Chapter 7 - Hearing, Touch, Smell, Taste and Attention

Question 1

Exteroceptive sensory systems, p. 190

Answer 1

the auditory (hearing), somatosensory (touch), olfactory (smell),
and gustatory (taste) systems

Question 2

Primary sensory cortex, p. 191

Answer 2

the area of sensory cortex that receives most of
its input directly from the thalamic relay nuclei of that system.

For example, as you learned in Chapter 6, the primary
visual cortex is the area of the cerebral cortex that receives most of its input from the lateral geniculate nucleus of the thalamus

Question 3

Secondary sensory cortex, p. 191

Answer 3

The secondary sensory cortex of a system
comprises the areas of the sensory cortex that receive most of their input from the primary sensory cortex of that system or from other areas of secondary sensory cortex of the same system.

Question 4

Association cortex, p. 191

Answer 4

Association cortex is any area of cortex that
receives input from more than one sensory system.

Most input to areas of association cortex comes via areas of secondary sensory cortex

Question 5

Hierarchical organization, p. 191

Answer 5

sensory structures are organized in a hierarchy on the basis of the specificity and complexity of their function. As one moves through a sensory system from receptors, to thalamic nuclei, to primary sensory cortex, to secondary sensory cortex, to association cortex, one finds neurons that respond optimally to stimuli of greater and greater specificity and complexity.

Each level of a sensory hierarchy receives most
of its input from lower levels and adds another layer of
analysis before passing it on up the hierarchy

Question 6

Sensation, p. 192

Answer 6

the process of detecting the presence of stimuli

Question 7

Perception, p. 192

Answer 7

higher-order process of integrating, recognizing, and interpreting complete patterns of sensations

Question 8

Functional segregation, p. 192

Answer 8

However, research has shown that functional segregation, rather than functional homogeneity, characterizes the organization of sensory systems. It is now clear that each of the three levels of cerebral cortex—primary, secondary, and
association—in each sensory system contains functionally distinct areas that specialize in different kinds of analysis

Question 9

Parallel processing, p. 192

Answer 9

the simultaneous analysis of a signal in different ways by the multiple parallel pathways of a neural network.

Question 10

Fourier analysis, p. 194

Answer 10

mathematical procedure for breaking down complex waves into their component sine waves

Question 11

Tympanic membrane, p. 194

Answer 11

the eardrum

Sound waves travel
from the outer ear down the auditory canal and cause
the tympanic membrane (the eardrum) to vibrate. These vibrations are then transferred to the three ossicles

Question 12

Ossicles, p. 194

Answer 12

the
small bones of the middle ear: the malleus (the hammer), the incus (the anvil), and the stapes (the stirrup).

The vibrations of the stapes trigger vibrations of the membrane called the oval window

Question 13

Oval window, p. 194

Answer 13

transfers the vibrations to the fluid of the snail-shaped cochlea

converts sound waves to water-borne waves

Question 14

Cochlea, p. 194

Answer 14

cochlea (kokhlos
means “land snail”). The cochlea is a long, coiled tube
with an internal structure running almost
to its tip.

Question 15

Organ of Corti, p. 194

Answer 15

an internal structure running almost to the tip of the cochlea

Each pressure change at the oval window travels along the organ of Corti as a wave.

Question 16

Hair cells, p. 194

Answer 16

auditory receptors

Question 17

Basilar membrane, p. 194

Answer 17

where hair cells are mounted

Question 18

Tectorial membrane, p. 194

Answer 18

rests on hair cells

Question 19

Auditory nerve, p. 194

Answer 19

a branch of cranial nerve VIII (the

auditory-vestibular nerve).

Question 20

Retinotopic, p. 195

Answer 20

organization of the visual system

Question 21

Tonotopic, p. 195

Answer 21

organization of the auditory system, arrayed according to frequency

Question 22

Semicircular canals, p. 196

Answer 22

the receptive organs of the vestibular system

Question 23

Vestibular system, p. 196

Answer 23

carries information about the direction and intensity of head movements, which helps us keep our balance

Question 24

Superior olives, p. 196

Answer 24

signals from both ears are combined

receives projections from the cochlear nuclei, project via the lateral lemniscus to the inferior colliculi

Question 25

Inferior colliculi, p. 196

Answer 25

main auditory center
signal integration
pitch discrimination
synapse on neurons
that project to the medial geniculate nuclei of the thalamus

Question 26

Medial geniculate nuclei, p. 196

Answer 26

part of the thalamus

involved in auditory processing, directing one’s attention toward specific auditory stimuli

Question 27

Tinnitus, p. 199

Answer 27

ringing of the ears

Question 28

Free nerve endings, p. 201

Answer 28

neuron endings with no specialized structures on them

Question 29

Pacinian corpuscles, p. 201

Answer 29

Nerves that detect deep pressure

The largest and deepest
cutaneous receptors are the onionlike Pacinian corpuscles;
because they adapt rapidly, they respond to sudden displacements of the skin but not to constant pressure.

Question 30

Merkel’s disks, p. 201

Answer 30

Merkel’s disk are slow-adapting, unencapsulated nerve endings that respond to light touch; they are present in the upper layers of skin that has hair or is glabrous

Question 31

Ruffini endings, p. 201

Answer 31

Ruffini endings are slow adapting, encapsulated receptors that respond to skin stretch and are present in both the glabrous and hairy skin

Question 32

Stereognosis, p. 201

Answer 32

The identification of objects by touch

Question 33

Dermatome, p. 201

Answer 33

The area of the body that is innervated by the left and right dorsal roots of a given segment of the spinal cord

Question 34

Dorsal-column medial-lemniscus

system, p. 201

Answer 34

tends to carry

information about touch and proprioception

Question 35

Anterolateral system, p. 201

Answer 35

tends to carry information about

pain and temperature

Question 36

Dorsal columns, p. 202

Answer 36

a part of the spinal cord which is responsible for transporting sensory input from the body to the cerebral cortex

Question 37

Medial lemniscus, p. 202

Answer 37

a channel for sensory data to the thalamus from the gracile and cuneate nuclei in the brain

Nearly all the cutaneous mechanoreceptors in the body that transmit information about light touch, vibration, and pressure signals will travel through the dorsal-column medial lemniscus pathway.

Question 38

Ventral posterior nucleus, p. 202

Answer 38

The ventral posterior nuclei also receive
input via the three branches of the trigeminal nerve, which carry somatosensory information from the contralateral areas of the face.

Most neurons of the ventral
posterior nucleus project to the primary
somatosensory cortex (SI); others project to
the secondary somatosensory cortex (SII) or
the posterior parietal cortex.

Question 39

Somatotopic, p. 203

Answer 39

organized according to a map of the body

surface

Question 40

Somatosensory homunculus, p. 203

Answer 40

the somatosensory homunculus is distorted;
the greatest proportion of SI is dedicated
to receiving input from the parts of the
body we use to make tactile discriminations (e.g., hands, lips, and tongue).

Question 41

Astereognosia, p. 205

Answer 41

the inability to recognize objects by touch.

Question 42

Asomatognosia, p. 205

Answer 42

the failure to recognize parts of one’s

own body

Question 43

Anosognosia, p. 205

Answer 43

the failure of neuropsychological

patients to recognize their own symptoms

Question 44

Contralateral neglect, p. 205

Answer 44

the tendency not to respond to stimuli

that are contralateral to a right-hemisphere injury

Question 45

Rubber-hand illusion, p. 206

Answer 45

the feeling that an extraneous object, in this case a

rubber hand, is actually part of one’s own body

Question 46

Anterior cingulate cortex, p. 207

Answer 46

The cortical area that has been most frequently linked
to pain

However, the anterior cingulate cortex appears to be involved in the expectation of pain, the emotional reaction
to pain, and adaptive responses to minimize pain—rather
than to the perception of pain itself

Question 47

Periaqueductal gray (PAG), p. 207

Answer 47

has analgesic (pain-blocking) effects

Question 48

Endorphins, p. 207

Answer 48

they actually lower the feeling of pain in the body and can create a feeling of bliss or euphoria

Question 49

Neuropathic pain, p. 208

Answer 49

severe chronic pain in the absence of a recognizable pain stimulus

Question 50

Flavor, p. 209

Answer 50

Molecules of food excite both smell and taste receptors and produce an integrated sensory impression termed flavor.

Question 51

Pheromones, p. 209

Answer 51

chemicals that influence the physiology and behavior of conspecifics (members
of the same species)

Question 52

Olfactory mucosa, p. 209

Answer 52

The olfactory receptor cells are located in the upper part of the nose, embedded in a layer of mucus-covered tissue called the olfactory mucosa

Question 53

Olfactory bulbs, p. 209

Answer 53

receives signal from olfactory mucosa through cribriform plate

involved in smell perception

Question 54

Olfactory glomeruli, p. 209

Answer 54

The axons of olfactory receptors terminate in discrete

clusters of neurons that lie near the surface of the olfactory bulbs

Question 55

Chemotopic, p. 210

Answer 55

map of the olfactory system, glomeruli sensitive to particular odors will be located at the same sites on both sides

Question 56

Piriform cortex, p. 210

Answer 56

no, 2011).
Each olfactory bulb projects
axons to several structures of
the medial temporal lobes, including the amygdala
and the piriform cortex—an area of medial temporal
cortex adjacent to the amygdala (see Bekkers & Suzuki,
2013). The piriform cortex is considered to be primary
olfactory cortex, but this designation is somewhat arbitrary

Question 57

Medial dorsal nuclei, p. 210

Answer 57

One projects diffusely to the limbic
system, and the other projects via the medial dorsal
nuclei of the thalamus to the orbitofrontal cortex

Question 58

Orbitofrontal cortex, p. 210

Answer 58

the
area of cortex on the inferior surface of the frontal lobes
next to the orbits (eye sockets)

Question 59

Taste buds, p. 211

Answer 59

taste receptor cells are found on the tongue

and in parts of the oral cavity; they typically occur in clusters of 50 to 100

Question 60

Anosmia, p. 213

Answer 60

inability to smell

Question 61

Ageusia, p. 213

Answer 61

inability to taste

Question 62

Selective attention, p. 213

Answer 62

It improves the
perception of the stimuli that are its focus, and it interferes
with the perception of the stimuli that are not its focus

Question 63

Top-down, p. 214

Answer 63

(from higher to lower

levels) neural mechanisms

Question 64

Bottom-up, p. 214

Answer 64

from lower to higher

levels) neural mechanisms

Question 65

Cocktail-party phenomenon, p. 214

Answer 65

the fact that even when
you are focusing so intently on one conversation that you are totally unaware of the content of other conversations going on around you, the mention of your name in one of the other conversations will immediately gain access to
your consciousness.

This phenomenon suggests that your brain can block from conscious awareness all stimuli except
those of a particular kind while still unconsciously monitoring the blocked-out stimuli just in case something comes up
that requires your attention.

Question 66

Change blindness, p. 214

Answer 66

It occurs because,
contrary to our impression, when we view a scene, we
have absolutely no memory for parts of the scene that are not the focus of our attention. When viewing the scene in
Figure 7.21, most volunteers attend to the two people and do not notice when the picture disappears from the wall between them. Because they have no memory of the parts of the image to which they did not attend, they are not aware when those parts change.

Question 67

Simultanagnosia, p. 216

Answer 67

a difficulty in attending
visually to more than one object at a time.
Because the dorsal stream of the posterior
parietal cortex is responsible for visually localizing objects
in space, you may have hypothesized that the patient’s
problem was associated with damage to this area. If you did,
you were correct. Simultanagnosia is usually associated with
bilateral damage to the posterior parietal cortex.