Transcript Document

Theory and Methods
Learning Theory
Define: The more or less permanent
change in behaviour potentiality which
occurs as a result of repeated
practice.
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The change could be permanent or
temporary
The behaviour does not necessarily have
to be observable (fMRI)
Learning Theory
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Classical (Respondent) Conditioning
(or Pavlovian Conditioning)
Pavlov and Watson - conditioned reflex
method
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Reflex - a biologically determined
behaviour that is always elicited by a
particular stimulus
Behaviour is called respondent behaviour
Learning Theory
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Elements of classical conditioning
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US (unconditioned stimulus)
UR (unconditioned response)
CS (conditioned stimulus)
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It can be perceived and attended
Does not elicit UR itself
CR (conditioned response)
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Occurs before UR
Smaller in magnitude than UR
Form of response may be different than UR
Schematic of Elements
1.2
1.2
1
1
0.8
0.8
0.6
0.6
UR
0.4
CS
0.2
US
0
0.4
0.2
CR
CS
US
0
0
15 30 45 60 75 90
0 15 30 45 60 75 90
Learning Theory
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Elements of classical conditioning
(cont.)
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CS preceeds US
CS overlaps with US in time
Example of Acquisition &
Extinction
CS-US Unpaired
CS Alone
CS-US Paired
Acquisition
Extinction
-20
-10
0
10
-5 -4 -3 -2 -1
1 2 3 4 5 6 7 8 9 10
1+ 2+ 3+ 4+ 5+
Learning Theory
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Operant Conditioning (learning)
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Skinner believed in operant behaviours
that are not reflexes but are emitted due to
their consequences
Response/reinforcer (reward) association
Behaviour is an instrument to attain some
end
Example: rats in a maze to get food
T-maze
Multiple T-maze: Honzik (1936)
Constant
Variable
12
10
8
6
4
2
0
Food Box
Start
1
3
5
7
9
11 13
Learning Theory: Operant
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Thorndike - Law of
Effect
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Responses which
produce rewards (or
positive
consequences) will
tend to increase in
frequency
Example: infants
and footkicking
Learning Theory: Operant
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Negative reinforcers
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A response that has the consequence of
removing something unwanted
Punishers
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Consequences that reduce the expression
of a behaviour
Learning Theory
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Habituation
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Simplest form of learning
Most often used with infants
Like classical conditioning, starts with a reflex
With repeated exposure to the eliciting stimulus,
response declines
Dishabituation - the recovery of the reflex
response when a new eliciting stimulus is
presented
Learning Theory
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Habituation (cont.)
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most commonly habituated reflexes are the orienting
response and the startle response
Kellman & Spelke (1983)
Habituate
Unitary Object Test
Two Object Test
Social Learning Theory
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Albert Bandura
Observational learning
 Previous learning was active,
whereas in some learning the child is
passive and just observes
 Imitation - Meltzoff
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deferred imitation
Ethology
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Study of development from an
evolutionary perspective
Imprinting - interaction between biology
and environment
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Lorenz and chicks
Language
Visual deprivation
Research Methods
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Theory - A set of expressions put forth
as an explanation of facts and empirical
findings
A good theory makes predictions as yet
unknown facts
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called a hypothesis
need to test hypothesis
Hypothesis Testing
Research Methods
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Two requirements for testing:
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1) objective methods
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2) measurable behaviors - morality
Types of Research
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Descriptive - observing and recording
Correlational - describes the relation
between two variables
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measured on a -1.00 to 1.00 scale
(correlation coefficient)
severe limitation - correlation does not
indicate causality
Correlations
Types of Research
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Experimental - purpose is to draw
cause-and-effect conclusions
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one variable is manipulated - Independent
variable
effect on the other variable is measured Dependent variable
Developmental Research
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Need to take into account time
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Longitudinal
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same subject is studied repeatedly at
different ages
can be either correlational or experimental
Developmental Research
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Longitudinal (cont.)
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typically, two types of questions
1) Stability
2) Early Experience Effects
Problems 
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subject loss
repeated testing effects
length of the study
Developmental Research
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Cross-sectional
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study children at different ages to examine
differences in behavior at different ages
Problem
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cannot study stability or earlly experience
effects
cohort effect - differences are due to different
age populations being members of different
generations
Developmental Research
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Longitudinal/Cross-Sectional Combo
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also called cross-sequential design
can test for cohort effects & repeated
testing
examine stability and age differences
Microgenetic
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Examining a small group begining at an
age where major development
Example: Perception
Again, problem of repeated testing
Cross-sequential design
Developmental Research
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Case Studies
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typically used in clinical research
study a single individual
Problem of generalizing conclusion to
whole population
Developmental Research
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Cross-Cultural
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Comparative
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compare species
to examine evolutionary issues
mostly, to do studies not possible in
humans