Intro to Cognitive Psych

Introduction to Cognitive Psychology Copyright © Allyn & Bacon 2005 What is Cognitive Psychology?  The scientific study of how people think the structures and processes used to produce internal mental representations and how they are realized in the brain. Attending to information Gaining information from the world Storing information Processing information Solving problems, learning, language       Neisser ’67: cognition refers to all processes by which the sensory input is transformed, reduced, elaborated, stored, recovered and used… it is apparent that cognition is involved in everything a human being might possibly do; that psychological phenomena is a cognitive phenomena. Copyright © Allyn & Bacon 2005 The Domain of Cognitive Psychology  Cognitive psychology draws on theories and techniques from 13 main research areas     Cognitive Neuroscience  Neurological (biological) explanations for cognitive processes Consciousness  Awareness and subjective experience Attention  Capacity for processing information Sensation/Perception  How information enters the cognitive system and how it is interpreted Copyright © Allyn & Bacon 2005 The Domain of Cognitive Psychology      Pattern Recognition  Inclination to process information holistically How information is stored and recalled How information is represented in the brain and mind Internal representations of the visual world Tool for thinking, communicating, etc. Memory  Representation of Knowledge  Imagery  Language  Copyright © Allyn & Bacon 2005 The Domain of Cognitive Psychology  Cognitive Development  Development of cognitive abilities over the lifespan Overcoming obstacles and adapting to changing environments  Problem Solving and Creativity   Decision Making and Reasoning  Formation and use Capacity for cognition  Human and Artificial Intelligence  Copyright © Allyn & Bacon 2005 A Brief History…  Early Thoughts on Thinking  In Western Civilization: rooted in ancient Greek philosophy of Plato and Aristotle (4th-5th century BC) on the nature and origin of knowledge  Led to the centuries-old debate of nature vs. nurture   Empiricism   All knowledge comes from life experience Children are born into the world with innate knowledge Nativism  Defining knowledge today= storage and organization of information in memory  Supports both sides of nature vs. nurture  – debate still going….. 4th Aristotle Century BCE Early Dissectors & Galen 2nd Century AD [Brain controlled nervous system but nothing to do w/ thinking or soul] Copyright © Allyn & Bacon 2005 Heraclitus 6th Century BCE [mind is an enormous, unreachable space] [heart was the source of nervous control and the “seat of the soul” (mind)] A Brief History…  Renaissance (16-17th century AD)  Philosophers/theologians agree:  Knowledge located in the brain  Knowledge acquired through physical senses and divine sources Mechanistic thinking led to the split in thinking about the mind and body known as the mind-body problem  René Descartes (1596-1650)   Dualism = the belief that the body and mind are separate - body (machine) was what all animals had in common (study-able), mind was exclusively human (not available to scientific study) Monism = the belief that the body and mind are the same and so both can be studied  Thomas Hobbs -- disagreed  Copyright © Allyn & Bacon 2005 A Brief History…  18th Century AD  Philosophy/theology vs. empirical exploration (scientific research) first starts to split British Empiricists (Berkeley, Hume, Mill & Son) suggest: internal representations and transformations are formed according to definable rules and take time and mental effort = major assumption of modern cognitive psychology Growth in scientific study of the brain and nervous system (beginning of neuroscience) Mid=Luigi Galvani [Hypoth: nerves & muscles work by generating animal electricity themselves] Late=Emil du Bois-Reymond [1st scientist to explain all functions of the brain on electrical and physical grounds] Copyright © Allyn & Bacon 2005   Early=Isaac Newton [Hypoth: vibrating “aetherial” MediumProperties much like biological electricity] A Brief History…  The 19th Century  The split happens and psychology is born (1879)  Early psychology focuses on Mentalism: concern with internal mental representations and how they effect behavior  Theories of mental representations of knowledge divided:    Structuralism: structure of mental representation (the contents and elements)  Wundt (Germany) and Titchener (US)  Wundt’s Introspection was cognitive psychology Functionalism: processes of mental representation (the how and why the mind works)  James (US) and colleagues Pragmatism: the use of mental representation  Brentano (Austria): Actual representations not important– key of cognition is acts of comparing and judging  Dewey (US): thinking, learning and schooling Copyright © Allyn & Bacon 2005 A Brief History…   The Early 20th Century Behaviorism: A school of thought that defines psychology as the scientific study of overt, observable behavior SR  Rise of behaviorism   Introspection method (Whudt) largely ignored in US + conflicting use/results in Europe John Watson (US) (1920) fiercely attacks theories of mental representations  Behaviorism’s major influence (US) for approx. next 50 years   Internal states as intervening variables that were generally ignored Focus on observations of behavior ONLY and rejected use of internal mental representations to explain behavior Copyright © Allyn & Bacon 2005 A Brief History…  The 20th Century Continued …  1950s interest turned again to focus on cognitive/mentalisic topics  1956 MIT Symposium on Information Theory Cognitive Revolution (1950-70s)  Behaviorism not dominant in Europe     Influential Jean Piaget focuses on children’s thinking German Gestalt theorists (task of psychology is to study human thought and behavior as a whole) (1920-70s) Memory research (Bartlett and schemas; Miller’s Magic 7; Tolman & Cognitive Maps, 1932) Donald Broadbent & others combined findings with new area of information theory (abstract way of analyzing the processing of information)  Research on human performance (WWII)    Work of Norm Chomsky and language theorists (195070s) Advent of computer (as a model of the mind) (1960/70s) Copyright © Allyn & Bacon 2005 A Brief History…  Today . . .  Increasing evidence that many mental representations are not the same as external reality (are not isomorphic)– instead are abstract representations  Combination of incoming sensory information, previous rich and complex knowledge and the interaction of the two = abstract/distorted representation stored in memory The field today in the middle of major change = the growth of cognitive neuroscience and its merging with the information processing approach  Copyright © Allyn & Bacon 2005 Conceptual Science  Thinking is not tangible (can’t hand me a memory)  Behavior is the product  It’s latent-- potentially existing but not presently evident or seen Cognitive Models: attempts at describing the mental structures and processes of cognition based on scientific observation    Scientists develop models to provide structure to the overall concept (Memory akin to a file cabinet) The goal is to:        Organize observations Make observations meaningful Integrate the elements derived from observations Develop hypotheses Direct future observations Predict unobserved events Communicate with others Copyright © Allyn & Bacon 2005 Information-Processing Model --the dominant approach- Way to conceptualize cognitive processes as a timeordered sequence of events Analyses thinking as a set of steps in which information is processed  Sternberg’s Paradigm (1966): Keep in mind the three digits: 3 9 7 Asked: is 9 in the set? 9  perceive stimulus  9=3?  9=9?  9=7 make decision– generate response  YES   Three assumptions    Sequential stages Unique processes at each stage Each stage receives and passes on information Copyright © Allyn & Bacon 2005 Parallel Distributed Processing (a.k.a connectionism or neural networks) Model    Rumelhart & McClelland (mid 1980s) Conceptualizing cognitive processes as brain processes The human mind processes information not in sequential steps (information processing model) but instead knowledge is represented in a web-like network of connections among thousands of interaction processing units (through excitation and/or inhibition of neural cells). Key idea= the brain does not store memory in any single neuron or set of neurons but instead in an entire ensemble of neurons distributed throughout several parts of the brain   Knowledge is a web-like patterns of neural activation Copyright © Allyn & Bacon 2005 Evolutionary Cognitive Psychology Model   Steve Pinker & Roger Shepard Understanding cognition through evolution concepts– all cognition and brain structures interpreted in terms of the long-term biological and evolutionary history of our species.    Founded in the tradition of Charles Darwin (Natural Selection) Seeks explanation of psychological processes that are consistent with what is know about evolution and adaptation Major premise= there are universal human cognitive attributes and these attributes are the result of evolved psychological mechanisms, not of social interaction. Copyright © Allyn & Bacon 2005 Cognitive Neuroscience Model  the study of the neural mechanisms (biological foundations) of cognition  Gaining importance in contemporary cognitive psychology due to advances in technology   Better understanding of the biology of the brain Developing theory and research approaches that unite cognitive models and neuroscience Copyright © Allyn & Bacon 2005