Psyc 3705, Cognition--Introduction
Sept. 13, 2013
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
 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
A brief history of Cognitive Psychology
The domain of cognitive psychology
Cognitive Psychology: Introduction
 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?
The domain of Cognitive Psychology
 A brief history of Cognitive
Psychology
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Psyc 3705, Cognition--Introduction
The First Cognitive Psychologists
Sept. 13, 2013
A Modern Example of a Simple
RT Task
 Donders (1868)
Mental chronometry
Measuring how long a cognitive
process takes
p
Reaction
Reaction--time (RT) experiment
An Example of a Choice RT 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
The First Cognitive Psychologists
 Donders (1868)
 Helmholtz (~1860s)
Mental responses cannot be
measured directly but can be inferred
from the p
participant’s
p
behavior
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
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Psyc 3705, Cognition--Introduction
Sept. 13, 2013
The First Cognitive Psychologists
The First Cognitive Psychologists
 Ebbinghaus (1885)
 Ebbinghaus (1885/1913)
Read list of nonsense syllables aloud
many times to determine number of
repetitions
p
necessary
y to repeat
p
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
The First Cognitive Psychologists
 Ebbinghaus (1885/1913)
Savings =
[(initial repetitions) – (relearning
repetitions)]
p
)] / ((initial repetitions)
p
)
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
Ebbinghaus,, 1885/1913.)
The First Cognitive Psychologists
The First Cognitive Psychologists
 Wundt around 1879
 Wundt around 1897
First psychology laboratory
University of Leipzig, Germany
RT experiments
i
t
Approach = Structuralism
Experience is determined by combining
elements of experience
p
called sensations
Method = Analytic introspection
In response to stimuli, participants
described experiences
• Also thought processes
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Psyc 3705, Cognition--Introduction
The First Cognitive Psychologists
Sept. 13, 2013
The Gestalt Philosophy
 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
The whole is greater than the
sum of its parts
 Studied people’s subjective
experiences of stimuli
• Focused on how people impose
structure
The First Cognitive Psychologists
The Rise of Behaviorism
 John Watson noted two problems with
studying mental processes:
 John Watson proposed a new approach
called behaviorism
Extremely variable results from
person to p
p
person
Results difficult to verify
Eliminate the mind as a topic of study
Instead,
Instead study directly observable
behavior
Invisible inner mental processes
The Rise of Behaviorism
Classical Conditioning
 Watson & Rayner (1920/2000) – “Little
Albert” experiment
 Pair a neutral event with an event
that naturally produces some
outcome
 After many pairings,
pairings the “neutral”
neutral
event now also produces the
outcome
Classical conditioning of fear
http://www.youtube.com/watch?v=Xt0u
cxOrPQE
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Psyc 3705, Cognition--Introduction
Sept. 13, 2013
Pavlov’s Discovery: Classical
Conditioning
The Rise of Behaviorism
 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
The Rise of Behaviorism
The Rise of Behaviorism
 Skinner (1950s)
 Skinner (1950s)
Interested in determining the
relationship between stimuli and
response
p
B. F. Skinner
 Interested in determining the relationship between stimuli
and response
Operant conditioning
Shape
Sh
b
behavior
h i b
by rewards
d or
punishments
Behavior that is rewarded is more
likely to be repeated
Behavior that is punished is less
likely to be repeated
1904--1990
1904
Timeline: Early Experiments
studying the mind in the 1800s
and the rise of behaviorism in the
1900s
The Decline of Behaviorism
 A controversy over language acquisition
 Skinner (1957)
Argued children learn language
through operant conditioning
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Psyc 3705, Cognition--Introduction
Sept. 13, 2013
The Decline of Behaviorism
The Decline of Behaviorism
 A controversy over language acquisition
 The Misbehavior of Organisms (1960s)
 Skinner (1957)
 Chomsky (1959)
 Children do not only
y learn language
g g through
g
imitation and reinforcement
Attempts to condition animal
behavior did not work
Animals
Animals’ builtbuilt-in instincts prevailed
Say things they’ve never heard
Often rewarded for incorrect language
 Language must be determined by inborn
biological program
The Decline of Behaviorism
 Tolman (1938) trained rats to find food in
a fourfour-armed maze
 Rats learned to go immediately to the food
The Decline of Behaviorism
 Tolman (1938)
 Two competing interpretations of results:
Behaviorism
Rats learned “Turn
Turn right for food
food”
Tolman’s hypothesis
Rats created a cognitive map of the maze
The Decline of Behaviorism
 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
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Psyc 3705, Cognition--Introduction
Sept. 13, 2013
The Cognitive Revolution
The Cognitive Revolution
 Shift from behaviorist’s stimulusstimulusresponse relationships to an approach
that attempts to explain behavior in
terms of the mind
 Information
Information--processing approach
Flow diagram for an early
computer.
A way to study the mind created from
insights associated with the digital
computer
p
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?
The Cognitive Revolution
The Cognitive Revolution
 Cherry (1953)
 Broadbent (1958)
 Dichotic listening
Present message A in left ear
Present
P
t message B in
i right
i ht ear
To ensure attention, shadow one
message
Flow diagram representing what
happens as a person directs attention
to one stimulus
Unattended information does not
pass through the filter
 Participants were able to focus only on
the message they were shadowing
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Psyc 3705, Cognition--Introduction
FIG 1.12
Sept. 13, 2013
Researching the Mind
 Behavior approach measures
relationship between stimuli and
behavior
y
g
approach
pp
measures
 Physiological
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
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
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Psyc 3705, Cognition--Introduction
Results of the Gais et al. (2006)
experiment
Sept. 13, 2013
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
p
from long
g history
y of p
psychology
y
gy
 Developed
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