Transcript PSYCHOLOGY (8th Edition) David Myers

EXPLORING
PSYCHOLOGY
EIGHTH EDITION IN MODULES
David Myers
PowerPoint Slides
Aneeq Ahmad
Henderson State University
Worth Publishers, © 2011
Sensation and Perception
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The Other Senses
Module 15
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Hearing
 The Stimulus Input: Sound Waves
 The Ear
 Perceiving Loudness
 Locating Sounds
Kinesthesis and Vestibular Sense
Touch
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Pain
 Understanding Pain
 Controlling Pain
Taste
 Sensory Interaction
Smell
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Hearing
The Stimulus Input: Sound Waves
Audition is the act of hearing and sound waves,
compressing and expanding air molecules, are the
stimulus our ears detect then transform into into
nerve impulses that our brains decode as sound.
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The Physical Properties of Waves
The strength, or amplitude, of sound waves determines
loudness. The frequency, or number of complete waves
lengths to pass a point in a given time, determines pitch, a
sounds perceived highness or lowness.
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The Ear
To convert sound waves into neural activity
the outer ear first collects and sends sounds to
the eardrum. The middle ear, transmits the
vibrations via three tiny bones (hammer,
anvil, stirrup) to the cochlea, a snail-shaped
tube in the inner ear, causing it’s membrane
to vibrate.
This causes ripples in the basilar membrane,
bending the hair cells lining its surface,
triggering impulses in the nerve cells, whose
axons form the auditory nerve, which sends
neural messages to the auditory cortex.
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The Ear
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The Ear
Damage to hair cells
accounts for most
hearing loss. Sounds
that exceed 100 decibels,
especially if prolonged
or repeated are
potentially harmful.
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Locating Sounds
Because we have two ears, sounds that reach
one ear faster than the other ear cause us to
localize the sound.
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Kinesthesis and Vestibular Sense
The vestibular sense monitors the head (and
body’s) position. The semicircular canals and
vestibular sacs in the inner ear contain fluid which
moves when the head moves triggering hairlike
receptors which send messages to the cerebellum
enabling you to sense your position and maintain
balance.
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Kinesthesis and Vestibular Sense
The sense of our body parts’ position and
movement is called kinesthesis and is
enabled by sensors in the joints, tendons,
bones, ears, and skin.
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Touch
The sense of touch is a mix of distinct skin
senses—pressure, warmth, cold, and pain. Only
pressure has identifiable receptors. Other skin
sensations are variations of the basic four.
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Touch
Touch sensations involve more than tactile stimulation
as illustrated by the rubber-hand illusion.
When a researcher simultaneously touches a volunteer’s real and fake
hands, the volunteer feels as though the seen fake hand is her own. 15
Pain
Pain tells the body that something has gone
wrong. Usually pain results from damage to the
skin and other tissues. A rare disease exists in
which the afflicted person feels no pain.
AP Photo/ Stephen Morton
Ashley Blocker (right) feels neither pain
nor extreme hot or cold.
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Biological Influences
No one type of
stimulus triggers
pain. Instead, there
are different
nociceptors—
sensory receptors
that detect hurtful
temperatures,
pressure, or
chemicals.
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Gate-Control Theory
Melzack and Wall (1965, 1983) proposed that our
spinal cord contains neurological “gates” that
either block pain or allow it to be sensed.
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Biopsychosocial Influences
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Controlling Pain
Pain can be controlled by a number of therapies
including, drugs, surgery, acupuncture, exercise,
hypnosis, and even thought distraction.
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Taste
Traditionally, taste sensations consisted of sweet, salty,
sour, and bitter tastes. Recently, receptors for a fifth
taste have been discovered called “Umami”.
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Taste
Taste is a chemical sense. Each taste bud on the
tongue contains a pore that catches food
chemicals. In each pore, 50-100 taste receptor
cells project antenna-like hairs that sense food
molecules. Some receptors respond mainly to
sweet-tasting molecules, others to salty, and so
on.
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Sensory Interaction
When one sense affects another sense, sensory
interaction takes place. So, the taste of strawberry
interacts with its smell and its texture on the
tongue to produce flavor.
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Smell
Like taste, smell is a chemical sense. Odorants
enter the nasal cavity to stimulate 5 million
receptors to sense smell. Unlike taste, there are
many different forms of smell.
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Smell and Memories
The brain region for
smell (in red) is closely
connected with the
brain regions involved
with memory (limbic
system). That is why
strong memories are
made through the sense
of smell.
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