1.
Perception

2.
Perception
What enables you to recognize these people?

3.
• Perception of the world relies on more than just
the information arriving at sensory receptors
• Ability to transform and interpret sensory
information helps in recognition.
• Something more is needed to make a stimulus
meaningful and interesting.

4.
Perception
• The process by which we become
aware of objects and events in the
external world.
• The process of making sense of the
world around us.
• Usually we spend more energy
Where does the
defending our own position than triangle begin?
understanding others.

5.
Sensation and Perception
• Sensation is the immediate
response of our sensory
receptors to basic stimuli.
• Perception is the process by
which sensations are selected,
organized, and interpreted.

6.
Perceptual Process
We receive external
stimuli through
our five senses

7.
Influences on Perception
• Physiological (biological,
neurological) Influences
• Senses, age, health, fatigue,
hunger, biological cycles
• Social Influences
• Cultural Differences
• Nonverbal behaviors, odors,
speech, silence, space
• Social Roles
• Sex roles, gender roles,
occupational roles
• Self-Concept
• Self-esteem, locus of control,
attribution (attaching meaning to
behavior)

8.
Perceptual Process
Stage 1: Selection
• Life is a process of selecting information/data
• We are confronted with millions of pieces of
stimuli each day
• Sensation provides a first-pass
representation of the basic facts of the visual
field.

9.
Stage 2: Perceptual Organization
• To eliminate the chaos of life and help make sense of
the world, we simplify and reduce our world
• We put our ―selected‖ data in cognitive ―folders‖
• An internal representation of an object is formed and
a percept of the external stimulus is developed.
• Estimates are based on mental computations that
integrate your past knowledge with the present
evidence received from your senses and with the
stimulus within its perceptual context awareness.

10.
How many Fs?

11.
Stage 3
Interpretation/Comprehension
• Next, we have to Evaluate the data in our folders.
Identification and recognition assigns meaning to
percepts.
• What does the object look like?‘ changes to a
question of identification — ‗‗What is this object?‘‘
• — and to a question of recognition—‗‗What is the
object‘s function?‘‘

12.
The Proximal and Distal Stimulus
• Retinal image is two-dimensional,
whereas the environment is three-
dimensional
• Perception can be thought of as the
process of determining the distal
stimulus from information contained in
the proximal stimulus.
Interpreting retinal
images.
A. Physical object
(distal stimulus)
B. Optical image
(proximal stimulus)

13.
Reality, Ambiguity, and Illusions
• Single image at the sensory level can result
in multiple interpretations at the perceptual
and identification levels.
• Ambiguous figures have perceptual
instability.
• When your perceptual systems actually
deceive you into experiencing a stimulus
pattern in a manner that is demonstrably
incorrect, you are experiencing an illusion.

14.
Ambiguity in the perceptual organization stage
Ambiguity in the recognition stage

15.
Perception Theories
• Helmholtz‘s Classical Theory -
• By using prior knowledge of the
environment, an observer makes
hypotheses, or inferences, about the way
things really are.
• The Gestalt Approach -
• Psychological phenomena could be
understood only when viewed as organized,
structured wholes and not when broken
down into primitive perceptual elements.

16.
• Gibson‘s Ecological Optics -
• Instead of trying to understand perception as
a result of an organism‘s structure, Gibson
suggested that it could be better understood
through an analysis of the immediately
surrounding environment

17.
Attention
• Attention is the extent to which processing
activity is devoted to a particular stimulus
• Focus of attention determine the types o
information most readily available to
perceptual processes
• Selective Attention
• Goal directed selection – Choices that we
make as a function of our own goals.
• Stimulus Driven capture - When features of
the stimuli capture attention, independent of
goals of perceiver.