Transcript No Slide Title

Cognitive Psychology
EXP 3604
Ira Fischler
• Welcome to the course
• CP in the curriculum
• Web resources
– www.psych.ufl.edu/~fischler
• Course structure and requirements
• CP in science and society
• Scope and nature of CP
A COGNITIVE PSYCHOLOGIST’S
VIEW OF THE ACADEMIC WORLD
neuropsychology
developmental
psychology
evolutionary
psychology
social psychology
anthropology
neuroscience
Cognitive
Psychology
philosophy
education
computer science
humanities and arts
sports & music
WHAT IS COGNITIVE PSYCHOLOGY?
• BY FORMAL DEFINITION
– the study of human mental processes and
their role in perception, attention, memory,
thinking and decision-making (Goldstein)
• BY TOPIC
–
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–
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attention and information processing
memory: representation and dynamics
Language and concepts
thinking and problem solving
• BY ISSUES
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does “subliminal learning” work?
What is the matter in dyslexia?
Do you use the cell phone and drive?
are “recovered memories” reliable?
What is insight? Intuition? Creativity?
Should you get a smallpox vaccination?
Can we increase IQ by training?
GOALS OF COGNITIVE PSYCHOLOGY
to describe human cognition
in terms of
• PERFORMANCE
– how accurate? ..fast? ..much?
• PROCESS
– models of the stages and codes
involved in a cognitive task
• PRINCIPLES
– what is the “functional organization
of the mind?”
COGNITIVE PSYCHOLOGY
Course Goals
In EXP 3604, you will learn about...
• THE COGNITIVE APPROACH
– how to think about cognition like a
cognitive psychologist
• THE METHODS OF THAT APPROACH
– understanding the interplay between
theoretical and experimental tools
• THE NATURE AND LIMITS OF
COGNITION
– how we do those things we do
(e.g., perceive, attend, recall, think…)
• TIPS AND TECHNIQUES FOR
ENHANCING COGNITION
– methods of improving your skills in
learning, remembering and thinking
… and revive that childlike sense of awe
A CAPSULE HISTORY OF
COGNITIVE PSYCHOLOGY
• A VIEW OF PROGRESS IN SCIENCE
– Thomas Kuhn (1962): THE STRUCTURE
OF SCIENTIFIC REVOLUTIONS
– Normal science versus “Paradigm shifts”
– Revolutions in the natural sciences
– Revolutions in the social sciences
– Progress or “cultural construct”?
• PHILOSOPHICAL INQUIRY
– since 500 BC: From Greece to the
Enlightenment
• Plato: innate, ideal “concepts”
(nativism) and knowledge via
reason (rationalism)
• Aristotle: the role of experience in
learning, and observation in
science (empiricism)
• Kant: innate concepts of space,
time and causality; cognitive
“schema”
• Locke and the British Empiricist
tradition
SCIENTIFIC PSYCHOLOGY IS BORN
1850’s: Psychophysics (e.g.,
Fechner)
1880’s: Introspection (e.g., Wundt)
• REACTIONS TO INTROSPECTION’S..
– Elementalism: vs. “global” aspects of
perception > Gestalt Theory (Kohler)
– Accessibility: vs. “imageless thought” >
Psychoanalysis (Freud)
– Structuralism: vs. the “purposiveness” of
cognition > Functionalism (James)
– Scientific validity: vs. problems
with replication & bias >
Behaviorism (Watson)
• THE COGNITIVE REVOLUTION
– 1950s: Information processing
(e.g., Broadbent)
COGNITIVE PSYCHOLOGY IS
BORN (1950 - 1965)
• BEHAVIORISM EVOLVES
– e.g., Lawrence (1952)
• HUMAN FACTORS
– e.g., Broadbent (1955)
• INFORMATION THEORY
– e.g., Shannon (1949)
• LINGUISTICS
– e.g., Chomsky (1957)
• COMPUTER SCIENCE
– e.g., von Neumann (1950)
COGNITIVE PSYCHOLOGY
- e.g., Neisser (1967)
THE INFORMATIONPROCESSING FRAMEWORK
• STAGES OF PROCESSING
– The sequence of mental operations that
occur as we do a task
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•
how many stages?
do they require attention?
are they obligatory?
do any stages occur “in parallel”?
• CODES OF REPRESENTATION
– The form or nature of the information
being processed
• visual or verbal?
• analog or conceptual?
Broadbent’s
“structural”
IP model (1955):
MEMORY STRUCTURES AND
PROCESSES IN
THE “MODAL MODEL”
(Atkinson & Shiffrin, 1968)
sensory
inputs
SENSORY REGISTERS
visual
auditory
tactile
SHORT-TERM STORE (STS)
temporary, working memory
control processes:
- rehearsal
- coding
- decisions
- retrieval strategies
LONG-TERM STORE (LTS)
permanent memory store
USING REACTION TIME TO
STUDY PROCESSING STAGES
Letter-matching: Same or Different?
(Posner & Mitchell, 1967)
Type of Pair
Response
RT
AA, ff, LL etc…
“yes”
msec
Aa, Gg, kK etc…
“yes”
msec
Ad, gF, RM etc…
“no”
msec
Aa requires one additional stage, so
Aa - AA gives the time of that stage
This difference correlates with
verbal SAT scores! (Hunt, 1975)
STAGES AND CODES IN A
SIMPLE PROCESSING TASK
Letter-matching: Same or Different?
(Posner & Mitchell’s “task” IP model,
1967)
Aa
(stimulus appears)
See the letters
Compare the forms
same form?
Name the letters
NO
YES
Compare the names
same
names?
Select response
NO
left key
YES
right key
STRATEGIES OF COGNITIVE
NEUROSCIENCE
• The Coin of the Realm: correlations
between psychological and
neurophysiological events/structures
• Establishing two-way constraints
between levels
– Cognitive psychology as the bootstrap
– Neuroactivity as the bootstrap
• Regions of interest (ROI’s) and
localization of function
– Subtractive versus parametric designs
– Event-related activation “dynamics”
• Covariation and functional networks
– Patterns of correlated activity among
multiple regions of interest
EEG and EVENT-RELATED
POTENTIALS (ERPs)
• Postsynaptic extracellular potentials
vary with neuronal activity
• Masses of pyramidal cells generate
a varying electrical signal, the EEG
• Changes in the EEG that are related
to psychological events (ERPs) can
be seen by averaging
• Various ERP “components” are
sensitive to cognitive processes
MAGNETOENCEPHALOGRAPHY
• methodology
– Incredibly weak magnetic signal
(femtoTeslas)
– Detected by SQUID ($3M, 16,000 lbs,
minus 269 deg C
– Works for neural fields tangental to
surface
MAGENTIC RESONANCE
IMAGING (MRI)
• Align the spins of Water-based
hydrogen atoms by powerful
magnetic field
• Create a “gradient” in the field
• “pulse” the field with
a strong radiofrequency signal that
perturbs the alignment
• Using an RF detector, track the
return to alignment
• With really complex computing,
reconstruct the 3D density of tissue
in the brain
FUNCTIONAL MAGNETIC
RESONANCE IMAGING
(fMRI)
• Oxygenated blood has different
magnetic properties than deoxy
• So comparing MRI between target
task and “control” task (a challenge)
reveals areas of task-related
activation
fMRI (cont’d)
• Event-related fMRI allows tracking
of the “hemodynamic response” to
individual events:
Source: Kwong et al., 1992
COLLECTING EEG
REACTION TIME AND
UNCERTAINTY (Hick, 1952)
Reaction Time to Begin Movement
to one of N targets
Reaction Time (msec)
440
420
400
380
360
340
320
300
1
2
3
4
5
6
7
8
# of possible "targets"
A logarithmic function – as predicted
By Shannon’s Information Theory (1949)
Davachi, Lila et al. (2003)
Meaning, Brain activity, and Memory
Davachi, et al. (2003)
Increases in activation
for Image vs. Read
Davachi, et al. (2003)
Difference in activation
(Image – Read)
for Remember vs. Forget