Sound and balance physiology Flashcards
Movement of the tympanic membrane causes…
Movement of the auditory ossicles against the oval window of the cochlea
Movement of stapes at the oval window causes…
pressure waves to be established in the perilymph of the cochlea
Pressure waves within the perilymph travel to…
the round window
How is information about frequency gained?
Sounds of different frequencies maximally distort the basilar membrane at different points- this allows information about sound to be converted to information about position
How is information on the intensity of sound gained?
Number of hair cells which depolarise
Vibration of the basilar membrane causes…
Hair cells to vibrate against the tectorial membrane, causing depolarization of hair cells
How is information about frequency and intensity of sound conveyed to the CNS?
Via the cochlear branch of CN VIII.
Where do sensory neurones from the cochlea synapse?
Cochlear nucleus
From the cochlear nucleus, where does sound information go?
Superior olivary nucleus of the pons
Inferior colliculus of the midbrain
Function of the superior olivary nucleus
localization of sound
Function of the inferior colliculus
direct a variety of unconscious motor responses to sound
Where in the thalamus does ascending sensory information synapse?
Medial geniculate nucleus
In what sense is the primary auditory cortex a “map” of the Organ of Corti?
Information about high-frequency and low-frequency sounds are delivered to particular segments of the cortex
