chapter 9 (M. Wolfe)

Question 1

acoustic reflex

Answer 1

A reflex that protects the ear from intense sounds, via contraction of the stapedius and tensor tympani muscles.

Question 2

afferent fiber

Answer 2

A neuron that carries sensory information to the central nervous system.

Question 3

amplitude or intensity

Answer 3

The magnitude of displacement (increase or decrease) of a sound pressure wave. Amplitude is perceived as loudness.

Question 4

audibility threshold

Answer 4

The lowest sound pressure level that can be reliably detected at a given frequency.

Question 5

auditory nerve

Answer 5

A collection of neurons that convey information from hair cells in the cochlea to (afferent) and from (efferent) the brain stem.

Question 6

characteristic frequency (CF)

Answer 6

The frequency to which a particular auditory nerve fiber is most sensitive.

Question 7

cochlea

Answer 7

A spiral structure of the inner ear containing the organ of Corti.

Question 8

cochlear nucleus

Answer 8

The first brain stem nucleus at which afferent auditory nerve fibers synapse.

Question 9

efferent fiber

Answer 9

A neuron that carries information from the central nervous system to the periphery.

Question 10

equal-loudness curve

Answer 10

A graph plotting sound pressure level (dB SPL) against the frequency for which a listener perceives constant loudness.

Question 11

fundamental frequency

Answer 11

The lowest-frequency component of a complex periodic sound.

Question 12

harmonic spectrum

Answer 12

The spectrum of a complex sound in which energy is at integer multiples of the fundamental frequency.

Question 13

hertz (Hz)

Answer 13

A unit of measure for frequency. One equals one cycle per second.

Question 14

inferior colliculus

Answer 14

A midbrain nucleus in the auditory pathway.

Question 15

frequency

Answer 15

For sound, the number of times per second that a pattern of pressure change repeats. Perceived as pitch.

Question 16

medial geniculate nucleus

Answer 16

The part of the thalamus that relays auditory signals to the temporal cortex and receives input from the auditory cortex.

Question 17

organ of Corti

Answer 17

A structure on the basilar membrane of the cochlea that is composed of hair cells and dendrites of auditory nerve fibers.

Question 18

ossicle

Answer 18

Any of three tiny bones of the middle ear: malleus, incus, and stapes.

Question 19

primary auditory cortex (A1)

Answer 19

The first area within the temporal lobes of the brain responsible for processing acoustic information.

Question 20

rate saturation

Answer 20

The point at which a nerve fiber is firing as rapidly as possible and further stimulation is incapable of increasing the firing rate.

Question 21

sine wave or pure tone

Answer 21

The waveform for which variation as a function of time is a sine function.