neural pathways in hearing (cochlear branch) Flashcards
what do cochlear nerve fibres make dendritic contact with
hair cells of the organ of corti
within the cochlear duct
what is the spiral ganglion
the cell bodies of cochlear nerve fibres which lie within the cochlea
where does the cochlear nerve join the brainstem
at the level of the rostral medulla
where do cochlear nerve fibres bifurcate and end
in the dorsal & ventral cochlear nuclei, which lie close to the inferior cerebellar peduncle
from the cochlear nuclei, where do the second-order neurones ascend into
into the pons where the fibres travel to the superior olivary nucleus
what is the function of fibres in the superior olivary nucleus
the fibres leave the brainstem in the
vestibulocochlear nerve and end in the organ of corti
- serve an inhibitory function
- serve to adjust transmission of auditory information through the
cochlear nerve by mediating contractions of the tensor tympani and stapedius in response to loud noises
where do superior olivary nucleus fibres travel to from the superior olivary nucleus
to the inferior colliculus of the
midbrain
what carries auditory info from the inferior colliculus of the midbrain
the inferior brachium (nerve fibre) carries the auditory information to
the medial geniculate body of the thalamus
where does auditory info go from the medial geniculate body
fibres travel through the internal capsule to the primary auditory cortex of the temporal lobe - situated on the dorsal surface of the superior temporal gyrus
what is Wernickes area
the region of the temporal lobe surrounding the primary auditory cortex
it is where auditory information is interpreted and understood
where is Wernicke’s area
in the superior temporal
lobe
what is Wernicke’s area important for
in the processing of language in the brain
what happens if Wernicke’s area is damaged
a patient will not be able to understand
questions and their speech will be incomprehensible
Summary of path of cochlear branch of vestibulocochlear nerve (CNVIII)
- Cochlear nuclei
- Superior olivary nucleus
- Inferior colliculus
- Medial geniculate body - via the inferior brachium (nerve)
- Primary auditory cortex, in Wernicke’s area
what does the the chorda tympani (branch of the facial nerve CNVII) do
conveys taste information from the tongue and runs THROUGH THE MIDDLE EAR to carry taste messages to the brain
