chapter 6 notes

Question 1

amplitude

Answer 1

intensity measured in decibels and perceived as loudness

Question 2

frequency

Answer 2

measured in number of cycles per second, or hertz, and perceived as pitch
-a physical property of a sound

Question 3

timbre

Answer 3

characteristic sound quality of an instrument, determined by the intensities of its harmonics

Question 4

transduced

Answer 4

conversion of one energy to an action potential that inform the brain

Question 5

pinna

Answer 5

collect sound waves
external part of an ear

Question 6

ear cannal

Answer 6

tube leading from the pinna to the tympanic membrane

Question 7

ossicles

Answer 7

three small bones that transmit vibration across the middle ear, from tympanic membrane to oval window

Question 8

tympanic membrane

Answer 8

(eardrum) taut membrane, at the inner end of the ear canal that captures sound vibrations in air

Question 9

oval window

Answer 9

location of the cochlea at which vibrations are transmitted from ossicles to interior of the cochlea

Question 10

cochlea

Answer 10

where transduction happens

Question 11

organ of corti

Answer 11

is the part of the cochlea that converts sound into neural activity
main structures
1. sensory cells, or hair cells
2. framework of supporting cells
3. terminations of the auditory nerve fibers

Question 12

basilar membrane

Answer 12

-at the base of the organ of corti
-auditory transduction

Question 13

stereocilia

Answer 13

tiny hairs, protrude from each hair cell
-tiny
fibers that open ion channels when the stereocilia bend
-A depolarization of the hair cell occurs and
neurotransmitter is released

Question 14

inner hair cells

Answer 14

a single row near the central axis
IHC afferents convey action potentials that provide
sound perception to the brain.
* IHC efferent lead from the brain to the IHCs, allowing
the brain to control responsiveness of IHCs.

Question 15

outer hair cells

Answer 15

three rows
OHC afferents convey information to the brain about the
mechanical state of the basilar membrane, not sounds
themselves.
* OHC efferents lead from the brain to OHCs, allowing the
brain to modify the stiffness of the basilar membrane,
thus sharpening and amplifying sounds

Question 16

inferior colliculi

Answer 16

the primary auditory centers of the
midbrain.
-paired grey matter structures of the dorsal midbrain that process auditory information

Question 17

tonotopic organization

Answer 17

are arranged in a map of low to high frequency

Question 18

primary auditory cortex (A1)

Answer 18

processes complex sounds transmitted from lower auditory pathways
-biologically relevant sound

Question 19

place coding

Answer 19

pitch is determined by the location of the activated hair cells

Question 20

temporal coding

Answer 20

encodes the frequency of auditory stimuli in the firing rate of auditory neurons

Question 21

binaural cues

Answer 21

If the ears are pointed in different directions or if the head
casts a sound shadow
-intensity differences: voume

Question 22

latency differences

Answer 22

arrival
o Onset disparity
o Ongoing phase disparity

Question 23

spectral filtering

Answer 23

the hills and valleys of the external ear alter the amplitude of some frequencies in a sound

Question 24

conduction deafness

Answer 24

disorders of the outer or middle ear prevent sounds from reaching the cochlea

Question 25

sensorineural deafness

Answer 25

hair cells fail to respond to movement of the basilar membrane; no action potentials fired

Question 26

central deafness

Answer 26

damage to auditory brain areas, such as by stroke, tumors, or traumatic brain injury
-word deafness: selective difficulty recognizing normal speech sounds
cortical deafness: difficulty recognizing all complex sounds, verbal or nonverbal

Question 27

vestibular system

Answer 27

sensory system that detects balance. consists of several small inner-ear structures that adjoin the cochlea
-semicircular canals
-ampulla

Question 28

semicircular canals

Answer 28

three fluid-filled tubes, connected to the utricle and saccule
o Canals (tubes) are oriented in three planes
of head movement:
 Nodding (pitch, y-axis)
 Shaking (yaw, z-axis)
 Tilting (roll, x-axis)

Question 29

ampulla

Answer 29

enlarged chamber at the base of
the canals; contains hair cells

Question 30

papillae

Answer 30

bumps on tongue, contain most of the taste receptors cells
-circumvallate
-foliate
-fungiform

Question 31

taste buds

Answer 31

embedded in the papillae, extend microvilli into
a pore where they can contact tastants

Question 32

salty

Answer 32

sodium (Na+) ions enter taste cells via sodium channels, causing depolarization
-a second salt sensor is TRPV1 which increases sensitivity to Na+ and also detects cations of other salts in food

Question 33

sour

Answer 33

-acids release hydrogen ions(H+) and taste sour
-sour taste cells seem to contain the same type of ion channel that allows an influx of protons, which depolarizes the cell
-the same receptor detects carbonation in drinks

Question 34

sweet, bitter, and umami

Answer 34

specialized receptors activate second messengers within the cell

Question 35

umami

Answer 35

meaty-savory flavor and is detected by two types of receptors
-metabotropic glutamate receptor that responds to glutamate
-receptor that is a combination of T1R1 and T1R3

Question 36

gustatory system

Answer 36

extends from the tongue, to brainstem nuclei, to the thalamus, and ultimately to the somatosensory cortex
-how we taste

Question 37

The auditory stimulus is transduced into electrical signals by the

Answer 37

hair cells

Question 38

olfaction

Answer 38

sense of smell

Question 39

olfactory epithelium

Answer 39

sense of smell start with receptor neurons in the nose- does the smelling
-supporting cells
-basal cells
-receptor neurons

Question 40

olfactory bulb

Answer 40

provides receptors for smell

Question 41

glomerulus

Answer 41

a complex arbor of dendrites from a group of olfactory cells; receives inputs exclusively from olfactory neurons that are expressing the same type of olfactory receptor

Question 42

vomeronasal system

Answer 42

detects pheramones

Question 43

pheramones

Answer 43

a chemical signal that is released outside the body of the animal and affects other members of the same species

Question 44

vomeronasal organ (VNO)

Answer 44

-humans don’t have one
a collection of specialized receptor cells that detect pheromones and send electrical signals to the accessory olfactory bulb in the brain