CHAPTER 1
INTRODUCTION TO COGNITIVE PSYCHOLOGY
The Complexity of Cognition
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Cognition involves
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Perception
Paying attention
Remembering
Distinguishing items in a
category
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Understanding and production
of language
Problem solving
Reasoning and decision-making
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Visualizing
All include “hidden”
processes of which we
may not be aware
Cognitive Psychology
– The branch of psychology concerned with the scientific study of the mind
– Cognition
refers to the mental processes, such as perception, attention, and memory,
that are what the mind does
Some Questions to Consider
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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?
How are models used in cognitive psychology?
The First Cognitive Psychologists
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Donders (1868)
– Measuring how long it takes a person to make a decision
– Reaction-time (RT) experiment
• Measures
interval between stimulus presentation and person’s response to
stimulus
– Simple RT task: participant pushes a button quickly after a light appears
– Choice
RT task: participant pushes one button if light is on right side, another if light
is on left side
– Choice RT – Simple RT = Time to make a decision
• Choice RT = 1/10 sec longer than Simple RT
• 1/10 sec to make decision
– Mental
responses cannot be measured directly but can be inferred from the
participant’s behavior
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Wundt (1897)
– First psychology laboratory
– University of Leipzig, Germany
– RT experiments
– Approach
Structuralism: experience is determined by combining elements of experience
called sensations
– Method
Analytic introspection: participants trained to describe experiences and thought
processes in response to stimuli
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Ebbinghaus (1885/1913)
– Read
list of nonsense syllables aloud many times to determine number of repetitions
necessary to repeat list without errors
– After some time, he relearned the list
• Short intervals = fewer repetitions to relearn
– Learned many different lists at many different retention intervals
– Savings = (Original time to learn the list) – (Time to relearn the list after a delay)
– Savings curve shows savings as a function of retention interval
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John Watson noted two problems with this:
– Extremely variable results from person to person
– Results difficult to verify
• Invisible inner mental processes
William James’s Principles of Psychology
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James was an early American psychologist who taught the first psychology course at
Harvard University
Observations based on the functions of his own mind, not experiments
Considered many topics in cognition, including thinking, consciousness, attention,
memory, perception, imagination, and reasoning.
The Rise of Behaviorism
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John Watson proposed a new approach called behaviorism
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Watson and Rayner (1920) – “Little Albert” experiment
– Eliminate the mind as a topic of study
– Instead, study directly observable behavior
– Classical conditioning of fear
– 9-month-old
became frightened by a rat after a loud noise was paired with every
presentation of the rat
Classical Conditioning
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Pair a neutral event with an event that naturally produces some outcome
After many pairings, the “neutral” event now also produces the outcome
Pavlov’s Discovery: Classical Conditioning
The Rise of Behaviorism
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Watson and Rayner (1920) – “Little Albert” experiment
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B.F. Skinner (1940s through 1960s)
– Behavior can be analyzed without any reference to the mind
– Examined how pairing one stimulus with another affected behavior
– 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
The Reemergence of the Mind in Psychology
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Tolman (1938) trained rats to find food in a four-armed maze
Two competing interpretations:
– Behaviorism predicts that the rats learned to “turn right to find food”
– Tolman
believed that the rats had created a cognitive map of the maze and were
navigating to a specific arm
What happens when the rats are placed in a different arm of the maze?
The rats navigated to the specific arm where they previously found food
– Supported Tolman’s interpretation
– Did not support behaviorism interpretation
The Decline of Behaviorism
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A controversy over language acquisition
Skinner (1957) – Verbal Behavior
– Argued children learn language through operant conditioning
• Children imitate speech they hear
• Correct speech is rewarded
Chomsky (1959)
– Argued children do not only learn language through imitation and reinforcement
• Children say things they have never heard and can not be imitating
• Children say things that are incorrect and have not been rewarded for
– Language must be determined by inborn biological program
Studying the Mind
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To understand complex cognitive behaviors:
– Measure observable behavior
– Make inferences about underlying cognitive activity
– Consider what this behavior says about how the mind works
The Cognitive Revolution
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Shift from behaviorist’s stimulus-response relationships to an approach that attempts to
explain behavior in terms of the mind
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Information-processing approach
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Early computers (1950s)
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Cherry (1953)
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– A way to study the mind created from insights associated with the digital computer
– Processed information in stages
• How much information can the mind absorb?
• Attend to just some of the incoming information?
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“Dichotic” listening
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Participants were able to focus only on the message they were shadowing
– Present message A in left ear
– Present message B in right ear
– To ensure attention, shadow one message
Broadbent (1958)
– Flow
diagram representing what happens as a person directs attention to one
stimulus
– Unattended information does not pass through the filter
The Cognitive Revolution
Artificial Intelligence and Information Theory
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Artificial Intelligence
– “making
a machine behave in ways that would be called intelligent if a human were
so behaving.” (McCarty et al., 1955)
– Newell
and Simon created the logic theorist program that could apply rudimentary
logic to creating mathematical theorems
Modern Research in Cognitive Psychology
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How research progresses from question to question
– Start with what is known
– Ask questions
– Design experiments
– Obtain and interpret results
– Use results as the bases for new research questions and experiments
The Role of Models in Cognitive Psychology
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There are two kinds of models to be aware of:
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Structural Models
Process Models
Structural Models
Representations of a physical structure
Mimic the form or appearance of a given object
Process Models
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Represent the processes that are involved in cognitive mechanisms, with boxes usually
representing specific processes and arrows indicating connections between processes