What is Cognitive Psychology Broad Definition empirical investigation

What is Cognitive Psychology? • Broad Definition –empirical investigation of mental events and knowledge involved in recognizing an object, remembering a name, having an idea, understanding a sentence, and solving a problem • Specific Definition - the empirical investigation of mental processes and activities used in perceiving, remembering, and thinking, and the act of using those processes.

• “Pay attention!” – Concept: Attention -- how we filter or select important information from the environment. • “I don’t know. ” – Concept: Knowledge -- the store of general information and algorithms for performing tasks. • “I don’t remember. ” – Concept: Memory -- a process for storing, retrieving and working with information. • “I can’t decide. ” – Concept: Decision making – set of higher-level processes that work together allow us function day to day

History of Cognitive Psychology • Early history – Philosophical roots – Socrates – interested in the origins of knowledge – Aristotle – interested in origins of knowledge & memory • Proposed first theory of memory – Descartes – how is knowledge represented mentally

History of • Recent history – Psychological roots – Wilhelm Wundt (1879) • First psychological laboratory in Leipzig, GE – Founder of psychology as a science – Many early psychologists had roots in Wundts lab » Produced over 200 Ph. D students in philosophy and psychology • Topic: Human cognition – Used introspection to report contents of consciousness

History of – Edward Titchner • Student of Wundts, taught at Cornell University in 1892 – Proponent of introspection – Narrow view of psychology » Excluded mental illness, education apps. , and social psych, b/c not open to introspection » Note: Method defined what was allowable science – Founder of Structuralism » Study of: Sensations, images, and feelings that were elements of the mind – Often argued with Wundt over findings

History of – Herman von Ebbinghaus • Contemporary of Wundt in GE – Big influence on cognitive psych. – Developed method for studying forgetting as function of time » Stimuli: lists of Consonant-Vowel-Consonant’s (CVC’s) » Method: Learn list of CVC’s, count number of trials to recall perfectly Wait 2 days re-learn list. » Savings score = # of trials to learn the 1 st time - # of trials to learn 2 nd time – One subject entire career – himself – Learned over 40, 000 CVC’s

History of – William James • Wundt’s student, hired at Harvard – Philosopher, but started first American psych. lab • Proposed Functionalism – Stressed the functions over the mind rather than contents » How does mind adapt to new circumstances? » Proposed multicomponent memory system: Primary Memory vs. Secondary memory – Authored: Principles of Psychology, chapters on Sensation, perception, attention, consciousness, memory, reasoning

History of • Modern History – Human Performance (WWII) • Attention and perception, – training of solders to use radio and radar • Signal detection – Blips on radar or sonar • Information theory – – abstract method for analyzing information processing

History of – Artificial intelligence • How can we make computers behave intelligently? • Contributed host of concepts – Idea of study machine, allowed us to study our own processes – Linguistics • Interested language and language development • Contributed new mode of analyzing structure of language

Emergence of Cognitive Psychology • 1950’s – 1970’s, no agreed upon date • Ulric Neisser’s “Cognitive Psychology” text published in 1967 • Why did Cog. Psyc emerge? – Two major factors • Dissatisfaction w/ behaviorism’s account of complex behavior (e. g. , Chompsky’s new model of language) • Convergence of several other fields during WWII – Linguistics, Human performance, AI

Contributors to Cog. Psych • Human Performance – Abstract way to analyze processing of info. (development of psychological tools!) – Research ideas in attention and perceptions • AI – – Idea of computer as info. Processor Computer model Tool for studying cognition Focus on complex processing (decision making, reasoning)

Contributors to Cog. Psych • Linguistics & Verbal learning – Questions about language and its complexity – Reason to reject behaviorism • Complexities of lang. Not handled by behaviorism • Philosophy – Age old questions about knowledge and Memory • Behaviorism – Strong empirical methods and laboratory research

Summary • Cog. Psych began with Wundt – Cognitive issues of mental states – But, introspection method not strong • Replication difficult, methodology determined acceptable subdisciplines • These problems fueled behaviorist movement • Behaviorism was major paradigm from 1910’s to 1960’s – Focus shifted to overt behavior • Stimulus response • Mind considered a black box, can’t study what you can’t see, hear, feel, or touch – Psychologists need reason to abandon behaviorism • Linguistic’s criticisms provided the stimulus

Summary • War time efforts - scientists from different fields came together for one purpose – Focus on attention and perception – Expansion of methodological toolboxes • Enabled Psychologist to go beyond S-R psych. – Idea of humans as “Active” info. Processors • Contrast with behaviorism – Organisms respond to environment • Invention of computer & focus on mental processes • Chompsky’s review of Skinner’s book on language – Illuminated inadequacies of behaviorism

Cognitive Psychology • Information processing approach – decomposition of mental processes – Multi-component memory system • Assumptions of Cog. Psych. – Mental processes exist – People are active information processors – Mental processes and structures can be revealed by time and accuracy measures

Info. Processing model Environmental Stimuli Cognitive Psychology is concerned with what goes on in here. Sensory Memory Short-term / Working Memory Long-term Memory & Knowledge Overt Response Behavior

Component of Model • Sensory memory – input device – What info is sent to the processor • Short-term / Working memory – Central processor, actively processes info • Long-term memory / Knowledge – Library of programs, algorithms, data, and experiences that are stored for use †Note similarities to computer!

Sternberg Paradigm • Test of how info is processed • Subjects (Ss) memorize list of digits {4, 6, 5, 9, 3, 2} • Given recognition test 9? Yes/No • Measure both accuracy and reaction time (Msec. ) Some trials were false (8? ) Some were true (9? )

Think in terms of Memory system! STM / WM + - 9 Decision 4 6 5 9 3 2 LTM

Results

6, 9, 3, 2 9? Perceive Stimulus 9=6? 9=9? 9=3? 9=2? Make decision Generate response 7? Perceive Stimulus 7=6? 7=9? 7=3? 7=2? Make decision Generate response What would happen if the search string were 6 items? What would happen if degraded the probe? What would happen if we biased the decision process?

• Time to respond was linear function of size of search string – Each element added 38 msec to search time • Serial position did not matter! – Thus, search is exhaustive • Sternberg’s conclusion: Ss engaged in serial matching process