Unit 2 Cognitive Psychology PDF

KMF 1014 Introduction to Cognitive Science  Cognitio (Latin) – to acquire knowledge through the exercise of mental powers (i.e. the mental process of knowing)  All processes by which sensory input is:  Transformed  Reduced how we receive  Elabo...

KMF 1014 Introduction to Cognitive Science  Cognitio (Latin) – to acquire knowledge through the exercise of mental powers (i.e. the mental process of knowing)  All processes by which sensory input is:  Transformed  Reduced how we receive  Elaborated information from the  Stored outside world through  Recovered our senses, how we  Used organize it and use it.  Introspection – to understand what goes on in the MIND  How we think  How we think about thinking Cognitive psychologists seek explanations for all functions introspection suggests our MIND carry out Cognitive Architecture in support of the functions?  Reasoning Language Perception Learning Imagery Problem Solving Mind Memory  Sensation Visual Auditory Obtain Perception Perceptual Illusions Attention Information Processing Memory Store Statement about Representations the world Concept Proposition Single entity or group of entities Rules Analogy Utilize Day-to-day Comparison Specify relationships between similar between proposition situations  Emphasis on the study of internal mental operations  Computer as a metaphor for MIND  Mental functioning = representation & computation ▪ Cognitive Architecture  Two tasks of Cognitive Psychologists:  Developing theoretical framework to explain the workings of the brain  Devising experiments whose results serve to illuminate that framework  Knowing ‘how’ Knowing ‘what’ General knowledge automatized about concepts abstracted from scripts experience concepts Definite time/place located in personal histories propositions schemata  Trying to look for something that you have misplaced  What did you do in order to search for it?  What were your thought processes during this search?  Trying to recall the name of a person you used to know  What did you do in order to recall that person’s name?  What were your thought processes during your recall attempt?  Concepts Have notions or ideas of what things are  An idea about something that provides a means of understanding the world (i.e. mental representation)  Often single concept may be captured in a single word  Each concept relates to other concept  Derived from specific instances  The mark of having mastered a concept is the ability to categorize objects or events of a domain  Coherence (kepaduan)  Category =A set of objects Seafood? that ‘belong’ together (i.e. coherence)  A class of similar things  Enables prediction  A concept that functions to organize or point out aspects of equivalence among other concepts  Based on common features or similarity to a prototype Category – Food (Protein) Concept Category Different kinds of fish  Concepts and categories are central to how humans represent knowledge about the world  A concept is a mental representation of a category ▪ Form concept from categorization  A category is a set of objects that ‘belong’ together ▪ Each member of the category is a concept  A basic crucial process that allows us to organize our experience of the world so that we can function in it  Good vs bad  Safe vs Harmful  Organize your classmates based on 3 categories  Define the basis of your categorization CONCEPT CATEGORY  Mentally possessed idea or  A set of objects or entities notion (i.e. concepts) that ‘belong’  Mental representation of a or are grouped together class or individual CAT = Category  mental representation of a (all the entities in the real world that category are appropriately categorized as cats) CAT = Concept (Whatever psychological state signifies thoughts of cats ) COGNITIVE PSYCHOLOGY  Is the ability to categorize innate in humans?  Infants’ ability to distinguish what they perceive provided evidence that the ability to categorize is INNATE in humans  Basic types of categories? Perceptual  Categorization based on SENSORY input Categories  Categorization based on ABSTRACTION Conceptual Categories Perception Categorization Cognition Categorization based on Categorization based on SENSORY input ABSTRACTION  Taste  Emotions  Sour  Fear  Sweet  Anger  Bitter  Joy  Sound  E.g., baby’s ability to distinguish  Other kinds of abstraction speech sounds  Intelligence vs. stupidity  Democracy vs. dictatorship  Melodic vs. atonal  Categorization – the base on which human cognition rests  Because information from the environment comes to us by means of our senses, the properties of environmental stimuli are intimately involved in the way we categorize those stimuli  Sorting ▪ Sorting/classifying/categorizing items is what we do to keep order in our lives.  Categorization – depends crucially on memory  Without the ability to remember what we have experienced in the past, we would have nothing to relate to (i.e. no categories)  Key Question  What criteria do we use to assign concepts to a category?  3 Theoretical Approaches to Categorization  The ‘Exemplar’ Approach  The ‘ Feature’ Approach  The ‘ Prototype’ Approach  Exemplar – every instance of a category stored in memory  Store all examples of category members ▪ Existent members of a category that we have encountered in the past that have enabled us to function in the world ▪ Objects similar to majority of exemplars are classified faster ▪ Classified based on their similarity to stored exemplar Matches examples stored in memory  A dog you saw on TV  Based on our experiences. Your neighbour’s dog Uncle Joe’s dog Your best friend’s dog A puppy in a pet shop   Based on our experiences.  Developed through childhood and beyond.  We construct categories. Neighbor’s A dog you saw at a dog A dog you saw in the dog show store Abandoned dog in an animal shelter in KL  Form categories by specifying characteristics (features ) of a category that are both necessary and sufficient for membership in that category.  If an entity possesses them, it qualifies as a member of the category adult human Husband male married Clear-cut defining features  Bachelor Clear-cut defining features adult human male unmarried  Based on characteristics that are necessary and sufficient.  Dogs:  Size  Color  Shape of ears  Animate  Four legs  Tail  Bark  Furry  Inanimate objects. These are not dogs. Based on what you know about the feature approach, are these considered dogs?  Things are categorized based upon the number of features they share with other members of a category What features or characteristics are necessary to make a cat a cat?  A representation formed of ‘average’ values for the features characterizing the entity  A version of an entity perceived as an ‘average’ (norm, typical)  The best or most representative member of a category  Store a prototypical representation of a concept  Compare new objects with prototypes represented in the mind  Assign to category it most resembles (approximation) ▪ Is fast because we only look for similarity to prototypes  “Average” of that type Far from our expectations Fits our expectations  Far from our expectations  “Average” of that type Fits our expectations Source: http://animals.nationalgeographic.com/ani mals/birds/ostrich/  No single approach for categorization is sufficient.  We make use of a combination of strategies. COGNITIVE PSYCHOLOGY  Anthropological  Perceptual categories: Perceptual Domain Linguists of Color  Sapir-Whorf Hypothesis (also known as the Linguistic Relativity Hypothesis) Because language determines how we think and perceive the world, people who speak different languages think and perceive the world differently. Edward Sapir Distinctions found in a given language will not be the same as those in other language Constructions of language make it relatively easier or more difficult to think in certain ways  Segmentation of color spectrum varied Benjamin Lee Whorf arbitrarily from language to language Read Sobel p. 38 - 42  Anthropological  Perceptual categories: Perceptual Domain Linguists of Color  Study by Berlin & Kay (1969) to test the Sapir- Whorf Hypothesis  20 different languages Lebanese Arabic ▪ Basic color terms followed by 320 color chips Bulgarian (Bulgaria) Catalan (Spain) Edward Sapir Cantonese (China) American English Hebrew (Israel) in color spectrum Hungarian (Hungary) Ibibio (Nigeria) ▪ What different color categories perceived? Indonesian (Indonesia) Japanese (Japan) ▪ What marked boundaries between one Korean (Korea) Mandarin (China) Pomo (California) category to another? Spanish (Mexico) Swahili (East Africa) Tagalog (Philippines) Thai (Thailand) Tzeltal (Mexico) Urdu (India) Benjamin Lee Whorf Vietnamese (Vietnam) Read Sobel p. 38 - 42  Researchers presented the participants with 320 color chips ranging from violet to red.  The participants decided which categories the color were from.  They were also requested to identify the chips that had marked boundaries (i.e., the last chip in each case that could still be considered to belong to the category before another category began). ▪ Findings Human beings perceive 11 basic color categories (disconfirmation of the Sapir-Whorf Hypothesis) Benjamin Lee Whorf Edward Sapir Read Sobel p. 39  Human beings perceive 11 basic color categories (disconfirmation of the Sapir-Whorf Hypothesis)  If there are fewer than 11 basic color categories, then there are strict limitations on what they are. ▪ There is a term for white and black in all languages. ▪ If there are three color terms, the third one is RED. ▪ If there are four color terms, the fourth one is GREEN OR YELLOW.  ‘family’  Categorization using hierarchy resemblances in categorization FURNITURE Superordinate Superordinate level Semantic Category Less detail TABLE, LAMP, CHAIR Most Basic level distinctive attributes KITCHEN CHAIR, LIVING ROOM CHAIR, Subordinate Subordinate level Semantic Highest detail Category Read Sobel p. 41  Furniture Superordinate Category Chair Basic Category Rocking Chair Subordinate Category  Read Sobel p. 40 Raspberry Superordinate level Berries Blackberry Strawberry Oranges Citrus Limes Subordinate level Grapefruit Fruit Watermelon Melons Honeydew Cantaloupe Red Delicious Apples Granny Smith Braeburn Basic level  Categorization based on free sorting (not based on family resemblance principle)  Findings  When people confront the world, they face two (2) sorts of categories ▪ The ones already constructed (employed by culture, experiences) ▪ The ones they must construct for themselves both early in their development and later on Prototype Feature Exemplar Perceptual Hierarchy Free sorting  Difficulty in recognizing and describing something (i.e. animate or inanimate) which used to be recognizable and describable  Due to injury to a particular part of the brain resulting in loss of categorization ability  AGNOSIA (Category-specific recognition deficits) ▪ can perceive objects within the category they have lost but can’t identify them  PROSOPAGNOSIA- loss of ability to categorize or recognize faces Read Sobel p. 43  Human acquire concepts and engage in the process of categorization  Concepts & Categories are intimately connected  Human construct categories from instances, and these categories result in concept  Concept = representations we have of the totality of a category  Our concepts and categories are stored in our brain COGNITIVE PSYCHOLOGY How are such concepts represented in our brain?  Sensation Visual Auditory Obtain Perception Perceptual Illusions Attention Information Memory Processing Store Statement about Representations the world Concept Proposition Single entity or group of entities Rules Analogy Utilize Day-to-day Comparison Specify relationships between similar between proposition situations  Stimulus –response pairings Knowing ‘how’ Knowing ‘what’ General knowledge automatized about concepts abstracted from scripts experience concepts Definite time/place located in personal histories propositions schemata images Sobel p. 68-75  Semantic – abstract and The concept of Acquired Immune general knowledge about Deficiency Syndrome facts and concepts. (AIDS)  Episodic – contains events that we have experienced Yesterday I did personally. some shopping  Procedural – information related to the performance of various skills. Knowledge about how to do something. How to drive a car  Introspection  Suggests that concepts are related – one thing links to another  Empirical inquiry method  Observation – hypothesis  H1= that concepts are represented in our brains as a network ▪ One concept leads to another because aspects, or features, of that concept are linked to features of other concepts Associated concepts Sobel p. 44 - 45  Also known as propositional network.  Generalized knowledge about a situation or an event. Visual Abstraction (inferred)  An expression of the relationship between concepts  A thought that is in some sense complete  Our thought can also be in the form of ▪ Meanings ▪ Verbal / Language  It is the smallest unit of meaning that can be assigned a truth value (McKoon & Ratcliff, 1980)  Truth value = unit of meaning, can be either true or false Sobel p. 46   That is a fudge cake. (unit of meaning)  True? Not true?  Concepts?  Fudge  Cake Proposition expressed in  Argument language-like fashion  The relation between the concepts Language – means of encoding both the concepts from which propositions are Proposition expressed constructed and the propositions themselves only through language? Sobel p. 46-47  The proposition embodied in the sentences:  A robin is a bird,  A robin has wings, and Are either true or false.  Gordie is my uncle Gordie Robin true false  Entities not yet converted into ordinary language but translatable into such language when we need them  To talk about them  To think about them  That propositions are comprised of meaningful concept/relation combinations not yet transformed into language  Meanings / propositions rather than the precise language are later easier to remember  Thought rests on the mental representation of propositions  Thought is associative – moving from one idea to another ▪ Association likely due to shared elements in associated thoughts  But how does the associative process work?  Hypothesis – that meanings and links are stored in propositional, semantic network Concepts = nodes Association = links How does all these work? Theory of Spreading Activation  Originated in the process of creating a computer program that would simulate human memory search  Now supported by neuroscientific evidence  Several key assumptions:  When a concept is being processed, its node is activated to a certain level (i.e. prime others down the line) ▪ Activation spreads out in every direction of the network, lessening at weaker links and strengthening at stronger ones  Wheat Loaf  How does a Slice propositional network work? Sandwich  Spreading activation. BREAD  When the name of a concept is mentioned, Crumbs Toast the node representing that concept is activated. E.g.: Butter BREAD  butter. Milk Cream Dairy  Spreading activation theory  Features:  If the activation is strong enough, it will be attended to.  Frequently used links have greater strength and therefore activation travels faster between 2 nodes (typicality). ▪ E.G.: fruit and apple VS fruit and tomato  The greater the distance between items, the weaker the spread. The greater the number of irrelevant paths (and interfering information), the weaker the spread. ▪ E.G: bread and butter VS bread and milk  animal mammal Distance (big/small) indicates speed access. bird Canary ostrich  Activation released from a concept node continues as long as the node is in use  Hearing/reading/thinking  Activation decreases over time, or when other activities intervenes, dissipating gradually unless something (e.g. repetition) occurs to strengthen it  The greater the number of concepts stimulated, the less activation available for each one  When activation at a particular node derives from more than one source, activation becomes cumulative until it reaches a threshold (i.e. we become aware of it) Sobel p. 50  A person can categorize once he has learned the concept.  There are two types of mental representation  concept based on visual/perception and  proposition based on meaning  Propositional networks consist of nodes and links (associated with one another)  Spreading activation model assumes concepts are “activated,” and that activation can spread to neighboring concepts. COGNITIVE PSYCHOLOGY  Stimulus –response pairings Knowing ‘how’ Knowing ‘what’ General knowledge automatized about concepts abstracted from scripts experience concepts Definite time/place located in personal histories propositions schemata images  A script is a simple, well-structured sequence of events associated with a highly familiar activity  provide the underlying mental frameworks for our procedural knowledge  Each of us continually follow scripts as we move from one activity or task to another  Idea of scripts = to network theory of propositional representations = theory of spreading activation  Example:  Your script for going to class might include the following sequence: 1. Get to class 10 minutes before it is scheduled to start. 2. Wait for students from the previous class to leave. 3. Enter class and find a seat. 4. Take notes on the lecture. 5. Leave when the professor has finished the lecture. Difference between an actor’s script, our scripts have been written into our nervous systems over the course of our lives concepts propositions Semantic networks scripts Are representations all language-like?  Mental images (Visual Representation)  Try This:  Can you picture a flying elephant?  Can you picture a purple dog?  The fact that we could picture them, although they are non-existent indicates that human can visualize a nonexistent entity  Mental imagery = visual perception ▪ Share similar purpose  To identify objects, parts, and characteristics  To track moving objects, to navigate, to search, to reach appropriately  To identify properties of imaged objects, which allows us to retrieve information from memory  Memory retrieval  Problem solving  Producing descriptions  Mental practice  Motivational states  Daydreaming and association  Mental representation of stimuli that are not physically present  How is it possible?  Scientific experiments ▪ Mental Rotation ▪ Image Scanning  Turning imagined objects in the mind’s eye as if looking at real objects  What goes on in the brain as one sees with one’s mind’s eyes correspond directly to what goes on when one sees with one’s actual eyes.  To investigate the time it takes to scan between two locations on a mental image  The distances are embodied in mental images in the same way as in one’s actual visual perception of pictures  When people operate on mental images they appear to go through a process analogous to actually operating on a physical object. What cognitive processes do we engage in when we approach a problem with the intention of solving it?  Problem –the situation people face when they want something but do not know right away what to do to get it (Newell and Simon, 1972).  Want = Tangible or Abstract  To do = physical actions, perceptual activities, mental activities  Problem solving involves  An initial state – the current state,  Goal state (the desired outcome), and  Path for reaching the goal  Comprehension  e.g: Understanding Cognitive Science  Transformation  e.g: Turn expectations into reality  Arrangement  e.g: Playing Scrabble  Difficulty can be measured by:  the length of time it takes to arrive at a solution  whether it is finally solved  Difficulty depends on the interaction of the problem solver with the task environment  Human being operates as information processing system (AI contribution)  Concepts – relations (networks) – memory  Familiarity with domain of the problem  Experts vs Novice ▪ Experts = vast experience gained, store representations of whole “chunks”- straight to the points, directing attention to what matters (organize knowledge differently) ▪ Experts = working from a larger knowledge base & larger repertoire of procedures COGNITIVE PSYCHOLOGY  All rely on memory Research Insights How we represent the How we: world store How we learn retain How we think access How we reason adapt to How we solve use information problems How we communicate  Emphasis on the study of internal mental operations  Computer as a metaphor for MIND  Mental functioning = representation & computation ▪ Cognitive Architecture  The human learner is conceived to be a processor of information in much the same way as a computer  Theoretical Contributions  Modal Memory Model (Atkinson & Shriffin, 1968)  Tulving’s Model (Tulving, 1972)  Sensory store Short-term store  Memory system:  Permanent, structural feature  Control processes (readily modified or preprogrammed) Multistore model Long-term store  Refers to the way information is represented.  Types of coding: Types of coding Example Visual coding Image of a person. E.g., imagining what your professor looks like (mind’s eye). Phonological coding Sound of a person’s voice. E.g., * Most common type for STM remembering the sound of your professor’s voice. Semantic coding Meaning of what the person is saying. * Most common type for LTM E.g., what your professor was talking about (in terms of meaning).  Records information coming from all senses; incoming sensory information remains briefly (i.e. less than a second) before ‘decaying’  Most attention on: ▪ vision (iconic memory) - what you see that persists even after stimulus has terminated ▪ hearing (echoic memory) - sound that persists for awhile after stimulus has terminated  Purpose = to store information with reasonable accuracy just long enough for some of it to be selected for further processing in working memory (or short-term memory).  Capacity = Large (unlimited)  Retains information briefly (30 seconds)  Information forgotten rapidly when new information follows.  Capacity = limited  Receives input from sensory memory and long-term memory.  Storage  Speech like forms  Visual forms  Other senses?   Functions not just as repository for brief storage BUT also a system that:  manipulates information as it is being stored  uses the information to perform various tasks Supervises & integrates information from both as well as from information from LTM Visual & Spatial Perceived Information Sounds  Store large amounts of information for indefinite periods of time (i.e. capacity: unlimited)  Duration: Permanent / long  How does information pass into LTM?  Information from STM constantly being transferred but the transfer depends on individual engagement process (strengthening or weakening the transfer) ▪ Elaboration – involves linking to already stored associations ▪ Mnemonic devices – memory strategy ▪ Rehearsal - repetition  Elaboration  E.g., how is cognitive psychology related to cognitive science?  Mnemonics  Colors of a rainbow = Roy G. Biv  Red, Orange, Yellow, Green, Blue, Indigo, and Violet.  Retrieval = the process of locating information that has been previously stored in LTM  Recall – learners retrieve previously stored information without cues or hints to help them remember. E.g.: essay questions.  Recognition – involves a set of pre-generated stimuli presented to learners for a decision or judgment.  We may forget for various reasons  Failure to encode – information sought during retrieval was never learned in the first place  Failure to retrieve – inability to access previously learned information  Interference – other events or information got in the way of effective retrieval ▪ E.g., the learning of French and German  How memories are recalled? How memories are formed How memories are retained  Categorizes memory according to type remembered:  Declarative Memory ▪ Semantic Memory ▪ a network of concepts/propositions – enabling us to understand ideas, solve problems, use language ▪ Episodic Memory ▪ Occurrences of events  Procedural ▪ Knowledge contained with learned skills or modifiable cognitive operations concepts categories Propositional networks scripts mental imagery  Organize new information into meaningful chunks.  Students to be encouraged to use both verbal and imagery coding.  Encourage deeper processing through elaboration  Encoding and retrieval are interconnected. Successful retrieval depends on meaningful encoding process.  Learning increases when students make meaning (rather than take meaning). 1. What is the difference between concepts and categories? How do we acquire them? 2. What are the three theoretical approaches to categorization? 3. How are concepts and propositions represented in our mind? 4. What does mental imagery mean? Provide specific examples to illustrate your understanding of its meaning. 5. What are the differences between sensory store, short term and long term memory according to the theory proposed by Atkinson and Shriffin (1968)? 6. What are the key ideas in the Tulving Model of Memory?  Problem solving in the workplace.  Problem solving in university.  Memory in the workplace.  Memory and learning.  Experts and novices in the workplace.  Any other topics related to what was covered today. Read Sobel: Chapter 2