Neuro Anatomy 5 - Vestibular/ Auditory and Visual Pathways Flashcards
What bone are the organs of hearing and balance in the inner ear located in?
Temporal bone
What is the name of the bony canal within the petrous portion of the temporal bone that transmits nerves and vessels from within the posterior cranial fossa to the auditory and vestibular apparatus?
Internal acoustic meatus
How many turns does the cochlea make?
2.5
What is the name of the hearing transducing structure?
Organ of corti
What type of neurones in the cochlea are stimulated by hair cells?
Bipolar neurons
What is the name for the group of bipolar neurones at the cochlea which are stimulated by hair cells?
Spiral ganglion
Where does the spiral ganglion transmit action potentials from and to?
From organ of corti
To cochlear nuclei in medulla
Where does CN VIII enter the CNS?
Laterally on the pons-medullary junction
Where do first order neurones from the cochlea pass?
From the spiral ganglion to the ventral cochlear nucleus (via the cochlear nerve) in the medulla where they synapse
Where does the 1st order neurone of the auditory pathways synapse?
On ventral or dorsal cochlear nucleus in the medulla
What is the name for the structure formed when some of the 2nd order neurones of the auditory pathway cross?
Where is this?
Trapezoid body
Pons
Do signals from the cochlea pass up the ipsilateral/ contralateral side?
Travel up both sides (from the trapezoid body - pons)
Where do the 2nd order neurones of the auditory pathway synapse?
Some = superior olivary nucleus at pons
All (including those that have synapses at superior olivary nucleus) = inferior colliculus of midbrainb
Where is the next synapse of the auditory pathway after the inferior colliculus of the midbrain?
Medial geniculate body in the thalamus
What do the auditory neurones from the medial geniculate body in the thalamus travel via to reach the primary auditory area of the cerebral cortex?
Sublentiform part of the internal capsule
Where is the primary auditory area of the cerebral cortex located?
Superior temporal gyri
What is the word for any of the number of small swellings in the roof of the midbrain involved in vision and hearing?
Colliculus
What 2 nuclei are important in sound localisation and as relays for spatial and tensor tympani reflexes?
Superior olivary nucleus
Nucleus of lateral lemniscus
What is another name for the auditory association cortex?
Wernicke’s area
Where is Wernicke’s area located?
Posterior section of superior temporal gyrus
Where are fibres carrying information regarding low frequency sounds end within the auditory cortex?
Anterolateral part
Where do fibres carrying information regarding high frequency sound end in the auditory cortex?
Posteromedial part
What is aphasia?
Inability to se language
Where is Broca’s area?
Within the frontal lobe of the dominant hemisphere (usually left)
What functions does Broca’s area have?
Functions linked to speech production
What area is damage in Broca’s/ motor/ expressive aphasia?
Broca’s area
Describe Broca’s aphasia?
Patient has difficult in producing language, often using few words and only saying the most important words in a sentence
They do not usually have difficulty comprehending language
What area is damaged in Wenicke’s/ sensory/ receptive aphasia?
Wernicke’s area
Describe Wernicke’s aphasia?
Patient has difficult comprehending language
Patients can manifest defects ranging from words out of order to meaningless words