What is Cognitive Psychology?

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Feb 23, 2014 (3 years and 7 months ago)

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What is Cognitive Psychology?


Broad Definition


empirical investigation of mental
events and knowledge involved in recognizing an
object, remembering a name, having an idea,
understanding a sentence, and solving a problem



Specific Definition

-

the empirical investigation of
mental processes and activities used in perceiving,
remembering, and thinking, and the act of using
those processes.



“Pay attention!”


Concept: Attention
--

how we filter or select important information
from the environment.



“I don’t know.”


Concept: Knowledge
--

the store of general information and
algorithms for performing tasks.



“I don’t remember.”


Concept: Memory
--

a process for storing, retrieving and working
with information.



“I can’t decide.”


Concept: Decision making


set of higher
-
level processes that
work together allow us function day to day

History of Cognitive Psychology


Early history


Philosophical roots


Socrates


interested in the origins of
knowledge



Aristotle


interested in origins of knowledge &
memory


Proposed first theory of memory


Descartes


how is knowledge represented
mentally


History of


Recent history


Psychological roots


Wilhelm Wundt (1879)


First psychological laboratory in Leipzig, GE


Founder of psychology as a science


Many early psychologists had roots in Wundts lab

»
Produced over 200 Ph.D students in philosophy and
psychology


Topic: Human cognition


Used introspection to report contents of consciousness

History of


Edward Titchner


Student of Wundts, taught at Cornell University in
1892


Proponent of introspection


Narrow view of psychology

»
Excluded mental illness, education apps., and social
psych, b/c not open to introspection

»
Note: Method defined what was allowable science


Founder of Structuralism

»
Study of: Sensations, images, and feelings that were
elements of the mind


Often argued with Wundt over findings

History of


Herman von Ebbinghaus


Contemporary of Wundt in GE


Big influence on cognitive psych.


Developed method for studying forgetting as function of time

»
Stimuli: lists of Consonant
-
Vowel
-
Consonant’s (CVC’s)

»
Method: Learn list of CVC’s, count number of trials to
recall perfectly


Wait 2 days


re
-
learn list.

»
Savings score = # of trials to learn the 1
st

time
-

# of trials to
learn 2
nd

time


One subject entire career


himself


Learned over 40,000 CVC’s

History of


William James


Wundt’s student, hired at Harvard


Philosopher, but started first American psych. lab


Proposed Functionalism


Stressed the functions over the mind rather than contents

»
How does mind adapt to new circumstances?

»
Proposed multicomponent memory system: Primary
Memory vs. Secondary memory


Authored: Principles of Psychology, chapters on
Sensation, perception, attention, consciousness, memory,
reasoning

History of


Modern History


Human Performance (WWII)


Attention and perception,


training of solders to use radio and radar


Signal detection


Blips on radar or sonar


Information theory




abstract method for analyzing information processing


History of


Artificial intelligence


How can we make computers behave intelligently?


Contributed host of concepts


Idea of study machine, allowed us to study our own
processes


Linguistics


Interested language and language development


Contributed new mode of analyzing structure of
language

Emergence of Cognitive
Psychology


1950’s


1970’s, no agreed upon date


Ulric Neisser’s “Cognitive Psychology” text
published in 1967


Why did Cog. Psyc emerge?


Two major factors


Dissatisfaction w/ behaviorism’s account of complex behavior
(e.g., Chompsky’s new model of language)


Convergence of several other fields during WWII


Linguistics, Human performance, AI

Contributors to Cog. Psych


Human Performance


Abstract way to analyze processing of info.
(development of psychological tools!)


Research ideas in attention and perceptions


AI


Idea of computer as info. Processor


Computer model


Tool for studying cognition


Focus on complex processing (decision making,
reasoning)

Contributors to Cog. Psych


Linguistics & Verbal learning


Questions about language and its complexity


Reason to reject behaviorism


Complexities of lang. Not handled by behaviorism


Philosophy


Age old questions about knowledge and Memory


Behaviorism


Strong empirical methods and laboratory research

Summary


Cog. Psych began with Wundt


Cognitive issues of mental states


But, introspection method not strong


Replication difficult, methodology determined acceptable sub
-
disciplines


These problems fueled behaviorist movement


Behaviorism was major paradigm from 1910’s to
1960’s


Focus shifted to overt behavior


Stimulus


response


Mind considered a black box, can’t study what you can’t see,
hear, feel, or touch


Psychologists need reason to abandon behaviorism


Linguistic’s criticisms provided the stimulus



Summary


War time efforts
-

scientists from different fields
came together for one purpose


Focus on attention and perception


Expansion of methodological toolboxes


Enabled Psychologist to go beyond S
-
R psych.


Idea of humans as “Active” info. Processors


Contrast with behaviorism


Organisms respond to
environment


Invention of computer & focus on mental
processes


Chompsky’s review of Skinner’s book on
language


Illuminated inadequacies of behaviorism


Cognitive Psychology


Information processing approach


decomposition of mental processes


Multi
-
component memory system


Assumptions of Cog. Psych.


Mental processes exist


People are active information processors


Mental processes and structures can be revealed
by time and accuracy measures

Environmental

Stimuli


Sensory

Memory

Short
-
term /
Working

Memory

Long
-
term Memory

&

Knowledge

Cognitive

Psychology

is concerned with

what goes on in here.

Overt
Response

Behavior

Info. Processing model

Component of Model


Sensory memory


input device


What info is sent to the processor


Short
-
term / Working memory


Central processor, actively processes info


Long
-
term memory / Knowledge


Library of programs, algorithms, data, and
experiences that are stored for use


Note similarities to computer!

Sternberg Paradigm


Test of how info is processed


Subjects (Ss) memorize list of digits

{4, 6, 5, 9, 3, 2}


Given recognition test

9?

Yes/No


Measure both accuracy and reaction time (Msec.)

Some trials were false (8?)

Some were true (9?)


Think in terms of Memory
system!

9

6

5

9

3

2

4

LTM

STM / WM

-

-

+

-

-

-

Decision

Results

350
400
450
500
550
600
650
0
2
4
6
8
String size
Msec
Perceive
Stimulus

Generate
response

Make
decision

9=9?

9=3
?

9=6?

9=2
?

Perceive
Stimulus

Generate
response

Make
decision

7=9?

7=3?

7=6?

7=2?

6, 9, 3, 2

9?

7?

What would happen if the search string were 6 items?

What would happen if degraded the probe?

What would happen if we biased the decision process?

Memory Systems


Time to respond was linear function of size
of search string


Each element added 38 msec to search time


Serial position did not matter!


Thus, search is exhaustive


Sternberg’s conclusion: Ss engaged in serial
matching process