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Republic of the Philippines
EULOGIO “AMANG” RODRIGUEZ
INSTITUTE OF SCIENCE AND TECHNOLOGY
Cavite Campus
General Mariano Alvarez, Cavite
CULPSYCH: SENSATION AND PERCEPTION
Objectives:
At the end of this chapter the students will be able:
 Attain an understanding on sensation; be familiarize with different sense organs which are
responsible for sensory experience.
 Identify the different receptor organs and their functions
 Understand the nature of perception and identify its goals
 Determine the factors that may affect one’s perception and be able to understand the
principle governing perception
 Differentiate and evaluate the types of extra sensory perception
Definition of terms:
Sensation. The fundamental awareness and mental process by which aroused through the
stimulation of the sense organ
Perception. Giving of interpretation or meaning to the stimulus by the brain to respond
Stimulus. Any form of energy that can cause awareness or change in consciousness or
anything in which arouses the sense organ
How to acquire sensory awareness or experience?
1. First essential condition: stimulation of sense organ
2. There should be receptor organ
3. The presence of the receptor cell
4. Transduction- a process in which sense organ change/transform physical energy into electric
signals that becomes neural impulses
Different ways on how a sensory experience is measured
1. Psychophysics. It is a special procedure introducing the link between physical stimuli and
sensation
2. Absolute threshold. The minimum intensity a stimulus must have in order to produce a
sensation
3. Difference threshold or Just Noticeable Difference (JND). The minimum change that a
stimulus must undergo before the change can reliably detected
4. Weber’s law- the rule that the larger or stronger the stimulus the larger the change required
an observer to notice any difference
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Overview of Sensation
Type of
Sensation
VISION
AUDITION
OLFACTION
GUSTATION
CUTANEOUS
Stimulus
Receptor
Light waves
eyes
Sound
waves
Gaseous
substance
Taste
ears
nose
tongue
Thermal and
mechanical
stimulation
Skin
Areas in
the brain
Occipital
lobe
Temporal
lobe
Parietal
lobe
Parietal
lobe
Parietal
lobe
AUDITION
EARS
Stimulus: Sound waves
Receptors: Auditory receptors(hair cells)
Parts of the ear
 Outer Ear
External ear/Pinna
Auditory meatus
Tympanic membrane /Eardrum
 Middle Ear
The three bony prominence that acts as a lever
that greatly amplify the vibration
Malleus (Hammer)
Incus (Anvil)
Stapes (Stirrups)
 Inner ear Cochlea- involves in hearing
Vestibule-involves in balance
GUSTATION
TONGUE
Stimuli: chemical substance soluble to saliva
Receptors: taste buds
Flavor: combination of taste and smell
OLFACTION
NOSE
Stimuli: chemical or gaseous substance carried by the air
Receptors: olfactory cells
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Types of sensation
Hue, brightness, saturation
Pitch, loudness, tempo
Putrid, smoky, spicy, flowery,
resinous
Bitter, sweet, sour, salt
Pain, pressure warm, cold
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CUTANEOUS
SKIN
Stimuli: pressure, pain and temperature
Receptors: hair receptors
This are free nerve endings in the middle layer of the
skin that is wrapped around the base of each hair
follicle
VISION
EYES
Stimuli- light waves
Receptor- Rod and cones
Parts of the Eye
 Retina- a light sensitive membrane in the lining in
the inner eyeball that contains layers of bipolar
cells and photo receptor cells called rods and
cones
 Sclera- white elastic covering of the eye
 Cornea- a transparent bulge that can be located
in the front of the eyes which the light wave
passes
 Pupil- are dark circular aperture in the center of
the iris which receives light
 Lens- it focuses the light ray entering to the pupil
to form an image to the retina
 Optic nerve- bundle of fibers which is connected
to the retina and the brain
Visual Defects
 Nearsightedness (MYOPIA) - The eyeball is too long. The image comes into focus
slightly in front of the retina.
 Farsightedness (HYPEROPIA) – The eyeball is too short for close vision, the image
comes into focus behind the retina.
 Old sightedness (PRESBYOPIA) – special condition of farsightedness common among
people 40 years old and above which is brought about by hardening of the lens.
 Double vision (DIPLOPIA) – It is caused by, muscular imbalance which permits light
reflected from one point to fall on non-corresponding receptor in the two retinas.
 Astigmatism – the cornea becomes irregular causing distortion of the image in the retina.
Color blindness or color vision deficiency- is the inability or decreased ability to see color, or
perceive color differences, under normal lighting conditions.
2 types
 Dichromatic- has to or more primary color that are functioning
 Achromatic- has no cones in the retina. He or she will the world without color or black
and white
The test that is use to check for color blindness is the Ishihara Test
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Visual acuity- the individual’s ability to discriminate the details of an object
It refers to the clearness and sharpness of vision
It can be measured by Snellen chart
A standard normal vision is 20/20 (perfect vision) it means that he can read 20 ft. the letter that
an average person can read at a distance of 20 ft.
PART II: PERCEPTION
Perception – is a process of interpreting sensation to make them significant or meaningful. It is
defined as interpretation of stimulus
Goal of perception
Recognition- the way of identifying what the object is
Localization- the way of determining where the object is
Perceptual constancy-it refers to the constant appearance of an object
Principles of perceptual organization
We have various ways of organizing different stimuli we encounter form our environment
Gestalt psychologist emphasize how we perceive the configuration or wholeness of an object
They proposed a number of Principles of psychology
A. Figure and ground
e have the tendency to look for an object which consist of two or more regions based from the
region that appears to be more interesting and appealing to our sight. This becomes the figure
because it is our object of interest and the other serves as the ground.
Figure- it is usually at the front or center, or on top of what we perceived as the ground. It
possesses shape, consistency and oneness.
Ground- no definite shape
Ex. Vase/Urn and the 2 silhouette background f 2 faces
Contour provides the boundary between the figure and the ground. It is also a boundary to a
shape however it is not a considered as a shape
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B. Gestalt Grouping
Grouping is when a certain element or objects are put together forming a whole pattern
according to the following principles or based on the following laws




Law of proximity
Law of similarity
Law of continuity
Law of closure
Law of proximity- state that elements that are near or close to each other are group together
Law of similarity- states that stimuli that are similar are tend to be group together
Law of continuity-state that we usually link individual elements so that they form a contour line
or pattern that make sense to us
Law of closure- state that any stimuli that suggest a continuous closed contours is perceived
as figure
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C. Camouflage- this principle which means as the ability to blend with colors in the environment
enable them to adapt and adjust.
D. Figural after effects- the eye especially the part of the retina if stimulated for a long period
of time may see a distorted object
E. Perceptual depth- the ability to perceive objects in terms of distance and depth


Monocular cues
 Relative size
 Relative height
 linear perspective
 interposition
Binocular cues
 retinal disparity
 convergence
MONOCULAR CUES
Relative size- if an image contains an array of similar objects that differ in size. People interpret
the smaller objects as being farther way.
Relative height- among similar objects, those that appear higher are being perceived as farther
away
Linear perspective- when parallel lines appear to converge, they perceive as vanishing in the
distance.
Interposition- if an object is partly covered by another, the front object is being perceived as
nearer
BINOCULAR CUES
Binocular or retinal disparity
Each eye looks at the world from a slightly different viewpoint and so each retina receives a
slightly different image. The brain detects the difference and uses it as a cue to distance
It refers to a binocular depth cue that depends on the distance between the eyes. Because of
their different positions, each eye receives a slightly different image.
Convergence
The nearer an object is, the more your eyes turn inward to see it. Information passes from the eye
muscles to the brain helping us to gather information on distance.
It refers to a binocular cue for depth perception based on signal sent from muscles that turn the
eyes. To focus on near or approaching objects, these muscles turn the eyes inward, toward the
nose. The brain uses the signal sent by these muscles to determine the distance of the object.
Errors in perception
Inability to identify and distinguish object accurately because of physiological and psychological
situation
Illusion- a distortion of senses, revealing how the brain normally organized and interprets
sensory stimulation
Hallucination- false notion or perception which arises from inner mental factor
Delusion- refers to the mistaken belief that object and things exists, abnormal individual usually
perceived things not senses by primary individuals
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EXAMPLES OF VISUAL/ PERCEPTUAL ILUSION
Are the horizontal lines parallel
Eskimo?
or do they slope?
Ignoring the arrow head which
horizontal line is longer?
Young lady or old woman?
Indian or
Rabbit or duck?
EXTRA SENSORY PERCEPTION
“Outside normal sensory process”
 This is a perception without the mediation of sensory organ stimulation
 They can sometimes experience unexplainable phenomenon
Telepathy-it refers to the transfer of thought between individuals usually defined as thought
transference from one person to another
Clairvoyance “clear sight” it refers to the ability to see without making use of the sense of sight
Precognition-the ability to perceive or accurately predict future events
Psycho kinesis/Telekinesis- the ability to move things by willing them to move mentally without
touching them physically
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