1. Introduction to Cognitive Psychology
Chapter 1
Introduction to Cognitive Psychology

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

3. 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?

4. 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

5. 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

6. ● FIGURE 1.2 A modern version of Donders’ (1868) reaction time experiment: (a) the
simple reaction time task; and (b) the choice reaction time task. In the simple reaction time
task, the participant pushes the J key when the light goes on. In the choice reaction time
task, the participant pushes the J key if the left light goes on and the K key if the right light
goes on. The purpose of Donders’ experiment was to determine
Caption: A modern version of Donders’ (1868) reaction-time experiment: (a) the simple reaction-time task; and (b) the choice reaction-time task.

7. 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

8. The First Cognitive Psychologists
Donders (1868)
Mental responses cannot be measured directly but can be inferred from the participant’s behavior

9. 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

10. 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

11. 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

12. The First Cognitive Psychologists
Ebbinghaus (1885)
Savings = [(initial repetitions) – (relearning repetitions)] / (initial repetitions)
Forgetting curve shows savings as a function of retention interval

13. FIGURE 1.5 Ebbinghaus’s savings (or
forgetting) curve. Taking the percent savings as a
measure of the amount remembered, Ebbinghaus
plotted this against the time interval between
initial learning and testing.
(Source: Based on data from Ebbinghaus, 1885/1913.)
Caption: Ebbinghaus’s retention curve, determined by the method of savings. (Based on data from Ebbinghaus, 1885.)

14. The First Cognitive Psychologists
Wundt (1897)
First psychology laboratory
University of Leipzig, Germany
RT experiments

15. 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

16. 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

17. 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

18. 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

19. 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

20. 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 principle of learning by pairing, which came to be called classical conditioning, was the basis of Watson’s “Little Albert” experiment.

21. The Rise of Behaviorism
Watson (1920) – “Little Albert” experiment
Behavior can be analyzed without any reference to the mind
Examined how pairing one stimulus with another affected behavior

22. The Rise of Behaviorism
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

23. Caption: Timeline showing early experiments studying the mind in the 1800s and events associated with the rise of behaviorism in the 1900s

24. The Decline of Behaviorism
A controversy over language acquisition
Skinner (1957)
Argued children learn language through operant conditioning
Children imitate speech they hear
Correct speech is rewarded

25. The Decline of Behaviorism
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

26. The Decline of Behaviorism
The Misbehavior of Organisms (1961)
Attempts to condition animal behavior did not work
Animals’ built-in instincts prevailed

27. The Decline of Behaviorism
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

28. The Decline of Behaviorism
Tolman (1938)
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

29. Caption: Maze used by Tolman
Caption: Maze used by Tolman. (a) Rat initially explores the maze; (b) then learns
to turn right to obtain food at B when it starts at A; (c) when placed at C, the rat turns left to reach the food at B. In this experiment, precautions are taken to prevent the rat from knowing where the food is based on cues such as smell.

30. 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

31. The Cognitive Revolution
Shift from behaviorist’s stimulus-response relationships to an approach that attempts to explain behavior in terms of the mind

32. The Cognitive Revolution
Information-processing approach
A way to study the mind created from insights associated with the digital computer

33. FIGURE 1.9 Flow diagram for an early computer.
FIGURE 1.11 Flow diagram for Broadbent’s fi lter model of
attention. This diagram shows that many messages enter a “fi lter”
that selects the message to which the person is attending for
further processing by a detector and then storage in memory. We
will describe this diagram more fully in Chapter 4.
Caption: (a) Flow diagram for an early computer. (b) Flow diagram for Broadbent’s filter model of attention.

34. The Cognitive Revolution
Early computers (1950s)
Processed information in stages
How much information can the mind absorb?
Attend to just some of the incoming information?

35. The Cognitive Revolution
Cherry (1953)
Dichotic listening
Present message A in left ear
Present message B in right ear
To ensure attention, shadow one message
Participants were able to focus only on the message they were shadowing

36. The Cognitive Revolution
Broadbent (1958)
Flow diagram representing what happens as a person directs attention to one stimulus
Unattended information does not pass through the filter

37. FIG 1.12
Caption: Timeline showing events associated with the decline of the influence of behaviorism (above the line) and events that led to the development of the information-processing approach to cognitive psychology (below the line).

38. 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

39. 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

40. 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

41. Procedure for Muller and Pilzecker’s experiment
Procedure for Muller and Pilzecker’s experiment. (a) In the immediate condition, participants learned the first list (1) and then immediately learned the second list (2). (b) In the delay condition, the second list was learned after a 6-minute delay. Numbers on the right indicate the percentage of items from the first list recalled when memory for that list was tested later.

42. Researching the Mind – Memory Consolidation
Behavior Approach
Gais et al. (2007) 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

43. Caption: Results of the Gais et al
Caption: Results of the Gais et al. (2007) experiment in which memory for word pairs was tested for two groups. The sleep group went to sleep shortly after learning a list of word pairs. The awake group stayed awake for quite a while after learning the word pairs. Both groups did get to sleep before testing, so they were equally rested before being tested, but the performance of the sleep group was better.

44. 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

45. 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