Chapter 1
Everyday examples of cognition: perception, attention, pattern recognition,
memory, recognition, recall, reasoning, problem solving, decision-making, language,
etc.
Philosophical roots of cognitive psychology:
Empiricism - Locke (tabula rasa), associationism, principle of contiguity
& importance of experience.
Rationalism - Kant (categories of thought), nativism, & active mental
processes.
Early Experimental Psychology:
Voluntarism - Wundt 1st experimental psychology lab in 1879 at University
of Leipzig, Germany;
Wundt used basic experimental psychophysical techniques.
Structuralism - Titchener searched for a mental table of elements; his
primary research tool was introspection.
Functionalism - James wrote Principles of Psychology (1st psychology
textbook); influenced by evolutionary
theory and the purpose of behavior; more broad view than Structuralism - studied
abnormality,
applications, animals, etc.
Behaviorism - classical conditioning (Pavlov), instrumental conditioning
(Thorndike), operant
conditioning (Skinner), & Tolman (purposive behaviorism; cognitive maps;
learning without
reinforcement).
Gestalt Psychology - Law of Prägnanz & principles of perceptual
grouping; the whole is greater than the sum
of the parts.
Genetic Epistemology - Piaget & cognitive development; children in
different stages of cognitive development
actually think differently (i.e., they have different cognitive structures).
Individual Differences - evolutionary theory; Galton and intelligence.
The "Cognitive Revolution" influenced by a number of trends:
Human-factors engineering (the person-machine system; ergonomics)
Communication systems theory/communications engineering (limited-capacity
processors)
Linguistics (Chomsky & the language acquisition device - LAD)
Localization of function (neurology)
Computer as metaphor for the human mind (artificial intelligence)
Trends in Cognitive Psychology: cognitive science (interdisciplinary
field) & cognitive neuropsychology (often
study brain damaged people & their cognitive deficits)
Research Methods in Cognitive Psychology
Ecological validity/external validity versus experimental control/internal
validity.
Experimental Designs: between-subjects versus within-subjects.
Paradigms of Cognitive Psychology
Information-processing approach - tends to use the computer metaphor
& sequential stages of cognitive
processing; know the information-processing model on page 29 of textbook.
Connectionist approach (neural networks) - emphasizes parallel processing
in networks of nodes
(perhaps similar to how actual neurons work); know connectionist model on page
31 of textbook.
Evolutionary approach - emphasizes the function of cognitive abilities
in survival & reproduction; examples
include mating strategies and suspicion/jealousy.
Ecological approach - emphasizes natural contexts/settings in which cognitive
activities occur.
Chapter 2
4 reasons why cognitive psychologists should be interested in perception (from
lecture): (1) perceptions are one of the primary reasons/causes of perceptions,
(2) cognitive processes can influence perceptions, (3) knowledge of perception
can help an understanding of memory, (4) there is no internal cognitive reality
without input from stimuli in the world.
What is the distinction between sensation & perception?
Distal stimulus, proximal stimulus, percept & pattern recognition.
Gestalt approaches to perception:
Form perception (figure/ground distinction) - much of perception is automatic
(without conscious awareness).
Subjective/illusory contours
Law of Prägnanz - overarching Gestalt law for perceptual organization.
Gestalt Principles of perceptual organization
Principle of proximity/nearness
Principle of similarity
Principle of good continuation
Principle of closure
Principle of common fate
Principle of inclusiveness
Problems with Gestalt approach: describes but does not explain underlying
cognitive processes, Law of Prägnanz can be circular (no clear definition
of "simple")
Bottom-up (data-driven) theories of perception and pattern recognition:
Template Matching - templates must match perfectly, many machines/computers
work this way. Problems
with template matching: impossibly large number of templates would have to be
stored in memory (ex.
"grandmother cell"), doesn't explain how we recognize new objects
or how we form new templates,
doesn't explain how we perceive different stimuli as being the same thing (A,
a, A, etc.).
Featural Analysis - first subpatterns or features are detected, then
these features are combined into larger
objects (fits some neurophysiological evidence - Hubel &Wiesel's simple
cells), is also consistent with
language being broken down into words and letters. However, what exactly is
a feature? 2 feature
approaches:
(1) Recognition by Components Theory - geons (geometric icons; three-dimensional
features); what
research evidence supports RBC theory?
(2) Pandemonium Model - features (lines, angles, curves) used to recognize
letters; 3 levels or stages
of processing in this model: feature demons, cognitive demons, & decision
demons; the
different "demons" may represent nodes or neurons with louder "shouting"
representing a
stronger neural connection between the demons.
Problems with featural analysis theories: no good/clear definition of what can
be a feature; if
different kinds of features for different kinds of objects, then a huge number
of features to store
in memory (and how could we quickly search all those features and quickly recognize
objects);
if different features for different kinds of objects, then how do we know which
features to search
for the different kinds of objects?
Prototype Matching - the best or ideal example of something; incoming
sensory information does not have to
perfectly match the prototype in order for recognition to take place. What is
the experimental evidence
that supports the existence of prototypes (Posner & Keele, 1968, & Cabeza
et al., 1999)? Two theories
concerning prototypes:
(1) central tendency model - prototypes are formed using the average (arithmetic
mean) of a
set of examples.
(2) attribute frequency model - prototypes are formed using the mode
(most frequently
experienced) attributes from examples that one experiences.
Top-down (theory-driven or conceptually-driven) theories of perception
& pattern recognition:
Contextual & expectation effects (examples on pages 62-63 of textbook)
Marr's model of perception with 3 levels/kinds of representations (called
sketches):
· primal sketch (two-dimensional image) - detection of boundaries,
relative brightness, etc.
· 2 ½-D sketch (two-and-a-half dimensional) - uses/adds
more depth cues (like shading, texture,
etc.) to identify where objects are in relation to the observer.
· 3-D sketch (full three-dimensional image) - this involves top-down
processes, the information
from previous stages is combined with prior knowledge & expectations to
form
final/complete perception.
The first two sketches (primal & 2 ½-D) involve bottom-up processes,
whereas the third sketch (3-D)
involves top-down processes.
Perceptual Learning - changes in perception that occur as a function
of practice or experience; experts
perceptions of stimuli are different from the perceptions of novices; Gibson
& Gibson (1955)
demonstration of this phenomenon (figure 2-20, page 65).
Change Blindness - inability to detect changes to an object or scene;
studies of change blindness (pp. 67-69).
Why do people fail to notice changes? Visual perceptions may be mainly automatic
processes that
represent the general meaning (i.e., gist) of what is happening. In other words,
the focus is on the
meaning (top-down process) rather than with the specific details (bottom-up
process). An implication is
that our visual percepts are not precise copies of the actual visual world.
Practiced Perceivers (i.e., experts)
Word superiority effect (word advantage) - the phenomenon that single
letters are more quickly
identified in the context of words (than when alone or when placed into a pattern
with other
random letters).
McClelland & Rumelhart's (1981) connectionist model of letter perception
- can explain the word
superiority effect through the concept of spreading activation; the neural activation
from the
seeing the word spreads from that word node down to the letter nodes, priming
a quicker
reaction to the letters that are in that word.
Neuropsychological Study of Word Perception: researchers found that different
areas of the cortex were activated
when participants were viewing word & pseudowords versus random letter strings
& false fonts. There was
more neural activity in the left cortex (the left hemisphere) for the words
& pseudowords, and also more
activation outside of the primary visual cortex (outside the occipital lobe)
for the words & pseudowords
(perhaps indicating some semantic processing).
Direct Perception (previous theories in this chapter can be thought of
as constructivist approaches to perception, however, direct perception views
perception differently):
Direct perception - Information in the world is "picked up on" by
the cognitive processor without much
construction of internal representations or inferences. The emphasis is on direct
acquisition of
information from the environmental stimuli.
Optic flow
Affordances - the purposes of objects, which dictate the acts & behaviors
that are appropriate in
response to these stimuli.
Visual Agnosias - impairments in the ability to interpret visual information.
Apperceptive agnosia, associative agnosia & prosopagnosia.