Chapter 1
Introduction to Cognitive Psychology

The Complexity of Cognition

• Cognition involves
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Perception
Attention
Memory
Representation of knowledge
Language
Problem-solving
Reasoning and decision-making
• All include “hidden” processes of which we may not be aware

Some Questions to Consider

• How is cognitive psychology relevant to
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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?

The First Cognitive Psychologists

• Donders (1868)
– Mental chronometry

• Measuring how long a cognitive process

takes
– Reaction-time (RT) experiment
• Measures interval between stimulus presentation and person’s response to stimulus The First Cognitive Psychologists

• Donders (1868)
– 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

Caption: A modern version of Donders’ (1868) reaction-time experiment: (a) the simple reaction-time task; and (b) the choice reaction-time task.

The First Cognitive Psychologists

• Donders (1868)
– Choice RT – Simple RT = Time to make a decision • Choice RT = 1/10th sec longer than
Simple RT

• 1/10th sec to make decision

The First Cognitive Psychologists

• Donders (1868)
– Mental responses cannot be measured directly but can be inferred from the participant’s behavior

The First Cognitive Psychologists

• 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 The First Cognitive Psychologists

• Ebbinghaus (1885)
– Read list of nonsense syllables aloud many times to determine number of repetitions necessary to repeat list without errors

The First Cognitive Psychologists

• Ebbinghaus (1885)
– After some time, he relearned the list

• Short intervals = fewer repetitions to relearn – Learned many different lists at many different retention intervals

The First Cognitive Psychologists

• Ebbinghaus (1885)
– Savings =
[(initial repetitions) – (relearning repetitions)] /
(initial repetitions)
– Forgetting curve shows savings as a function of retention interval

Caption: Ebbinghaus’s retention curve, determined by the method of savings. (Based on data from Ebbinghaus, 1885.)

The First Cognitive Psychologists

• Wundt (1897)
– First psychology laboratory
– University of Leipzig, Germany
– RT experiments

The First Cognitive Psychologists

• Wundt (1897)
– 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

The First Cognitive Psychologists

• John Watson noted two problems with this:
– Extremely variable results from person to person – Results difficult to verify

• Invisible inner mental processes

The Rise of Behaviorism

• John Watson proposed a new approach called behaviorism

– Eliminate the mind as a topic of study
– Instead, study directly observable behavior

The Rise of Behaviorism

• Watson (1920) – “Little Albert” experiment
– 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

• Pair a neutral event with an event that
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naturally produces some outcome
After many pairings, the “neutral” event now also produces the outcome

Pavlov’s Discovery: Classical Conditioning

Caption: Pavlov’s famous experiment paired ringing a bell with presentation of food.
Initially, only presentation of the food caused the dog to salivate, but after a number of pairings of bell and food, the bell alone caused salivation. This