Chapter 22 Auditory Pathways Flashcards
VIII was once called the auditory nerve because it is the nerve of _____________.
hearing
Many anatomists objected to calling VIII the ___________ nerve because it serves the function of hearing as well as the function of ____________.
auditory
balance
The central processes of __________ _____ __________ in the vestibular ganglion and the spiral ganglion of the cochlea synapse on neurons in the nuclei of VIII.
primary sensory neurons
VIII is now called the vestibulocochlear nerve because it carries information from the ______________ ganglion and the spiral ganglion of the __________.
vestibular
cochlea
Although some mnemonics still refer to VIII as the ____________ nerve, VIII is formally called the ___________________________ nerve.
auditory
vestibulocochlear
The vestibulocochlear nerve enters the _________________ at the border between the medulla and the pons.
brainstem
The vestibulocochlear nerve is assigned to the medulla although 1/3 of its nuclei are in the lower ____.
pons
Four nuclei of VIII are in the ___________, and 2 nuclei of VIII are in the ______.
upp medulla
lower pons
Most of the nuclei of the vestibulocochlear nerve that are assigned to the upper medulla extend a short distance into the lower _______, and one nucleus assigned to the lower pons extends a short distance into the upper _____________.
pons
medulla
The dorsal and ventral cochlear nuclei and the inferior and medial vestibular nuclei of VIII are in the upper medulla; the lateral and superior vestibular nuclei of VIII are in the ___________ _______.
lower pons
The dorsal cochlear nucleus is in the _________ ____________ dorsolateral to the inferior cerebellar peduncle.
upper medulla
The dorsal cochlear nucleus is ________________ to the inferior cerebellar peduncle.
dorsolateral
The dorsal cochlear nucleus is in the ___________ _____________between the ____________ ________________ ____________ and the lateral aperture of the 4th ventricle.
upper medulla
inferior cerebellar peduncle
The ventral cochlear nucleus is in the ___________ _______________ anterior to the dorsal cochlear nucleus.
upper medulla
Auditory information reaches the ipsilateral ventral (anterior) and dorsal (posterior) cochlear nuclei of the medulla in the cochlear division of the _________________________ nerve.
vestibulocochlear
The spiral ganglion of the cochlea sends auditory information to the ipsilateral ___________ and _________ _____________ nuclei.
dorsal
ventral cochlear
The central processes of the axons of spiral ganglion cells branch with the ventral branch synapsing in the ipsilateral __________ ___________ __________ and the dorsal branch synapsing in the ipsilateral __________ ___________ ___________.
ventral cochlear nucleus
dorsal cochlear nucleus
Each sound frequency is detected in a specific spot in the cochlea, and each sound frequency synapses in a specific spot in the ______________ dorsal cochlear nucleus, and each sound frequency synapsing in 3 specific spots in the ______________ ventral cochlear nucleus.
ipsilateral
ipsilateral
The dedication of a linear array of places to specific sound frequency/pitch is called
tonotopic organization (Greek: tono=tone, topos=place)
The dorsal cochlear nucleus and each of the 3 parts of the ventral cochlear nucleus have independent ________________ organizations.
tonotopic
Tonotopic organization is preserved in the projections of the __________ and __________ ___________ nuclei.
dorsal
ventral
cochlear
Thus _________________ organization is preserved in all pathways from the cochlea to the nucleus of the inferior colliculus in the lower midbrain.
tonotopic
The nucleus of the inferior colliculus is inside the ____________ ______________ in the ________ midbrain.
inferior colliculus
lower
Directly or indirectly, each nucleus of the ____________ _____________ receives tonotopically organized information from both dorsal cochlear nuclei and both ventral cochlear nuclei.
inferior colliculus
Auditory information from the dorsal and ventral cochlear nuclei reaches the nucleus of the inferior colliculus through the
lateral lemniscus.
Some projections of the dorsal and ventral cochlear nuclei to the __________ of the ____________ _______________ are direct.
nucleus inferior colliculus
Indirect projections of the dorsal and ventral cochlear nuclei to the nucleus of the inferior colliculus are relayed by the ____ in the lower pons and the ___ at the mid-pontine level.
lower: superior olivary complex
mid: nucleus of the lateral lemniscus
Some auditory information relayed to the ___________ ___ _____ ___________ ______________ from the dorsal and ventral cochlear nuclei crosses from left to right and vice-versa one to four times.
nucleus of the inferior colliculus
The first crossing of auditory information is between the ______ and the ____ of the lower pons.
ventral cochlear nucleus
superior olivary complex
The second crossing of auditory information is between the ____________ __________ ____________ of the lower pons and _____ in the mid-pons
superior olivary nucleus
nucleus of the lateral lemniscus
The third crossing of auditory information is between the ___________ of the ___________ _________________ in the mid-pons and the nucleus of the inferior colliculus.
nuclei lateral leminiscus
Some auditory information crosses from the nucleus of the lateral lemniscus to the _______________ nucleus of the inferior colliculus and some information crosses from one nucleus of the lateral lemniscus to the _______________ nucleus of the lateral lemniscus.
contralateral
contralateral
Because the nuclei of the lateral lemniscus are at the same level, their projections to each other are called a ________________.
commissure
The ________________ of the __________ _____________ is at the mid-pontine level.
commissure lateral leminisci
The final crossing of auditory information is the _______________ of the inferior colliculi in which the nuclei of the inferior colliculi project to each other.
commissure
The nuclei of the auditory system can detect the direction to the source of a sound by comparing the time delay between the arrival of information from the __________ and the ________.
right
left ears
Because the _____________ _____________ ____________, the ____________ of the ___________ _______________, and the ___________ of the _____________ _______________ receive both crossed and uncrossed auditory information, all can participate in detecting the source of a sound.
superior olivary complex
nuclei lateral lemniscus
nuclei inferior colliculus
The nucleus of the inferior colliculus receives information directly or indirectly from both _________ of the ___________ ____________, both __________ ___________ ______________, and both _____________ ___________, but it projects to only the ipsilateral medial geniculate nucleus of the thalamus.
nuclei lateral lemniscus
superior olivary complexes
cochlear nuclei
The nucleus of the inferior colliculus projects to the ipsilateral __________ _______________ ___________ of the thalamus through the brachium of the inferior colliculus.
medial geniculate nucleus
The medial geniculate nucleus of the _____________ receives information from the ipsilateral ____________ of the ___________ _______________ through the ____________ of the ___________ _____________.
thalamus
nucleus inferior colliculus
brachium inferior colliculus
Due to the many crossings of auditory information in the brainstem, each medial geniculate nucleus is conscious of sound in _________ ears.
both
Each medial geniculate nucleus is conscious of sound in both ears even ‘though it receives projections from only the ipsilateral ____________ of the ___________ _____________.
nucleus inferior colliculus
The medial geniculate nucleus receives projections from the _______________ nucleus of the inferior colliculus through the ___________ of the ____________ ______________.
ipsilateral
brachium inferior colliculus
