Unit 3: Audition Flashcards
L1: _____ of sound is encoded by the frequency of afferent nerve fiber action potentials
Intensity
L1: _____ of sound is encoded by the position along the cochlea where the afferent nerve fiber innervates the IHC.
Frequency
L1: ______ rely on the spatial separation of ears and direction-dependent differences in path lengths to localize sounds.
Interaural time delays
L1: At the ____ of the cochlea, the basilar membrane is thinner, narrower, and more rigid.
base
L1: At the ____ of the cochlea, the basilar membrane is wider, thicker, and more flexible.
apex
L1: Depolarization of IHCs leads to release of ____ to signal an afferent nerve fiber.
glutamate
L1: In the primary auditory cortex, neurons representing ____ frequencies are located more anteriorly.
lower
L1: Influx of _______ occurs during mechanosensitive depolarization of IHCs.
potassium
L1: Interaural level differences are used for effective localization of ______-frequency sounds.
High
L1: Interaural time delays are used for effective localization of _____-frequency sounds.
Low
L1: Ototoxic medications often inhibit transduction channels of _______, which eventually kills them.
OHCs
L1: Span of human hearing
20-20,000 Hz
L1: The ____ of the cochlea responds best to high frequencies.
Base
L1: The ____ of the cochlea responds best to low frequencies
Apex
L1: The apex of the cochlea responds best to ______ frequencies.
Low
L1: The base of the cochlea responds best to ______ frequencies.
High
L1: The majority of hair cells in the cochlea are _______.
Outer hair cells
L1: The primary auditory cortex is Brodmann area ___, and the secondary cortex including Wernicke’s area is Brodmann area ___.
41, 42
L1: When the stereocilia bundle is displaced toward the longest stereocilia, _______ is elicited.
depolarization
L1: When the stereocilia bundle is displaced toward the shortest stereocilia, _______ is elicited.
hyperpolarization
L2: _____ is a localization mechanism that relies on phase-locking.
Interaural time delays
L2: ______ neurons sense frequency and intensity and provide efferent innervation to OHCs.
Medial Olivocochlear (MOC)
L2: _______ encoded in the dorsal cochlear nucleus is useful for elevation localization.
Monoaural spectral shape
L2: ________: creation of sounds by evoked or spontaneous movements of OHCs that set the basilar membrane in motion; used to test newborn hearing
Otoacoustic emissions
L2: _______: a ____-rich fluid that fills the scala media
endolymph; potassium
L2: At the level of the _______, neurons are encoding auditory information for the contralateral ear.
inferior colliculus
L2: Cochlear amplifier: displacement of the ______ by the ____.
basilar membrane; OHCs
L2: Decussated DCN and VCN cells regroup in the ________ and ascend to the _______.
Lateral lemniscus; inferior colliculus
L2: Dorsal cochlear neurons decussate via the _______.
Dorsal acoustic stria
L2: Downward movement of the ________ compresses fluid in the ________, which causes an outward bulging of the round window;
basilar membrane; scala tympani
L2: Inferior colliculus neurons innervate the _______.
Ipsilateral Medial Geniculate Nucleus, Contralateral Medial Geniculate Nucleus, Contralateral inferior colliculus
L2: Interaural level differences are processed in the ______.
Lateral superior olive
L2: Interaural time delays are processed in the _______.
Medial superior olive
L2: Lateral superior olive neurons project to the _______ and _______.
ipsilateral dorsal nucleus of the lateral lemniscus (DNLL), ispsilateral inferior colliculus
L2: Mechanisms of overcoming acoustic impedance mismatch (2)
Area of stapes foot, levering action of incus/malleus
L2: Medial superior olive neurons send excitatory afferents to the ____ and ______.
ipsilateral dorsal nucleus of the lateral lemniscus (DNLL), ispsilateral inferior colliculus
L2: MTNB neurons are ____-ergic, providing ______ input on the lateral superior olive.
glycin; inhibitory
L2: Regions of the auditory cortex are connected via the ______ and _______.
association fibers, anterior commissure
L2: The _______ pumps potassium ions into the scala media to maintain an endocochlear potential of _____.
stria vascularis; +80 mV
L2: The basal end of the hair cell is bathed in a fluid called ______.
perilymph
L2: The lateral superior olive receives ipsilateral input from the ______.
Anteroventral cochlear nucleus
L2: The medial geniculate nucleus sends axons to the _______, located in the _______.
Primary auditory cortex (A1); superior temporal gyrus
L2: Ventral cochlear neurons decussate via the _______.
Trapezoid body
L2: When the stapes is pressed on the _______, the fluid in the ________ is compressed
oval window; scala vestibuli
L3: ____ of ANFs are myelinated and innervate _______. (Type ___
95%; IHCs; I
L3: ____ of ANFs are unmyelinated and innervate ______. (Type __)
5%; OHCs; II
L3: ANFs have cell bodies in the _______ and innervate the ______ and _______.
Spiral ganglion; dorsal cochlear nucleus, ventral cochlear nucleus
L3: The inferior colliculus receives auditory fibers from the ______ and ______.
Cochlear nuclei, pontine nuclei (superior olivary complex)
L3: The lateral superior olive receives contralateral input from the ______.
Medial nucleus of the trapezoid body (MNTB) from the AVCN
