Cognitive process, perception

1. PERCEPTION
By Amit Newton
Tutor Nishat College of nursing
HOD Psychiatric Nursing Dept.

11. INTRODUCTION
• When our sensory-organs comes in contact with the world
and are stimulated by the external stimuli and receive the
sensations it result in perception.
• Sensation is the initial response of an individual to the
stimuli.
• Perception is the interpretation of sensory stimuli which
reach the sense organs and the brain.

12. PERCEPTION
What is Perception
 How we view and interpret the events and situations in the world
about us.
What is it Important
 Because people’s behavior is based on their perception of what
reality is, not on reality itself.

13. Definition
Perception is the experience of object, events or
relationships obtained by extracting the information from
and interpreting the sensations.
(OR)
A process by which individuals organize and interpret their
sensory impressions in order to give meaning to their
environment.

14. Process of perception
Perception is the process by which we discriminate
among the stimuli and interpret their meanings.
Eg: when we hear a sound we are able to identify it as being
produced by a car or a bus. Perception gives meaning to sensation.

15. Process of perception
Perception is the process by which we discriminate
among the stimuli and interpret their meanings.
Eg: when we hear a sound we are able to identify it as being
produced by a car or a bus. Perception gives meaning to sensation.

16. Perception
Perception is a process by which individuals organize
and interpret their sensory impressions in order to
give meaning to their environment.

17. Principles Perception

18. Principle of figure ground relationship
A figure is perceived in relationship to its background. The perception
of the object or figure in terms of color, size, shape and intensity, etc
depends upon the figure-ground relationship.

19. Principle of closure
While confronting incomplete pattern
one tends to complete or close a
meaningful whole.

20. Principle of grouping
It refers to a tendency to perceive stimuli
in some organized meaningful patterns by
grouping them on some solid basis like
similarity, proximity and continuity.

21. Principle of simplicity
We perceive the simplest possible pattern
because they enable the perceiver to
perceive the whole from some of its parts.

23. Principle of contour
A contour is said to be a boundary
between a figure and its ground. The
degree of the quality of this contour
separating the figure from the
ground is responsible for enabling us
to organize stimuli or objects into
meaningful patterns.

24. Principle
of
contour

25. Principle of context
Perceptual organization is also governed by the principle of context, i.e.
an examiner may award higher marks to the same answer book in a
pleasant context than in an unpleasant one

26. Principles of contrast
• Perceptual organization is very
much affected through contrast
effects as the stimuli that are in
sharp contrast to nearby stimuli
may draw our maximum
attention and carry different
perceptual affects.

27. Principle of adaptability
The perceptual organization for some
stimuli depends upon the adaptability
of the perceiver to perceive similar
stimuli. An individual who adapts
himself to work before an intense
bright light will perceive normal
sunlight as quite dim.

28. Factors affecting perception
• Sense organs
• Brain
• Memory images of the past experiences
• Personal interest and mind set
• Acquired interest
• Needs and Desires

29. Errors in perception
• Errors in perception also called Sensory
deceptions- these can be divided into
illusion which are misinterpretations of
stimuli arising from an external object, and
hallucinations , which are perceptions
without an adequate external stimulus.

30. Illusion
• In illusions, stimuli from a perceived object are combined with a
mental image to produce a false perception
Types
Three types of illusion are described ( Sims, 2003)
 Completion illusions
 Affective illusion
 Pareidolia

31. Hallucinations
• Jaspers suggested- “ a false perception which is not a sensory
distortion of misinterpretation, but which occurs at the same time as
real perception.”
• Hallucination are imaginary perceptions in which one sees or hears
something that is not seen or heard by others around him
• Eg. An alcoholic may see “Pink elephants”, a paranoid schizophrenia may hear voices,
experiencing foul odors in absence of common in mentally ill people.
• Hallucinations are visual, auditory, kinesthetic, olfactory and
gustatory.

33. Causes of inaccurate perception
 Defective function of sense organs
 Inadequate stimulus
 Too many stimuli at one time
 Poor health
 Limited attention
 Figure merges in the ground
 Guidance- (Perception is inaccurate when we do not know what
should be perceived)