Psyc 3705, Cognition--Introduction Sept. 13, 2013

Transcription

1 Cognitive Psychology: Introduction COGNITIVE PSYCHOLOGY The domain of Cognitive Psychology A brief history of Cognitive Psychology Professor: Dana R. Murphy, Ph.D. Meeting times: Fridays 9 AM to 11:50 AM Laboratory Sessions: 10 AM to 11:50 AM starting Sept. 20, 2013 Cognitive Psychology: Introduction The domain of Cognitive Psychology A brief history of Cognitive Psychology The domain of cognitive psychology Aspects of Cognition covered: Perception and pattern recognition Attention Memory Representation of knowledge Use and Manipulation of information Individual and situational differences in cognition The domain of cognitive psychology Some questions to consider: How is cognitive psychology relevant to everyday experience? Are there practical applications of cognitive psychology? How is it possible to study the inner workings of the mind when we can t really see the mind directly? What is the connection between computers and the study of the mind? Cognitive Psychology: Introduction The domain of Cognitive Psychology A brief history of Cognitive Psychology 1

2 Donders (1868) Mental chronometry Measuring how long a cognitive process takes Reaction-time time (RT) experiment A Modern Example of a Simple RT Task An Example of a Choice RT Task Donders (1868) Choice RT Simple RT = Time to make a decision Choice RT = 1/10 th sec longer than Simple RT 1/10 th sec to make decision Donders (1868) Mental responses cannot be measured directly but can be inferred from the participant s p behavior Helmholtz (~1860s) Unconscious inference Some of our perceptions are the result of unconscious assumptions we make about the environment We infer much of what we know about the world 2

3 Ebbinghaus (1885) Read list of nonsense syllables aloud many times to determine number of repetitions necessary to repeat list without errors Ebbinghaus (1885/1913) After some time, he relearned the list Short intervals = fewer repetitions to relearn Learned many different lists at many different retention intervals Ebbinghaus (1885/1913) Savings = [(initial repetitions) (relearning repetitions)] / (initial repetitions) Forgetting curve shows savings as a function of retention interval Ebbinghaus s retention curve, determined by the method of savings. (Based on data from Ebbinghaus, 1885/1913.) Wundt around 1879 First psychology laboratory University of Leipzig, Germany RT experiments Wundt around 1897 Approach = Structuralism Experience is determined by combining elements of experience called sensations Method = Analytic introspection In response to stimuli, participants described experiences Also thought processes 3

4 Gestalt Psychology Believed that a reduction of psychological phenomena not possible Must study phenomena in their entirety The whole is greater than the sum of its parts Studied people s subjective experiences of stimuli Focused on how people impose structure The Gestalt Philosophy The whole is greater than the sum of its parts John Watson noted two problems with studying mental processes: Extremely variable results from person to person Results difficult to verify Invisible inner mental processes John Watson proposed a new approach called behaviorism Eliminate the mind as a topic of study Instead, study directly observable behavior Watson & Rayner (1920/2000) Little Albert experiment Classical conditioning of fear cxorpqe Classical Conditioning Pair a neutral event with an event that naturally produces some outcome After many pairings, the neutral event now also produces the outcome 4

5 Pavlov s Discovery: Classical Conditioning Watson and Rayner (1920/2000) Little Albert experiment Behavior can be analyzed without any reference to the mind Examined how pairing one stimulus with another affected behavior Skinner (1950s) Interested in determining the relationship between stimuli and response B. F. Skinner Skinner (1950s) Interested in determining the relationship between stimuli and response Operant conditioning Shape behavior by rewards or punishments Behavior that is rewarded is more likely to be repeated Behavior that is punished is less likely to be repeated Timeline: Early Experiments studying the mind in the 1800s and the rise of behaviorism in the 1900s A controversy over language acquisition Skinner (1957) Argued children learn language through operant conditioning 5

6 A controversy over language acquisition Skinner (1957) Chomsky (1959) Children do not only learn language g through imitation and reinforcement Say things they ve never heard Often rewarded for incorrect language Language must be determined by inborn biological program The Misbehavior of Organisms (1960s) Attempts to condition animal behavior did not work Animals built-in in instincts prevailed Tolman (1938) trained rats to find food in a four-armed maze Rats learned to go immediately to the food Tolman (1938) Two competing interpretations of results: Behaviorism Rats learned Turn right for food Tolman s hypothesis Rats created a cognitive map of the maze Tolman (1938) Started rat at different arm Rat went immediately for the food Studying the Mind To understand complex cognitive behaviors: Measure observable behavior Make inferences about underlying cognitive activity Consider what this behavior says about how the mind works 6

7 Shift from behaviorist s stimulus- response relationships to an approach that attempts to explain behavior in terms of the mind Information-processing approach A A way to study the mind created from insights associated with the digital computer Flow diagram for an early computer. Early computers (1950s) Processed information in stages How much information can the mind absorb? Attend to just some of the incoming information? Cherry (1953) Dichotic listening Present message A in left ear Present t message B in right ear To ensure attention, shadow one message Participants were able to focus only on the message they were shadowing Broadbent (1958) Flow diagram representing what happens as a person directs attention to one stimulus Unattended information does not pass through the filter 7

8 FIG 1.12 Researching the Mind Behavior approach measures relationship between stimuli and behavior Physiological approach measures relationship between physiology and behavior Both contribute to our understanding of cognition Researching the Mind Memory Consolidation Memory for recent events is fragile If processing is disrupted, recent memories can fail to be consolidated New information can interfere with memory consolidation Researching the Mind Memory Consolidation Behavior approach Muller and Pilzecker (1900) had participants learn two lists of words Independent variable: One group learned the second list immediately after the first list The other group experienced a six-minute delay between learning the lists Dependent variable: Memory (recall) for the first list of words Researching the Mind Memory Consolidation Behavior Approach Gais et al. (2006) the effect of sleep on memory consolidation Independent variable: One group learned a list of words shortly before going to sleep The other group, many hours before going to sleep Dependent variable: Memory (forgetting) for the list of words measured two days later 8

9 Results of the Gais et al. (2006) experiment Researching the Mind Memory Consolidation Physiological approach Gais et al. (2007) the effect of sleep on memory consolidation Brain activity at encoding and retrieval Measured using brain imaging (fmri) Results Found differential brain activity between the two groups Cognitive Science Interdisciplinary study of the mind Psychology Computer science Cognitive anthropology Linguistics Neuroscience Philosophy Goal: finding ways to study and understand the inner workings of the mind Cognitive Psychology: Introduction Conclusions Cognitive Psychology Relatively recent field of study Developed from long history of psychology 9