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Cognition – 2/e Dr. Daniel B. Willingham Chapter 1 Cognitive Psychologists’ Approach to Research PowerPoint by Glenn E. Meyer, Trinity University ©2004 Prentice Hall 1 Why Make Assumptions? It is difficult to study anything without having some assumptions about the field. There are two assumptions people make about studying the mind. 1. The Starting point for study 2. Beliefs about the mind’s working (vision, attention, memory) If you know the assumptions – it will be clearer to you why cognitive psychologists ask the questions they do. If you understand why they ask the question – you will better understand the answer! ©2004 Prentice Hall 2 Assumption Examples 1. 2. What Needs to Be Explained: Unconscious processes in vision were not considered until modern times – the assumption being that conscious processes are most important. Beliefs that Influence Questions: If the lens in the eye inverts images, how come we don’t see the world upside down? ©2004 Prentice Hall 3 How Did Philosophers and Early Psychologists Study the Mind? • Philosophical Underpinnings • The Beginnings of Modern Psychology • The Response: Behaviorism • Behaviorism’s Success ©2004 Prentice Hall 4 Philosophical Underpinnings • Ancient Greece: • 1. Focus on the study of Perception, Memory and the Nature/Nurture Issue • 2. Three Assumptions & Questions Raised: a. World can be understood & predicted b. Human are part of the physical world c. Explanations of the world should rely on events in the world and not the supernatural or mystical. ©2004 Prentice Hall 5 Philosophical Underpinnings Continued • Dark Ages and Middle Ages • 1. Few Contributions to the Philosophy of Mind • 2. Causes: a. Rome didn’t value knowledge for it’s own sake b. Barbarian invasions, Feudalism, Decline of cities c. Ascendance of Church ©2004 Prentice Hall 6 Philosophical Underpinnings Continued • Renaissance through the 19th Century • 1. Return of the assumptions of the Greeks that the world can be understood, predicted and that this was worthwhile. • 2. Birth of Modern Science and Scientific Method a. World can be understood & predicted b. Human are part of the physical world c. Explanations of the world should rely on events in the world and not the supernatural or mystical. d. The importance of observations • ©2004 Prentice Hall 7 Philosophical Underpinnings - Continued Why didn’t Psychology Started Until 1879? •Humans viewed as nondeterministic •Humans viewed as having free will •This made studying the mind seem futile •Kant: mental processes could not be measured On the Origin of Knowledge •Empiricists – Hobbes, Locke, Berkeley The view that most of human knowledge is acquired over one’s lifetime through experience . •Nativists - Descartes The view that much of human knowledge is innate •Kant - Experience is the teacher but how you experience depends on native categories ©2004 Prentice Hall 8 Philosophical Underpinnings - Continued Perception • Viewed as Part of the Nativist/Empiricist Debate • Berkeley – even seemingly natural processes like depth perception need experience Memory •Empiricists – Were Also Associationists The view that most of human knowledge is acquired over one’s lifetime through experience . •Nativists - Descartes The view that much of human knowledge is innate •Kant - Experience is the teacher but how you experience depends on native categories ©2004 Prentice Hall 9 The Beginnings of Modern Psychology Founding Fathers: • Wilhem Wundt – 1879 – credit for first research lab dedicated to Psychology • Earlier work by James, Fechner, Weber • However, Wundt really gave Psychology the official look and feel of a science: textbooks, symposia, journals, university department, etc. ©2004 Prentice Hall 10 The Beginnings of Modern Psychology - Continued First Schools • • • Structuralism (Wundt) : a. Metaphor was the periodic table of chemistry b. Goal was the describe the structures of thought Functionalism (James) : Emphasis on function of mental processes as compared to structures Both Schools used Introspection: Wundt’s Introspectionism:The method entails observing one’s thought processes, but it was deemed important that a more experienced introspectionist train a novice in the method James : Less dogmatic in his approach. ©2004 Prentice Hall 11 The Response: Behaviorism • Introspectionism was unsuccessful! • Watson – starts a new direction in psychology Behaviorism (1913) “Psychology as the behaviorist views it is a purely objective experimental branch of natural science. Its theoretical goal is the prediction and control of behavior. Introspection forms no essential part of its methods, nor is the scientific value of its data dependent upon the readiness with which they lend themselves to interpretation in terms of consciousness.” – from Psychology as the Behaviorist Views it. ©2004 Prentice Hall 12 The Response Continued: Four Principles of Behaviorism 1. Psychologists should focus only on that which is available. 2. Psychologists should explain behavior, not thought or consciousness. 3. Theories should be as simple as possible. 4. The overarching goal of psychology is to break down behavior into irreducible constructs – the building blocks of behavior. Watson’s candidate was the conditioned reflex. ©2004 Prentice Hall 13 Behaviorism’s Successes • Offered the idea of the reflex as a basic unit of behavior • Pavlov’s Study of Classical Conditioning: Unconditioned Stimulus, Unconditioned Response, Conditioned Stimulus, Conditioned Response – the Classic Dog Salivation Paradigm • Operant Conditioning: Learning whereby the animal (or person) makes a response that has consequences (e.g., reward or punishment). These consequences change the probability that the response will be made again. ©2004 Prentice Hall 14 How Do Cognitive Psychologists Study the Mind? • • • • • • What Behaviorism Couldn’t Do Failures of Behaviorism to Account for Human Behavior The Computer Metaphor and Information Processing The Behaviorist Response Abstract Constructs in Other Fields So What, Finally, Is the Cognitive Perspective? ©2004 Prentice Hall 15 What Behaviorism Couldn’t Do. • Lacked utility in WWII human factor applications • Couldn’t deal with ethological principles (Lorenz): • a. Fixed action patterns Complex behaviors in which an animal engages despite very limited opportunities for practice or reward. Usually taken as evidence for innate or inborn learning. • b. Critical periods A window of opportunity during which a particular type of learning will be easy for the organism. If the critical period is missed, however, the learning will be difficult or even impossible. ©2004 Prentice Hall 16 Failures of Behaviorism to Account for Human Behavior • Problem with human behaviors such as Language : Chomsky’s Criticisms of Skinner’s Verbal Behavior a. Whitehead’s problem of the ‘Scorpion on the Table’ b. Generative nature of language • Didn’t Explain Memory Phenomena such as Bousfield (1953) demonstration of retrieval strategies. Example - Try to recall ten minutes from now: Lion, onion, Bill, firefighter, carrot, zebra, John, clerk, Tim, nurse, cow. ©2004 Prentice Hall 17 The Computer Metaphor and Information Processing • Importance of Metaphor in Psychological Theories Descartes – Nervous System to Hydraulics 19th Century – Brain to a Telephone Switch Board Hebb (1949) – Neural function to solenoids and capacitors • 1950’s – Computer Metaphor for the Mind 1. Artificial Intelligence and computer usage of symbols applied to psychology models 2. Computer use of representation of symbols and processes to manipulate them give insight into study of the mind 3. Hardware/software division in computers applied to brain/ mind ©2004 Prentice Hall 18 The Computer Metaphor - Continued •The Information Processing Model: An approach to studying the human mind. It assumes that humans are processors of information, and that representations and processing operating on them underlie cognition. Assumes also that information is processed in stages. Three Assumptions of Information Processing: 1. Humans are processors of information like computers and information processing supports thought and behavior 2. Representation and processes that operate on these representation underlie information processing 3. Information processing occurs within largely isolate modules which are organized into stages of processing ©2004 Prentice Hall 19 The Behaviorist Response • Information Processing Models relay on abstract constructs ( theoretical sets of processes and representations that you think are useful in explaining some data). For example – short term memory • Behaviorists have three objections to abstract constructs 1. Constructs can be circular 2. They divert attention from behavior – which is the true subject matter of psychology, not thought 3. They are impossible to verify as they are not observable ©2004 Prentice Hall 20 Abstract Constructs in Other Fields • Abstract Concepts are used freely and with rigor in other fields • Artificial Intelligence – Newell and Simon (1956) program to prove formal logic theorems • Neuroscience – Tying brain structure to behavioral problems Ex. – Patient H.M. and the abstract concept of Short Term Memory ©2004 Prentice Hall 21 So What, Finally, Is the Cognitive Perspective? • Behaviorism could account for all human abilities, especially language and memory • Abstract constructs could help in understanding • Neuroscience and A.I. successfully use abstract constructs • The interactions of representations and processes can be compared to a computer ©2004 Prentice Hall 22 Cognitive Perspective - Continued • Chief Assumptions 1.There are representations and processes that operate on them 2.We can discover them ©2004 Prentice Hall 23