Cognitive Psychology I Perception, Preconceptions, and Judgment
• Perception - the whole is not equal to the sum of its parts
• Figure and Ground in Perception
• Gestalt Principles
• Our knowledge and preconceptions shape our perceptions
• Illusions
• Perceptual Set
• Judgment under Uncertainty
• Schemas guide our perceptions
• Heuristics in Judgment
Gestalt Psychologists
• They noted that the whole is not equal to the sum of its
parts.
• By this they meant our thoughts and preconceptions shape
what we perceive
• The point is that we do not see exactly what is out there.
Instead our perceptions are shaped by our thoughts.
• Let’s look at some examples.
The Whole is not Equal to the Sum of
Its Parts
The Whole is not Equal to
the Sum of Its Parts II
Figure and Ground in Perception
Gestalt Grouping Principles
Gestalt Principles of Closure and Good Form
Our Knowledge and Preconceptions Shape Our
Perceptions - Muller-Lyer Illusion
Ponzo Illusion
The Ames Room
Perceptual Set - A Demonstration
Schemas and Heuristics
• We need schemas and heuristics to make sense of all the
information that we process.
• Too much information coming in through our senses to
process each piece of information separately.
• We also need schema and heuristics for effect
communication.
• Schema and heuristics allow us to go beyond the
information given.
Schema Allow Us to Go Beyond the Information
Given
The procedure is actually quite simple. First you arrange things into
different groups. Of course, one pile may be sufficient, depending on how
much there is to do. If you have to go somewhere else due to lack of
facilities, that is the next step; otherwise you are pretty well set. It is
important not to overdo things. That is, it is better to do too few things at
once than too many. In the short run this may not seem important but
complications can easily arise. A mistake can be expensive as well. At first
the whole procedure will seem complicated. Soon, however, it will become
just another facet of life. It is difficult to foresee any end to the necessity for
this task in the immediate future, but then one can never tell. After the
procedure is completed one arranges the materials into different groups
again. Eventually they will be used once more and the whole cycle will
then have to be repeated.
Like Illusions, Heuristics Tell Us about how We
Process Information
• Representativeness Heuristic - an example
More Heuristics
• Availability Heuristic - an example
More Heuristics
• Representativeness Heuristic - an example
• Availability Heuristic - an example
• Anchoring and Adjustment - an example
More Heuristics
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Representativeness Heuristic - an example
Availability Heuristic - an example
Anchoring and Adjustment - an example
Risk and Loss Aversion - an example
Focus on University of Waterloo Research
Priming and Time Judgments (Dr. Jennifer Stolz)
• For half of the participants each trial begins with a very brief
prime (for example, bacon).
• For the other participants there are no primes.
• Next two different words come on the screen at almost the
same time. One word is related to the prime (for example,
eggs) the other word is unrelated to the prime (for example,
water).
• When people are not primed they are equally likely to judge
that eggs and water appear first
• When they are primed however they are more likely to think
that eggs appeared before water.
The Fragility of Memory
• Memory Construction - The Construction of Automobile
Destruction
The Fragility of Memory
• Memory Construction - The Construction of Automobile
Destruction
• We tend to remember what we want to remember
• Can we forget what we want to forget?
• It is not so easy
• It is hard to suppress thoughts
• “Recovered Memories”
The Fragility of Memory
• Memory Construction - The Construction of Automobile
Destruction
• We tend to remember what we want to remember
• Can we forget what we want to forget?
• It is not so easy
• It is hard to suppress thoughts
• “Recovered Memories”
• Discerning True from False Memories