difficulty is that most things can only be controlled in the laboratory. The conditions that need to be studied are found in the class room o Solution  Do studies in classroom  Find cognitive principles that are SO universal, they always apply. o Humans are not very good at thinking and tend to avoid it.  Humans are not very good at thinking compared to other things our mind does.  Humans are really good at seeing and moving—Machines are not  Thinking is slow, effortful, and unreliable.  Most of the time, we don’t reason, we rely on memory.  Not just facts but procedures.  Memory is much more like vision and movement. It is fast, effortless, and relatively reliable. o People are naturally curious, but curiosity is fragile—we think only when we believe that thought will be successful  Problem solving brings pleasure  Environment in order get people to like it  Surprise them  Change mode of presentation  There is too much variation in individual interest for it o work well  Content o Using this fact to make school more interesting  Object Usability o If possible simplify o Visibility of current state of object and what are the options Intro to Cognition 2150 o When in doubt, subsidize it.