The History and Methods of Cognitive Psychology
• Why look at the history of psychology?
– Science as a process, not a set of answers
– Borrowing and reinventing old ideas
• Movements in the psychology of cognition
– Structuralists: 1870-1920
– Behaviorists: 1920-1960
– Cognitive psychology: 1956-present
Structuralism/Introspectionism
• Methods
– Anectdotes
– Describe sensory experience
• Avoid “stimulus error”
– Stream of consciousness
– Test self
• Ebbinghaus as a cross-over to scientific psychology
• Problems
– Different people get different results
– Cannot introspect on all processes
– Introspections can be wrong
Introspectionism
Wilhelm Wundt
Ebbinghaus: Tested self, but experimentally
Introspections can be wrong
• Unconscious influences on judgments
– Right-side preference
• Change-blindness: difficulty detecting obvious changes
from one scene to another
– And “Change-blindness blindness” - people don’t think that
they would have a hard time detecting obvious changes
Behaviorism
• Only care about behavior
– Don’t hypothesize internal events
• Stimulus-response (S-R) psychology
• Align psychology with science
• Empiricist
– Tabula rasa = blank slate
– Empirical = uses experimental research methods
• Problems with behaviorism
– Animals are not infinitely malleable, nor tabula rasas
– Not just learning S-R combinations
• Tolman’s maze experiments
• Learning by observing - don’t need reward
– Language
Not all associations are equally learnable
Acquired taste aversion is very strong
Taste-to-stomache-ache associations are easily built
Learn
lights->shock
taste->stomache ache
Don’t learn
lights->stomache ache
taste -> shock
There’s more to
association than simply
reinforcement history
Tolman’s cognitive maps
Food
Rat learns more than just the response (route)
necessary to get reward
Learning is possible even if not personally reinforced
Learning by observing (Thorndike, 1911)
Noam Chomsky: Language
cannot be learned solely by
learning stimulus-response
associations.
Cognitive Psychology
•
•
•
•
Mental processes exist and can be studied
Need to give abstract, functional descriptions of behavior
Use rigorous empirical methods
Active processing
– Not just passive response to stimulus
• Understanding minds through decomposition
– Flow charts
• Information processing and representation
– Transformation of information
– Representation = symbol that stands for something the real world
– Computer metaphor
Developing Functional Descriptions
Duplicate?
Add flipped shape to left side?
Duplicate?
Add flipped version of rightmost shape to left side?
Add one?
Mirror
Input
F
ABCDEF
ABCDEF
Flowcharts for breaking down cognition into pieces
Abstract description of the stages necessary for cognition,
and how the stages are ordered and transfer information
Response times for analyzing information processing