Student Powerpoint PSYCH 1 Introduction in Psychology

1. Sensation
and
Perception

2. GROUP 4 (CHAPTER 6)
MEMBERS:
Iris Mae Genigani
Janna Andrea Generalo
Bless Garcenila
Cristell Joy Garcia

3. Table of contents
Introduction
1. Sensing the World: Some basic Principles
2. Thresholds
3. Sensory Adaptation

4. Sensing the
world: Some
basic principle
Sensation – the
process by which
our receptors and
nervous system
receive and
represent stimulus
energy from our
environment.
Perception- the
process of organizing
and interpreting
sensory information,
enabling us to
recognize meaningful
objects and events.
Nature’s sensory gift suit each
recipient’s needs. They enable each
organism to obtain essential
information. Consider:
• A frog, which feeds on flying
insects , has eyes with receptor
cells that fire only in response to
small, dark moving objects. A
frog could starve to death knee
deep in motionless flies. But let
one zoom by the frog’s “bug
detector” cells snap awake.
Bottom-up Processing
- Analysis that begins with the
sensory receptors and works up
to the brains integration of
sensory information.
Top-down Processing
- Information processing
guided by higher level-
mental process as when
we construct perceptions
drowning in our
experience and
expectations

5. THRESHOLDS PSYCHOPHSYICS
- The study of relationship between the physical
characteristics of stimuli, such as their intensity and our
psychological of them.
Absolute Threshold
- The minimum stimulation needed to detect a
particular stimulus so percent of the time.
Signal Detection Theory
- A theory predicting how and when we detect the
presence of a faint stimulus (signal) amid
background stimulation (noise).
Subliminal
- Below one’s absolute threshold for conscious
awareness.
Priming
- The activation often unconsciously of certain
association, thus predisposing one’s perception,
memory or response
Different Threshold
- The minimum difference between two stimuli required for detection so
percent of time.
Weber’s Law
- The principle that, to be perceived as different, two stimuli must differ by a
constant minimum percentage ( rather that a constant amount).

6. VISION
Lens-the transparent structure behind the
pupil that changes shape to help focus
image on the retina.
Retina-the light-sensitive inner suface of
the eye,containing the receptor rods and
cones plus layer of neurons that begin the
processing of visual information.
• The Eye
Pupil-the adjustable opening in the
center of the eye through which light
enters.
Iris -a ring of muscle tissue that
forms the colored portion of the eye
around the pupil and controls the
size of the pupil opening.
• Accomodation-the process by which the eyes lens
changes shape to focus near or far objects on the retina.
• Rods-retina receptors cells that are concentrated near
the center of the retina and that function in daylight or
in well-lit conditions.

7. Optic nerve-the point at which the optic nerve
leaves the eye ,creating a "blind" spot because no
receptor cells are beated there.
Fovea-The central focal point in the retina,around
which the eye's cones cluster.

8. VISUAL INFORMATUON PROCESSING
Feature Detector-nerve cells in the brain that respond to specific features of the stimulus,such as
shape,angle or movement.
Parallel Processing-the processing of many aspects of a problem simultaneously,the brains natural
mode of information processing of many functions,including vision.
Young-Helmholtz-Trichomatic (three color) Theory- the theory that the retina contains three
different color receptors one most sensitive to red,one to green,one to blue-which,when stimulated
combination,can produce the perception of any color.
Opponent Process theory- the theory that opposing retinal processes (red-green,yellow-blue,white-
black)enable color vision.For example some cells are stimulated by green and inhibited by;others are
stimulated by red and inhibited by green.

9. VISION
Transduction- conversion of one form of energy into another
Wavelength- the distance from the peak of one light or sound wave to the peak of the next
Electromagnetic wavelengths vary.
Hue- The dimension of color that is determined by the wavelength of hight;what we know as the
color names blue,green,and so forth.
Intensity- the amount of energy in a light or sound wave,which light enters.

10. HEARING
THE STIMULUS INPUT: SOUND WAVES
HEARING
- Our audition, or
hearing, is highly
adaptive. We hear a
wide range of sounds,
but we hear best those
sounds with frequencies
in a range corresponding
to that human voice.
Also we are acutely
sensitive to faint sounds,
an obvious boon for our
ancestors’ survival when
hunting or being
hunted, or for detecting
a child whimper.
-The ears then transform the vibrating air into nerve
impulses, which our brain decodes sounds. Strength
or amplitude, of sound waves determine their
loudness. Waves also vary in length, and therefore in
frequency. Their frequency determines the pitch we
experience: Long waves have low frequency- and low
pitch. Short waves have high frequency and high
pitch. The absolute threshold for hearing is arbitrarily
defined as zero decibels. The correspond of every 10
decibels to a tenfold is increase in sound intensity.
Normal conversation has (60 decibels) is 10,000
times more intense than a 20-decibel whisper, and
the temporarily tolerable 100- decibel passing
subway train is 10 billion times more intense than
the faintest detectable sound

11. THE EAR
THE EAR
How does the ear transform sound energy into neural
message?
-To hear, we must somehow convert sound waves into
neural activity. Human ear accomplishes this feat through
an intricate mechanical chain reaction. The visible outer ear
channels the sound waves through the auditory canal to the
eardrum, a tight membrane that vibrates with the waves.
3 PARTS OF EAR
Middle ear- transmits eardrum’s vibration through a piston
made of three tiny bones to the cochlea.
• *the hammer
• *anvil
• *stirrup
Inner ear- the innermost part of ear, containing;
• *the cochlea
• *semicircular canals
• *vestibular sacs
Outer ear- consists the visible portion on the side of the
head, known as the pinna, and the external auditory canal
(ear canal).
• Helix
• Antihelix
• Antitragus
• Fossa
• Auditory canal
• Tragus
• Concha
• Lobule
- The incoming vibrations cause
the cochlea’s membrane (the oval
window) to vibrate, jostling the fluid
that fills the tube.

12. THE EAR

13. Hair cells
How we transform sound waves into
nerve impulses that our brain interprets?
- Outer ear funnels sound waves to the
eardrum. The bones of the middle ear
amplify and relay the eardrum’s
vibrations through the oval window
into the fluid-filled cochlea. Hair cell
movements trigger impulses at the
base of the nerve cells, whose fiber
converge to form the auditory nerve,
which send neural messages to the
thalamus and on the auditory cortex.
- Triggers impulses in the adjacent
nerve cells, whose axons converge to
form the auditory nerve, which sends
neural messages ( via the thalamus) to
the temporal lobe’s auditory cortex. The
most intriguing part of the hearing
process is the hair cells. Howard Hughes
Medical Institute (2008) report on these
“quivering bundles that let us hear”
marvels at their “extreme sensitivity and
extreme speed”. Cochlea has 16,000 of
them, which sound like a lot until we
compare that with an eye’s 130 million or
so photoreceptors. Damage to hair cells
accounts for the most hearing loss.
- When vibrating in response to
sound, the hair cells shown here lining the
cochlea produce an electrical signal .

14. Perceiving Loudness
How do we detect loudness?
-The intensity of a hair cell’s response.
Rather, a soft, pure tone activates only
few hair cells at turned to its frequency.
Given louder sounds, its neighbor hair
cells also respond. The brain can
interpret loudness from the number of
activated hair cells. The hair cell can
respond to a loud sound even it will loss
sensitivity. Really loud sounds may
seem loud both to people with hearing
loss and to those with normal hearing.
Perceiving Pitch
What theories help us understand pitch person
- Hermann von Helmholtz’s place theory
presumes that we hear different pitches
because different sound waves trigger activity at
different places along the cochlea’s basilar
membrane . brain determines a sound’s pitch by
recognizing the specific place (on the
membrane) that is generating the neural signal.
Nobel laureate-to-be George von Bekesy (1957)
discovered that the cochlea vibrated, rather like
a shaken bedsheet, in response to sound. The
problem with place theory. It can explain how
we hear high-pitched sounds, but not how we
hear low-pitched sounds, because neural signals
generated by low-pitched sounds are not so
neatly localized on the basilar membrane.

15. Frequency Theory
- Suggests an alternative explanation:
The brain reads pitch by monitoring the
frequency of neural impulses traveling up
the auditory nerve. In hearing, the theory
that the rate of nerve impulses traveling up
the auditory nerve matches the frequency
of a tone, thus enabling us to sense it
pitch.
- Can explain how we perceive low-
pitched sounds. But it, too, is problematic:
An individual neuron cannot fire faster
than 1000 times per second. Then, can we
sense sounds with frequencies above 1000
waves per second.
Place Theory
- In hearing, the theory that
links the pitch we hear with the
place where the cochlea’s
membrane is stimulated.
Place theory best explains how we
sense high pitches, frequency theory
best explains how we sense low
pitches, and some combination of
place and frequency seems to handle
the pitches in the intermediate
range.

16. Locating Sounds
How do we locate sounds?
-Sounds waves strike one ear sooner and more intensely
than the other. From this information, our nimble brain
computes the sound’s location. As you might therefore
expect, people who lose all hearing in one ear often
have difficulty locating sounds.
-Two ears better than one for at least two reasons:
sounds travels 750 miles per hour and our ears are 6
inches apart, the difference intensity and time lag are
extremely small. However , our supersensitive auditory
system can detect such minute differences (brown &
Deffenbacher, 1979 ;Middlebrooks & Green, 1991). And
to stimulate the ears experiencing with sound varying
locations, audio software can emit sounds from two
stereo speakers with varying time delays and intensity.
Hearing Loss and Deaf Culture
• What are the common causes of hearing loss, and
why does controversy surround cochlear implants?
-The ear’s intricate and delicate structure makes it
vulnerable to damage. The mechanical system that
conducts sounds waves to the cochlea cause
conduction hearing loss. If eardrums punctured or if
the tiny of the middle ear lose their ability to vibrate.
-Damage to cochlea’s hair cell receptors or their
associated nerves can causes the more common
sensorineural hearing loss (or nerve deafness) .
Occasionally, disease causes sensorineural hearing
loss, but more often the culprits are biological
changes linked with heredity, aging and prolonged
exposure to ear-splitting noise or music.

17. - The only way to restore
hearing for people with nerve
deafness is a sort of bionic ear- a
cochlear implant. This electronic
device translates sounds into
electrical signals that, wired into
the cochlea’s nerves, convey some
information about sound to the
brain.
- Cochlear implants is hotly
debated. The one side are the
hearing parents of more than 90
percent of all deaf children.
Hardware for Hearing
-An x-ray imagine shows a
cochlear implant’ array of wires
leading to 12 stimulation sites
on the auditory nerve

18. OTHER
IMPORTANT OF
SENSES
SENSE OF TOUCH
Kinesthesis
- Also called kinesthesis is sense that provides
information through receptors in the muscle,
tendons and joints enabling 9us to control and
coordinate with our bodily movements
• Sensation begin as signals generated
by touch receptors in our skin. They
travel along sensory nerves made up
of bundled fibers that connect to
neurons in the spinal cord. Then
signals move to the thalamus, which
relays information to the rest of the
brain.

19. Vestibular Sense
- Provides sense of balance and
information about body position
• Gate
- Control theory, published by
Ronald Melzack and Patrick Wall.
This theory suggests that the
spinal cord contains a neurological
“gate” is opened by the activity of
pain signals traveling up small
nerve fibers and is closed by
activity in larger fibers or by
information coming from the
brain.
SENSE OF TASTE
- Taste bud have very sensitive microscopic hairs
called microvilli. Those tiny hair send messages , so
you know if it’s sweet, sour , bitter, or salty. The
average person has about 10,000 taste buds and
they’re replaced every 2 weeks or so.

20. SENSE OF SMELL
Our ability to smell comes from specialized
sensory cells, called olfactory sensory
neurons, which are found in a small patch
of tissue high inside the nose. These cells
connect directly to the brain.
How is smell connected to memory?
Smells are handled by the olfactory bulb, the structures in the
front of the brain that sends information to the other areas of
the body’s central command for further processing. Odors take a
direct route to the limbic system, including the amygdala and
the hippocampus, the regions related to emotion and memory.
Sensory Deprivation and Restored Vision
Sensory Deprivation- the deliberate reduction or removal of stimuli
from one or more of the senses.
Restored Vision- if a person is given eyesight after knowing only
blindness, most likely that person will not be able to interpret what
he/she see. Faces, facial, expressions, color, all will be hard to
understand as that person never experienced it. But that person will
adjust to their surrounding, given time.
PERCEPTUAL ADAPTATION
Perceptual Adaptation-Is a theory that proposes the
notion that our brain and senses collaborate. Our vision
can be altered but our brain corrects this alteration.
- In vision, the ability to adjust to an artificially displaced
or even inverted visual field.
Perceptual set refers to a predisposition to perceive things
in a certain way. In other word, we often tend to notice
only certain aspects of an object or situation while
ignoring other details.

22. Perceptual Organization
How did Gestalt psychologists understand perceptual organization?
Gestalt – a German word meaning a ‘form’ or
a ‘whole’. Gestalt psychologists emphasized our
tendency to integrate pieces of information into
meaningful wholes.
e.g. Necker Cube
X
In perception the whole may exceed the sum of
its parts – Gestalt psychologists.
e.g. Table Salt
Perception is not just opening a shutter and
letting a picture print itself on the brain. We
constantly filter sensory information and infer
perceptions in ways that make sense to us. Mind
matter.

23. FORM PERCEPTION
Figure-ground - the organization of the visual
field into objects (the figures) that stand out from
their surroundings (the ground)
How do figure-ground and grouping principles contribute to our perceptions?
1. Proximity
We group nearby
figures together
2. Similarity
We group similar
figures together
3. Continuity
We perceive smooth,
continuous patterns
rather than
discontinuous ones.
4. Connectedness
We perceive each set as
a single unit because
they are uniform and
linked
5. Closure
We fill in gaps to create
a complete, whole
object
Grouping - the perceptual tendency to
organize stimuli into coherent groups
e.g.
As you read, the words are the
figure; the white paper, the ground

24. DEPTH PERCEPTION
Depth Perception - the ability to see objects in three
dimensions - although the images that strike the retina are two-
dimensional; allows us to judge distance.
e.g.
• Estimating the distance of an oncoming car or the height of a
house.
• Miniature cliff with a drop-off covered by a sturdy glass
• Visual Cliff-a laboratory device for testing depth perception in
infants and young animals. In human infants, depth perception
grows age.
How do we see the world in three dimensions?
Binocular Cues - depth cues, such as retina
disparity, that depend on the use of two eyes
e.g.
Holding two pens or pencils in front of you and touch their
tips together
Retinal Disparity - a binocular cue for perceiving depth: By
comparing images from the retinas in the two eyes, the brain
computes distance - the greater the disparity (difference) between
the two images, the closer the object l.
e.g. The floating finger sausage

25. DEPTH PERCEPTION
How do we see the world in three dimensions?
Monocular cues - depth cues, such as interposition and linear perspective, available to either eye alone
- where we depend while looking at such distances
e.g. St. Louise Gateway Arch , Light-and-shadow effect
1. Relative height
- perceiving
objects higher in
our field of vision
as farther away.
2. Relative size
- perceiving the
one that casts that
smaller retinal
image as farther
away.
3. Interposition
- perceiving an object
closer if one object
partially blocks our
view of another.
4. Linear
Perspective
-perceiving greater
distance the more
they converge.
5. Light and Shadow
- perceiving nearby
object reflects more
light to our eyes,
making the di mer
one seems farther
away.
6. Relative emotion
-perceiving that the
farther the objects
are from the fixation
point, the faster
they seem to have.

26. MOTION PERCEPTION
Phi phenomenon - an illusion of movement created when two or more adjacent lights blink on and off in quick succession.
MOTION PERCEPTION
Perceptual constancy
- perceiving objects as unchanging (having consistent shapes, size, lightness, and color) even as illumination and retinal
images change.
- an ability to recognize objects without being deceived by changes in their shape, size, brightness, or color
Shape and Size Constancies A door casts and the increasingly trapezoidal
image on our retinas as it opens, yet we still perceive it as rectangular.
Lightness Constancy (also called brightness constancy); we perceive an
object as having a constant lightness even while its illumination varies.
Color Constancy - a phenomenon where the color will remain roughly
constant as the lighting and wavelengths shift.