Auditory Flashcards
What is the brief anatomy of the ear?
Outer ear—> tympanic membrane —-> ossicles—> cochlea
what is the brief anatomy of the middle ear? What is the function of the stapes?
Mallelous–> Incus–> Stapes (transfer air into moving the fluid in cochlea)
In a cross section of the cochlea, what are the 3 main structures? What is in the middle, and what is it composed of?
Scala Vestibuli, Scala Media, and scala tympani. Organ of Corti is underneath Scala Media but above Scala tympani. Organ of corti consists of outer and inner hair cell with tectorial membrane on top and basilar membrane on bottom
What is the function of the typlinks?
amplify the forces
Outer hair cells recieve ______ output whereas inner hair mainly recieve _____ output
efferent, afferent
High frequencies are encoded into the ____ of cochlea whereas low frequencies are encoded into the ___ of cochlea
base, apex
Hair cells are stimulated by the _____ between tectorial and basilar membrane
shearing force
Upward phase of the shearing force means ___i of hair cell and downward phase is _____ of hair cell
depolarisation, repolarisation
Apical portion of hair cell is bathed in ____ whereas basal portion of hair cell is ____ in K+
K+, deficient
Describe the mechanoelectrical transduction which is mediated by hair cells
In hair cell, K+ is high outside cell and the K+ channels in cilia tips respond to mechanical forces, K+ goes inside cell, causing depolarisation. This then opens Ca+ channels in the basal end of cell, leading to vesicular neurotransmitter to stimulate nerve. Pottasium then flows out of cell.
Cortical representation of auditory information is _____
tonotopic
The auditory pathway is essentially ______ beyond the cochlear nucleus. Tonotopy is preserved in the _______ and _____
A) Unilateral, central auditory nuclei, auditory cortex
B) Bilateral, central auditory nuclei, auditory cortex
C) Bilateral, central auditory ganglia, auditory cortex
D) None of the above
B)
The Eustation tube allows?
equalisation of pressure across the tympanic membrane.
the scala vestibuli and scala tympani have ___ potassiumion concentration), separated by the cochlear duct (scala media which has ____potassium ion concentration
A) low, high
B) high, low
C) low, low
D) high, high
A) low, high
