Ch.6 Flashcards
1
Q
define sensation
A
the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
2
Q
what is prosopagnosia?
A
face blindness (the inability to recognize faces)
3
Q
what is phonopagnosia?
A
voice blindness (the inability to recognize voices)
4
Q
define perception
A
the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events
5
Q
define Bottom-up processing
A
analysis that begins with the sensory receptors and works up to the brain’s integration of sensory information
6
Q
define Top-down processing
A
information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations
7
Q
what three things do all our sense do?
A
(1) receive sensory stimulation, often using specialized receptor cells.
(2) transform that stimulation into neural impulses.
(3) deliver the neural information to our brain.
8
Q
define transduction
A
conversion of one form of energy into another. In sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brain can interpret
9
Q
define Psychophysics
A
the study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them
10
Q
What is the rough distinction between sensation and perception?
A
Sensation is the bottom-up process by which our sensory receptors and our nervous system receive and represent stimuli. Perception is the top-down process in which our brain creates meaning by organizing and interpreting what our senses detect.
11
Q
define absolute threshold
A
the minimum stimulus energy needed to detect a particular stimulus 50 percent of the time
12
Q
who was the German scientist and philosopher who studied absolute thresholds and coined the term?
A
Gustav Fechner
13
Q
What else may detecting a weak stimuli be dependent on besides its stimuli strength?
A
our psychological states
perception is affected by our experience, expectations, alertness and motivation
14
Q
define signal detection theory
A
a theory predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise). Assumes there is no single absolute threshold and that detection depends partly on a person’s experience, expectations, motivation, and alertness
15
Q
define subliminal
A
below one’s absolute threshold for conscious awareness
16
Q
____ stimuli are stimuli that you cannot detect 50% of the time
A
subliminal
17
Q
define prime
A
the activation, often unconsciously, of certain associations, thus predisposing one’s perception, memory, or response
18
Q
An unnoticed image or word can reach your visual cortex and briefly ____ your response to a later question
A
prime
19
Q
stimulus only reaches concious awareness when…?
A
it triggers synchronized activity in multiple brain areas
20
Q
define difference threshold
A
the minimum difference between two stimuli required for detection 50 percent of the time. We experience the difference threshold as a just noticeable difference (or jnd)
21
Q
define weber’s law
A
the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount)
22
Q
define sensory adaptation
A
diminished sensitivity as a consequence of constant stimulation
23
Q
why doesn’t an object disappear from our sight if we stare at it for a long time/Why doesnt sensory adaption occur when we stare at something?
A
continual flitting from one spot to another ensures that stimulation on the eyes’ receptors continually changes
24
Q
while sensory adaptation reduces our sensitivity, it allows us….?
A
the freedom to focus on informative changes in our environment without being distracted by background chatter
25
We ____ the world not exactly as it is, but as it is useful for us to _____ it.
perceive
| perceive
26
Why is it that after wearing shoes for a while, you cease to notice them (until questions like this draw your attention back to them)?
The shoes provide constant stimulation. Sensory adaptation allows us to focus on changing stimuli.
27
define perceptual set
a mental predisposition to perceive one thing and not another
28
Imagine hearing a noise interrupted by the words “eel is on the wagon.” Likely, you would actually perceive the first word as wheel. Given “eel is on the orange,” you would more likely hear peel. what does this phenomenon suggest?
that the brain can work backward in time to allow a later stimulus to determine how we perceive an earlier one
29
Does perceptual set involve bottom-up or top-down processing? Why?
It involves top-down processing. Our perceptual set influences our interpretation of stimuli based on our experiences, assumptions, and expectations.
30
Perceptions are influenced, top-down, not only by our expectations and by the context, but also by our ____ and _____.
emotions
| motivation
31
What are sensation and perception?
Sensation is the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment. Perception is the process of organizing and interpreting this information, enabling recognition of meaningful events. Sensation and perception are actually parts of one continuous process.
32
What do we mean by bottom-up processing and top-down processing?
Bottom-up processing is sensory analysis that begins at the entry level, with information flowing from the sensory receptors to the brain. Top-down processing is information processing guided by high-level mental processes, as when we construct perceptions by filtering information through our experience and expectations.
33
what effect do stimuli below the absolute threshold have on us?
riming (the often unconscious activation of certain associations that may predispose one’s perception, memory, or response)shows that we process some information from stimuli below our absolute threshold for conscious awareness.
34
Does subliminal sensation enable subliminal persuasion?
Subliminal stimuli are those that are too weak to detect 50 percent of the time. While subliminal sensation is a fact, such sensations are too fleeting to enable exploitation with subliminal messages: There is no powerful, enduring effect.
35
What is the function of sensory adaptation?
Sensory adaptation (our diminished sensitivity to constant or routine odors, sounds, and touches) focuses our attention on informative changes in our environment.
36
How do our expectations, contexts, motivation, and emotions influence our perceptions?
Perceptual set is a mental predisposition that functions as a lens through which we perceive the world. Our learned concepts (schemas) prime us to organize and interpret ambiguous stimuli in certain ways. Our physical and emotional context, as well as our motivation, can create expectations and color our interpretation of events and behaviors.
37
define wavelength
the distance from the peak of one light or sound wave to the peak of the next. Electromagnetic wavelengths vary from the short blips of cosmic rays to the long pulses of radio transmission
38
define hue
the dimension of color that is determined by the wavelength of light; what we know as the color names blue, green, and so forth
39
define intensity
the amount of energy in a light wave or sound wave, which influences what we perceive as brightness or loudness. Intensity is determined by the wave’s amplitude (height)
40
define pupil
he adjustable opening in the center of the eye through which light enters
41
define 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
42
when you feel disgust or are about to answer no to a question what do your pupils do?
constrict
43
when you are feeling amorous what do your pupils do? what does this signal?
your pupils dilate and your dark eyes subtly signal your interest
44
define lens
the transparent structure behind the pupil that changes shape to help focus images on the retina
45
define retina
the light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information
46
define accommodation
1) in developmental psychology, adapting our current understandings (schemas) to incorporate new information. (2) in sensation and perception, the process by which the eye’s lens changes shape to focus near or far objects on the retina
47
define rods
retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don’t respond
48
define cones
retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. The cones detect fine detail and give rise to color sensations
49
what are the names of the two buried receptor cells that cover the back of the eye?
rods and cones
50
define optic nerve
the nerve that carries neural impulses from the eye to the brain
51
what is the optic nerve made up of?
ganglion cells intertwined axons
52
approximately how many ganglion nerves is the optic nerve made up of?
1 million
53
approximately how many nerves is the auditory nerve made up of?
30,000 nerves
54
how many messages can the optic nerve send at once?
about 1 million
55
define blind spot
the point at which the optic nerve leaves the eye, creating a “blind” spot because no receptor cells are located there
56
define fovea
the central focal point in the retina, around which the eye’s cones cluster
57
light energy triggers a chemical change which sparks neural signals which activate the _______ cells
bipolar cells
58
___ cells activate the ganglion cells which sends visual sensory information to the brain
bipolar
59
do cones have their own bipolar cells dedicated to each cone? what effect does this have?
yes. The direct connections preserve the cones’ precise information, making them better able to detect fine detail.
60
do rods have their own bipolar cells dedicated to each rod? what effect does this have?
no. this causes visual infromation from rods to be less distinct and blurry
61
how long does it take for your eyes to adjust to darkness? What does this coincide with and may be the reasoning for?
about 20 minutes which is the average twilight transition time between the sun setting and darkness
62
Some nocturnal animals, such as toads, mice, rats, and bats, have impressive night vision thanks to having many more ____ (rods/cones) than ______(rods/cones) in their retinas. These creatures probably have very poor ______(color/black-and-white) vision.
rods
cones
colour
63
Cats are able to open their ______________ much wider than we can, which allows more light into their eyes so they can see better at night.
pupils
64
define Young-Helmholtz trichromatic (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 in combination, can produce the perception of any color
65
"colour blind" people are not actually colour blind but have _______
colour-deficient vision
66
what causes people to be colour blind?
They simply lack functioning red-or green-sensitive cones, or sometimes both
67
define 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 red; others are stimulated by red and inhibited by green
68
What are two key theories of color vision? Are they contradictory or complementary?
The Young-Helmholtz trichromatic theory shows that the retina contains color receptors for red, green, and blue. The opponent-process theory shows that we have opponent-process cells in the retina for red-green, yellow-blue, and white-black. These theories are complementary and outline the two stages of color vision: (1) The retina’s receptors for red, green, and blue respond to different color stimuli. (2) The receptors’ signals are then processed by the opponent-process cells on their way to the visual cortex in the brain.
69
define feature detectors
nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement
70
what happens when researchers can temporarily disrupt the brain’s face-processing areas with magnetic pulses?
people cannot recognize faces, but they can recognize houses, because the brain’s face-perception occurs separately from its object-perception
71
define parallel processsing
the processing of many aspects of a problem simultaneously; the brain’s natural mode of information processing for many functions
72
What is the rapid sequence of events that occurs when you see and recognize a friend?
Light waves reflect off the person and travel into your eye, where the receptor cells in your retina convert the light waves’ energy into neural impulses sent to your brain. Your brain processes the subdimensions of this visual input–including depth, movement, form, and color–separately but simultaneously. It interprets this information based on previously stored information and your expectations into a conscious perception of your friend.
73
define gestalt
an organized whole. Gestalt psychologists emphasized our tendency to integrate pieces of information into meaningful wholes
74
define figure ground
the organization of the visual field into objects (the figures) that stand out from their surroundings (the ground)
75
define grouping
the perceptual tendency to organize stimuli into coherent groups
76
In terms of perception, a band’s lead singer would be considered ___________ (figure/ground), and the other musicians would be considered ___________ (figure/ground).
figure
| ground
77
What do we mean when we say that, in perception, the whole may exceed the sum of its parts?
Gestalt psychologists used this saying to describe our perceptual tendency to organize clusters of sensations into meaningful forms or coherent groups.
78
define 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
79
define visual cliff
a laboratory device for testing depth perception in infants and young animals
80
define binocular cues
depth cues, such as retinal disparity, that depend on the use of two eyes
81
define 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
82
what allows humans to perceive depth
having two eyes that are approx 2.5 inches a apart. images seen with greater retinal disparity are closer together
83
How do we normally perceive depth?
We are normally able to perceive depth thanks to (1) binocular cues (which are based on our retinal disparity), and (2) monocular cues (which include relative height, relative size, interposition, linear perspective, light and shadow, and relative motion).
84
define monocular cues
depth cues, such as interposition and linear perspective, available to either eye alone
85
what issues do brains have with perceiving motion
large and small objects move at the same speed, the large objects appear to move more slowly
86
why are children more at risks for pedestrian accidents in terms of motion perception
Normally your brain computes motion based partly on its assumption that shrinking objects are retreating (not getting smaller) and enlarging objects are approaching. In young children, this ability to correctly perceive approaching (and enlarging) vehicles is not yet fully developed, which puts them at risk for pedestrian accidents
87
Our brain also perceives a rapid series of slightly varying images as continuous _____
movement
88
define phi phenomenon
an illusion of movement created when two or more adjacent lights blink on and off in quick succession
89
define perceptual constancy
perceiving objects as unchanging (having consistent color, brightness, shape, and size) even as illumination and retinal images change
90
define colour constancy
perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths reflected by the objects
91
could someone who was blind that can now see recognize shapes visually that the knew by touch?
no
92
for normal sensory and perceptual development, there is a ______
critical period
93
define perceptual adaptation
in vision, the ability to adjust to an artificially displaced or even inverted visual field
94
Where are feature detectors located, and what do they do?
Feature detectors, located in the visual cortex, respond to specific features of the visual stimulus, such as shape, angle, or movement. Supercell clusters in other critical areas respond to more complex patterns.
95
How does the brain use parallel processing to construct visual perceptions?
Through parallel processing, the brain handles many aspects of vision (color, movement, form, and depth) simultaneously. Other neural teams integrate the results, comparing them with stored information and enabling perceptions.
96
How did the Gestalt psychologists understand perceptual organization, and how do figure-ground and grouping principles contribute to our perceptions?
Gestalt psychologists searched for rules by which the brain organizes fragments of sensory data into gestalts (from the German word for “whole”), or meaningful forms. In pointing out that the whole may exceed the sum of its parts, they noted that we filter sensory information and construct our perceptions.
To recognize an object, we must first perceive it (see it as a figure) as distinct from its surroundings (the ground). We bring order and form to stimuli by organizing them into meaningful groups, following such rules as proximity, continuity, and closure.
97
How do we use binocular and monocular cues to perceive the world in three dimensions?
Depth perception is our ability to see objects in three dimensions and judge distance. The visual cliff and other research demonstrate that many species perceive the world in three dimensions at, or very soon after, birth. Binocular cues, such as retinal disparity, are depth cues that rely on information from both eyes. Monocular cues (such as relative size, interposition, relative height, relative motion, linear perspective, and light and shadow) let us judge depth using information transmitted by only one eye.
98
how do we perceive motion?
As objects move, we assume that shrinking objects are retreating and enlarging objects are approaching. A quick succession of images on the retina can create an illusion of movement, as in stroboscopic movement or the phi phenomenon.
99
How do perceptual constancies help us construct meaningful perceptions?
Perceptual constancy enables us to perceive objects as stable despite the changing image they cast on our retinas.
100
what is the moon illusion?
The Moon looks up to 50 percent larger when near the horizon than when high in the sky because monocular cues to objects’ distances make the horizon Moon seem farther away. If it’s farther away, our brain assumes, it must be larger than the Moon high in the night sky
101
What does research on restored reveal about the effects of experience on perception?
Experience guides our perceptual interpretations. People blind from birth who gained sight after surgery lack the experience to visually recognize shapes, forms, and complete faces.
102
What does research on sensory restriction reveal about the effects of experience on perception?
Sensory restriction research indicates that there is a critical period for some aspects of sensory and perceptual development. Without early stimulation, the brain’s neural organization does not develop normally.
103
What does research on perceptual adaptation reveal about the effects of experience on perception?
People given glasses that shift the world slightly to the left or right, or even upside down, experience perceptual adaptation. They are initially disoriented, but they manage to adapt to their new context.
104
define audition
the sense or act of hearing
105
define frequency
the number of complete wavelengths that pass a point in a given time
106
the ____ of sound waves determines their loudness
amplitude
107
the ____ of the sounds wavelengths determines the ___ of the sound
pitch
108
define pitch
a tone’s experienced highness or lowness; depends on frequency
109
how does the measure of sound in decibels represent the intensity of the sound
Every 10 decibels correspond to a tenfold increase in sound intensity with 0 decibels representing the absolute threshold for hearing
110
define middle ear
the chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochlea’s oval window
111
define cochlea
a coiled, bony, fluid-filled tube in the inner ear; sound waves traveling through the cochlear fluid trigger nerve impulses
112
define inner ear
the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs
113
how many people in the world are affected by hearing loss?
360 million
114
define sensorineural hearing loss
the most common form of hearing loss, also called nerve deafness; caused by damage to the cochlea’s receptor cells or to the auditory nerves
115
define conduction hearing loss
less common form of hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea
116
how many teens have hearing loss?
1 in 5
117
define cochlear implant
a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea
118
What are the basic steps in transforming sound waves into perceived sound?
The outer ear collects sound waves, which are translated into mechanical waves by the middle ear and turned into fluid waves in the inner ear. The auditory nerve then translates the energy into electrical waves and sends them to the brain, which perceives and interprets the sound.
119
The amplitude of a sound wave determines our perception of __________ (loudness/pitch)
loudness
120
The longer the sound waves are, the ______________ (lower/higher) their frequency is and the ______________ (higher/lower) their pitch.
lower
| lower
121
how does your brain interpret loudness?
your brain interprets loudness from the number of activated hair cells.
122
define place theory
in hearing, the theory that links the pitch we hear with the place where the cochlea’s membrane is stimulated
123
define frequency theory
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 its pitch. (Also called temporal theory.)
124
give three reasons why a combination of the place theory and the frequency theory would work best
(1) Place theory best explains how we sense high pitches.
(2) Frequency theory best explains how we sense low pitches.
(3) Some combination of place and frequency theories seems to handle the pitches in the intermediate range.
125
what are the two theories on how we discriminate pitch
place theory and frequency theory
126
why is the placement of one ear on each side of the head ideal?
it allows for stereophonic hearing (3D hearing)
127
In experiments, were strangers separated by a curtain, using their hands to touch only each other’s forearms, able to communicate anger, fear, disgust, love, gratitude, and sympathy?
yes, at much higher levels then chance
128
what 4 basic and distinct skin senses is our "sense of touch" made up of?
warmth, cold, pain, pressure
129
define nociceptors
sensory receptors that enable the perception of pain in response to potentially harmful stimuli.
130
define gate control theory
the theory that the spinal cord contains a neurological “gate” that blocks pain signals or allows them to pass on to the brain. The “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
131
who came up with the gate control theory?
Wall and Melzack
132
how many people experience phantom limb pain?
7 in 10 of those who lost limbs
133
will people recall experiencing less pain if they have a short but painful right until the last second experience or a prolongued experience with more pain the slowly tapers of at the end experience?
people recall feeling less pain if they go the root in which pain slowly subsides vs abruptly ending
134
can pain be socially created?
yes, when others are in pain your brain may mirror the brain activity of the person in pain causing you to feel pain. we are also more likely to experience pain in the presence of other
135
what psychological things influence our feeling of pain?
our attention to pain and our expectations of pain
136
when holding two pipes one which has warm water streaming through it and one which has cold water streaming through it what will we perceive the temperature of the water to be?
hot
137
is it a possible for a person who is really into perhaps a soccer game to not realize they have broken a leg?
yes
138
what is the up side of people with mutated genes that allow them to feel less or no pain?
it is helping with research to be able to block out pain in others
139
what two things can naturally lead to diminished pain?
the release of endorphins and distraction from the pain
140
define hypnosis
a social interaction in which one person (the hypnotist) suggests to another (the subject) that certain perceptions, feelings, thoughts, or behaviors will spontaneously occur
141
what percentage of the population can be so hypnotized that they undergo major surgery without anesthesia?
about 10%
142
how many people (%) can get pain relief hypnotism?
about 50%
143
define dissociation
a split in consciousness, which allows some thoughts and behaviors to occur simultaneously with others
144
define posthypnotic suggestion
a suggestion, made during a hypnosis session, to be carried out after the subject is no longer hypnotized; used by some clinicians to help control undesired symptoms and behaviors
145
what are they two theories on how hypnosis works?
(1) hypnosis is a form of normal social influence
| (2) hypnosis as a special dual-processing state of dissociation—a split between different levels of consciousness
146
what does the dissociation theory of hypnosis explain?
(1) why people hypnotized for pain relief may show brain activity in areas that receive sensory information, but not in areas that normally process pain-related information
(2) xplains why, when no one is watching, hypnotized people may carry out posthypnotic suggestions
147
name the 5 tastes
sweet, salty, sour, bitter and umami
148
about how many taste buds does a person have?
200 or more
149
how many taste receptors are there in a taste bud pore?
50-100
150
how do taste receptor cells taste food?
they project antenna-like hairs that sense food molecules
151
as you age your number of taste buds ____. what things can accelerate this?
decreases. smoking and drinking alcohol can increase this decline
152
is our sense of taste affected by our expectations?
yes. people like sausage that was labeled meat over the same sausage labelled vege. people also prefered wine that was labeled more expensive even if it was indentical to the cheap stuff
153
how many receptor cells are in the nose?
20 million
154
do men or women have a better sense of smell?
woman, especially young women
155
do past associations affect your perception of a smell?
yes
156
How does our system for sensing smell differ from our sensory systems for touch and taste?
We have four basic touch senses and five basic taste sensations. But we have no basic smell receptors. Instead, different combinations of odor receptors send messages to the brain, enabling us to recognize some 10,000 different smells.
157
define kinesthisia
the system for sensing the position and movement of individual body parts
158
define vestibular sense
the sense of body movement and position, including the sense of balance
159
what allows us to sense what direction our head is tilted?
vestibular sacs in our inner ear
160
Where are the kinesthetic receptors and the vestibular sense receptors located?
Kinesthetic receptors are located in our joints, tendons, and muscles. Vestibular sense receptors are located in our inner ear.
161
Smell + texture + taste=?
flavour
162
define sensory interaction
the principle that one sense may influence another, as when the smell of food influences its taste
163
Seeing the mouth movements for ga while hearing ba we may perceive da. what is this phenomenon called?
McGurk effect
164
define embodied cognition
in psychological science, the influence of bodily sensations, gestures, and other states on cognitive preferences and judgments
165
define Extrasensory perception (ESP)
the controversial claim that perception can occur apart from sensory input; includes telepathy, clairvoyance, and precognition
166
define parapsychology
the study of paranormal phenomena, including ESP and psychokinesis
167
What are the characteristics of air pressure waves that we hear as sound?
Sound waves are bands of compressed and expanded air. Our ears detect these changes in air pressure and transform them into neural impulses, which the brain decodes as sound. Sound waves vary in amplitude, which we perceive as differing loudness, and in frequency, which we experience as differing pitch.
168
How does the ear transform sound energy into neural messages?
Through a mechanical chain of events, sound waves traveling through the auditory canal cause tiny vibrations in the eardrum. The bones of the middle ear amplify the vibrations and relay them to the fluid-filled cochlea. Rippling of the basilar membrane, caused by pressure changes in the cochlear fluid, causes movement of the tiny hair cells, triggering neural messages to be sent (via the thalamus) to the auditory cortex in the brain.
169
what is the layout of the ear
The outer ear is the visible portion of the ear. The middle ear is the chamber between the eardrum and cochlea. The inner ear consists of the cochlea, semicircular canals, and vestibular sacs.
170
how does sensorineural hearing loss (or nerve deafness) occurs
it occurs from damage to the cochlea’s hair cells or their associated nerves.
171
how does conduction hearing loss occur
it occurs from damage to the mechanical system that transmits sound waves to the cochlea. Cochlear implants can restore hearing for some people.
172
How do we detect loudness?
Loudness is not related to the intensity of a hair cell’s response. The brain interprets loudness from the number of activated hair cells.
173
How do we discriminate pitch?
Place theory explains how we hear high-pitched sounds, and frequency theory explains how we hear low-pitched sounds. (A combination of the two theories explains how we hear pitches in the middle range.) Place theory proposes that our brain interprets a particular pitch by decoding the place where a sound wave stimulates the cochlea’s basilar membrane. Frequency theory proposes that the brain deciphers the frequency of the neural impulses traveling up the auditory nerve to the brain.
174
How do we locate sounds?
Sound waves strike one ear sooner and more intensely than the other. To locate sounds, the brain analyzes the minute differences in the sounds received by the two ears and computes the sound’s source.
175
How do we sense touch?
Our sense of touch is actually several senses—pressure, warmth, cold, and pain—that combine to produce other sensations, such as “hot.”
176
What biological, psychological, and social-cultural influences affect our experience of pain?
Pain reflects bottom-up sensations (such as input from nociceptors, the sensory receptors that detect hurtful temperatures, pressure, or chemicals) and top-down processes (such as experience, attention, and culture). One theory of pain is that a “gate” in the spinal cord either opens to permit pain signals traveling up small nerve fibers to reach the brain, or closes to prevent their passage. The biopsychosocial perspective views our perception of pain as the sum of biological, psychological, and social-cultural influences. For example, our experience of pain is influenced by activity in the spinal cord’s large and small fibers (a biological influence), attention to pain (a psychological influence), and cultural expectations (a social-cultural influence).
177
How do placebos help control pain?
Placebos can help by dampening the central nervous system’s attention and response to painful experiences.
178
How does distraction help control pain?
draw people’s attention away from painful stimulation.
179
How does hypnosis help control pain?
Hypnosis, which increases our response to suggestions, can also help relieve pain. Posthypnotic suggestion is used by some clinicians to control undesired symptoms.
180
In what ways are our senses of taste and smell similar, and how do they differ?
Taste and smell are both chemical senses. Taste is a composite of five basic sensations and of the aromas that interact with information from the taste receptor cells of the taste buds.
There are no basic sensations for smell. We smell something when molecules of a substance carried in the air reach a tiny cluster of 20 million receptor cells at the top of each nasal cavity. Odor molecules trigger combinations of receptors, in patterns that the olfactory cortex interprets. The receptor cells send messages to the brain’s olfactory bulb, then to the temporal lobe, and to parts of the limbic system.
181
How do we sense our body’s position and movement?
Through kinesthesia, we sense the position and movement of our body parts. We monitor our head’s (and thus our body’s) position and movement, and maintain our balance, with our vestibular sense.
182
How does sensory interaction influence our perceptions?
Our senses can influence one another. This sensory interaction occurs, for example, when the smell of a favorite food amplifies its taste
183
what is embodied cognition?
Embodied cognition is the influence of bodily sensations, gestures, and other states on cognitive preferences and judgments.
