What is cognitive
psychology?
Cognitive psychology is the study of
perception, attention, memory, language,
and thinking in humans...how we know
about the world.
...the scientific study of the human mind
and information processing
Related to other fields - linguistics,
computer science, philosophy,
development, etc.
Scientific Study of Info
Processing...
Scientific study: Based on the
experimental method, empirical, scientific.
Human information processing: People
sometimes operate as information
processors.
Information comes from the environment, is
stored briefly, some is selected for additional
processing, something is done to it, it may
result in some additional behavior.
Some examples of
questions of interest:
What is the capacity of short-term
memory?
How is short-term memory searched?
How long can memories last?
How do people understand language?
What is attention?
Why do we study it?
 Theoretical reasons - to  Practical reasons learn more about the
to develop better
processes that underlie
human-machine
our ability to represent
interfaces, develop
information about the
improved teaching
world in
methods,
memory, how language
understand where
works, and how we
things like
solve problems, how
stereotypes come
we learn things, etc
from, etc.
Models of Cognition
Current approaches to studying cognition
The primary approach to cognitive
psychology today is information
processing.
The information processing approach
assumes that information from the
environment undergoes a series of
transformations as it is processed by
different cognitive systems
Information Processing
Approach
Assumptions of Info Proc.
Approach
Cognition occurs through series of
sequential stages
each stage performs unique process on
incoming info received from environment
(“internal representations”) or other
stages
Response is assumed to be the product of
these processes
2 Issues Result…
What are the stages through which
information passes?
In what form is the information
represented in the human mind?
Domain of Cognitive Psych
The field draws off research, theory and
expertise from at least 12 different areas
Each of these areas are covered in dif
chapters throughout the book
Areas in Domain
Cognitive
Neuroscience
Perception
Attention
Memory
Representation of
Knowledge
Imagery
Language
Developmental
Psychology
Thinking and concept
formation
Human intelligence
Artificial Intelligence
Pattern Recognition
pre-20th century history of
cognitive psychology
Aristotle - How do we classify objects into
groups?
Descartes - What is the relationship between
the mind and the body?
Locke - How much do environmental and
genetic influences affect perception?
Ebbinghaus - Can we quantify how
information is retained and retrieved from
memory?
Bryan & Harter - What happens as a task
becomes well-learned?
early 20th century to late
1940' s
behaviorism - rely only on things that are
observable; concept of 'mind' untenable
SR chaining - stimulus®response
verbal learning - SR chaining applied to
language; word associations
late 1940' s to 1950' s - dissatisfaction
with behaviorism and verbal learning
Reemergence of Cognitive
Psych
The failure of behaviorism
Emergence of communication theory
signal detection , attention, cybernetics, and
information theory experimented
Modern linguistics
Memory Research
Computer Science and tech advances
Cognitive Development
Cognitive Revolution
The changes in American psychology have
been so profound over the last 50 years
that it has been called the cognitive
revolution
Levels of description in
cognitive psychology
Theories exist at several levels of
description:
1.Computational theory - description of
processing, input/output, purpose of
computation (flowchart)
2.Algorithmic level -implementation of
computational theory; exact nature of
computation is described
3.Hardware level - physical realization of
computational and algorithmic levels; i.e., the
Models vs. Theories
theory : comprehensive explanation of a
cognitive phenomenon based on a
detailed description of the phenomenon
that is derived from experimental
evidence.
a model is either a mathematical
expression derived from a theory that can
be used to summarize and predict
empirical data, or a computer program
derived from a theory that simulates and
predicts empirical data.
Cognitive Models and
Conceptual Science
In general, most hypotheses about the
mind come from behavioral studies
i.e., seeing what people do in psychological
experiments
However, cognitive psychology also
considers information acquired through
modeling cognitive processes, analyzing
impaired systems, and introspection.
Cognitive Psychology and
Conceptual Science
Conceptual science - very general,
consequences of observations,
metaphorical
Cognitive Models - abstract organizational
ideas derived from inferences based on
observations; part of conceptual science
Specialized forms of scientific concepts that
have the same purposes
used to describe the detection, storage and
use of information within the “system”
Modeling makes explicit the assumptions underlying
a theory of cognition
tests the theory
Ex.) Information Processing Model
Computer Modeling
designing a program to run on a
computer to simulate what a human does
should be grounded in what humans actually
do
caveat - there are sometimes several means
to the same end
basic types of models
Semantic networks
network of interconnected nodes;
nodes stand for characteristics
links between nodes describe relationships
between nodes.
e.g., robin - bird - animal
basic types of models
Connectionist networks /neural networks
/Parallel Distributed Processing models
attempt to simulate characteristics of
information processing among neurons.
Connectionist networks can learn.
Cognitive Science (computer science +
neuroscience + cognitive psych)
basic types of models
cognitive neuropsychology examining cognitive performance in braindamaged patients
explain impairment in terms of theories from
cognitive psychology
patterns of impairment may also be able to
inform theories of normal cognitive
functioning
 e.g., differential impairment of long-term and
short-term memory systems in some patients
Problems with cognitive
neuropsychology model
extensive (non-local) nature of brain
damage
individual differences among patients
ability of other modules to take over
functioning of impaired modules
basic types of models
Cognitive Bionomics
evolutionary psychology + biology +
cognition
Cognition can be best understood within
the context of human physical and social
evolution