THE COGNITIVE
APPROACH
TYPES OF PROCESSING
Adapted from
http://psiexp.ss.udi.edu by E.Day
Areas of Study

Cognition is about internal processes that are often
unobservable, e.g.:
Perception, Attention, Memory, Visual Imagery, Language,
Concept Learning, Reasoning
?

Need converging evidence from different perspectives to really
understand cognitive processes
Adapted from
http://psiexp.ss.udi.edu by E.Day
Information Processing




Information processing models resemble
processing in computers – made cognitive
psychology popular
Information made available by the environment
is processed by a series of processing systems
Processing system is a set of processes that
work together to accomplish a type of task, using
and producing representations as appropriate
The major goal of research is to specify these
processes and representations
Adapted from
http://psiexp.ss.udi.edu by E.Day
Types of Processing


Bottom-up processing. Processing directly
affected by the stimulus input is usually
described as stimulus-driven or
bottom-up processing.
Top-down processing Processing. Processing
is influenced by past experience and
expectations . These influences constitute
top-down or conceptually driven
processing.
Adapted from
http://psiexp.ss.udi.edu by E.Day
Types of Processing


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Serial processing In serial processing, it is argues that
each cognitive process is accessed in turn. (i.e. one process is
completed before the next starts)
Parallel processing A very different possibility is that some or
all of the processes involved in a cognitive task occur at the
same time. This is known as parallel processing.
Parallel Distributed Processing (PDP) One problem with
parallel processing is the idea that these processes operate
simultaneously but independently of each other. In parallel
distributed processing (PDP), cognitive processes operate at the
same time and connections between them also influence the
final outcome. This approach is also referred to as
Connectionism.
Adapted from
http://psiexp.ss.udi.edu by E.Day
Bottom Up
Processing : An
early version of
the informationprocessing
approach
 purely bottom
up or stimulusdriven
Adapted from
http://psiexp.ss.udi.edu by E.Day
A Demonstration of Top-Down
Processing
Adapted from
http://psiexp.ss.udi.edu by E.Day
Top-down processing: perception affected by knowledge of
world
Why do we seem to have a fairly robust interpretation of which shapes
are concave and convex when the perceptual information is perfectly
ambiguous? -> perception affected by knowledge
Adapted from
http://psiexp.ss.udi.edu by E.Day
(Kleffner & Ramachandran, ’92)
Sound Induced Illusory
Flashes

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Example of parallel and interactive
processing: visual perception affected
by auditory perception
http://www.cns.atr.jp/~kmtn/soundIndu
cedIllusoryFlash2/
Adapted from
http://psiexp.ss.udi.edu by E.Day
Top-down
processing
Later stages of
processing affect
earlier stages
 can explain effects
of Knowledge,
memory,
expectations and
context
Adapted from
http://psiexp.ss.udi.edu by E.Day
Serial, Parallel and PDP
Processing

To illustrate the differences between serial,
parallel and parallel distributed processing,
consider the Sternberg task

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Goal: what steps are involved in comparing
information to memory? How long do these steps
take?
Task:
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give subjects memory sets. E.g. 3 9 7
Probe memory with targets and foil digits: 9 =
“yes”, 6=“no”. Measure reaction time.
Vary the size of these memory sets
Adapted from
http://psiexp.ss.udi.edu by E.Day
Typical Sternberg Results


Plot reaction time as
function of memory set
size and type of trial
(targets/foils)
What are the
implications of seeing a
linear increase in
reaction time as a
function of memory
set?
Adapted from
http://psiexp.ss.udi.edu by E.Day
A serial information processing
model for Sternberg task
9
Perceive
Stimulus
Is it a
3?
Is it a
9?
Is it a
7?
Make
Decision
This serial information processing model predicts a linear increase
Adapted from
http://psiexp.ss.udi.edu by E.Day
yes
A parallel information processing
model for Sternberg task
Is it a
3?
9
Perceive
Stimulus
Is it a
9?
Make
Decision
yes
Is it a
7?
This parallel information processing model also predicts a linear increase
Adapted from
http://psiexp.ss.udi.edu by E.Day
A parallel distributed information processing
model for Sternberg task
Is it a
3?
9
Perceive
Stimulus
Is it a
9?
Make
Decision
yes
Is it a
7?
What is the difference between this model and the Parallel model
of processing?????
Adapted from
http://psiexp.ss.udi.edu by E.Day