Main parts of the body and its functions

1. IV. Sensation and Perception
by:

2. Content:
I. Vision
II. Audition
III. Olfaction and Gustation
IV. Cutaneous Sensitivities
V. Perception and Attention

3. Sensation vs. Perception
Sensation
• Refers to the process of sensing our environment
through touch, taste, sight, sound and smell. This
information sent to our brain in raw forms where
perception comes into play.
• A large amount of information is being sensed at any one
time such as room temperature, brightness of the lights,
someone talking, a distant train, or the smell of
perfume. With all this information coming into our
senses, the majority of our world never gets
recognized. We don’t notice radio waves, x-rays, or the
microscopic parasites crawling on our skin. We don’t
sense all the odors around us or taste every individual
spice in our gourmet dinner. We only sense those things
we are able too since we don’t have the sense of smell
like a bloodhound or the sense of sight like a hawk; our
thresholds are different from these animals and often
even from each other.
Perception
• Is the way we interpret these sensations and
therefore make sense of everything around
us.
• The way we perceive our environment is what
makes us different from other animals and
different from each other. In this section, we
will discuss the various theories on how our
sensation are organized and interpreted, and
therefore, how we make sense of what we
see, hear, taste, touch, and smell.

4. Vision:
• Visible spectrum: Part of the electromagnetic spectrum to which the
eyes respond.
• Lense: Structure in the eye that focuses light rays.
• Photoreceptors: Light-sensitive cells in the eye.
• Cornea: Transparent membrane covering the front
of the eye; bends light rays
• Retina: Light-sensitive layer of cells in the back of
the eye. (Easily damaged from excessive
exposure to light;
Example staring at an eclipse.

5. Vision:
• Researchers have studied vision more thoroughly than the other senses. Because people need sight to
perform most daily activities, the sense of sight has evolved to be highly sophisticated. Vision, however,
would not exist without the presence of light. Light is electromagnetic radiation that travels in the form
of waves. Light is emitted from the sun, stars, fire, and light bulbs. Most other objects just reflect light.
• The color or hue of light depends on its wavelength, the distance between the peaks of its waves.
• The brightness of light is related to intensity or the amount of light an object emits or reflects.
Brightness depends on light wave amplitude, the height of light waves. Brightness is also somewhat
influenced by wavelength. Yellow light tends to look brighter than reds or blues.
• Saturation or colorfulness depends on light complexity, the range of wavelengths in light. The color of
a single wavelength is pure spectral color. Such lights are called fully saturated. Outside a laboratory,
light is rarely pure or of a single wavelength. Light is usually a mixture of several different wavelengths.
The greater number of spectral colors in a light, the lower the saturation. Light of mixed wavelengths
looks duller or paler than pure light.
Wavelength ——> Color
Amplitude ——> Brightness
Complexity ——> Saturation

6. Figure & Ground and Visual Illusion
FIGURE AND GROUND
-identifying a figure from the background.
Figure visual scene that we look at
Ground refers to everything else and forms
the background.
VISUAL ILLUSIONS
-“To see is to believe”, but at times this not so because
perception do fail at times.
-In the study of perception, psychologists have turned to
illusions, in which perceptions are misleading.

7. Audition: The Ear (Hearing)
• The human sense of hearing is attributed to the auditory system, which uses the
ear to collect, amplify, and transduce sound waves into electrical impulses that
allow the brain to perceive and localize sounds.
• The ear can be divided into the outer ear, middle ear, and inner ear, each of
which has a specific function in the process of hearing.
• The outer ear is responsible for the collection and amplification of sound. The air-
filled middle ear transforms sound waves into vibrations, protecting the inner ear
from damage. The fluid-filled inner ear transduces sound vibrations into neural
signals that are sent to the brain for processing.
• The cochlea is the major sensory organ of hearing within the inner ear. Hair cells
within the cochlea perform the transduction of sound waves.
• Humans are capable of estimating a sound's origin through a process called
sound localization, which relies on timing and intensity differences in sound
waves collected by each of our two ears.

8. The Ear
1. The ear is the main sensory organ of the
auditory system. It performs the first
processing of sound and houses all of the
sensory receptors required for hearing.
The ear's three divisions (outer, middle,
and inner) have specialized functions that
combine to allow us to hear.
2. The human auditory system allows the
body to collect and interpret sound
waves into meaningful messages. The
main sensory organ responsible for the
ability to hear is the ear, which can be
broken down into the outer ear, middle
ear, and inner ear. The inner ear contains
the receptor cells necessary for both
hearing and equilibrium maintenance.
Human beings also have the special
ability of being able to estimate where
sounds originate from, commonly called
sound localization

9. AUDITION:
• Hearing, or audition, depends on the presence
of sound waves, which travel much more
slowly than light waves. Sound waves are
changes in pressure generated by vibrating
molecules. The physical characteristics of
sound waves influence the three psychological
features of sound: loudness, pitch, and timbre.
• Loudness depends on the amplitude, or
height, of sound waves. The greater the
amplitude, the louder the sound perceived.
Amplitude is measured in decibels. The
absolute threshold of human hearing is
defined as 0 decibels. Loudness doubles with
every 10-decibel increase in amplitude.

10. Olfaction and Gustation:
• Sensory system for the detection
of chemicals (chemical senses).
• Olfaction (smell) detects
chemicals in the air.
• Gustation detects chemicals
dissolved in a solution (saliva
helps to dissolve the chemicals.)
Gustation:

12. Olfaction:
The sense of olfaction is complex.
Odor perception is influenced by
many factors unique to each
individual as well as external
environmental factors. The basis of
odor perception is the contact
between chemical molecules,
mainly in the gaseous state, which
can be detected by the olfactory
epithelium.

13. Sensations on the skin are detected by cutaneous receptors:
Mechanoreceptors - detect light pressure (e.g., caress), vibration, and texture,
Nocicreceptors - detect strong pressure (e.g., pain), and
Thermoreceptors - detect temperature (hot or cold).
For example, if your dog lightly presses its nose on your leg, mechanoreceptors in your skin will sense
the smooth texture of your dog’s nose whereas thermoreceptors will detect its coldness. When a dog
bites someone, nociceptors detect the sharp pressure. Astereognosis is the inability to identify an object
by touch.
Cutaneous Sensitivities:
What are Cutaneous Sensitivities?
A group of Skin Senses:
1. PRESSURE
2. PAIN
3. COLD
4. WARMTH

28. Perception and Attention:

35. Thank you…

36. Leader: Queen Elizabeth Vega
Members:
Ma. Cristina Genoveso
Ruel T. Baltazar
Anthony Glaine Albay
Alexandra Kyle Rubiales
John Ace De Leon