15. The Special Senses

A progressive disorder characterized by the loss of higher-order cerebral functions is

(a) Parkinson's disease

(b) Parasomnia

(c) Huntington's disease

(d) Alzheimer's disease

A reduction in sensitivity in the presence of a constant stimulus is

(a) Transduction

(b) Sensory coding

(c) Line labeling

(d) Adaptation

Which of the following statements does not correctly describe the spiral organ?

a. Sounds of high frequency stimulate hair cells at the basal end.

b. The 'hairs' of the receptor cells are embedded in the tectorial membrane.

c. The basilar membrane acts as a resonator.

d. The more numerous outer hair cells are largely responsible for our perception of sound.

Pitch is to frequency of sound as loudness is to

a. Quality

b. Intensity

c. Overtones

d. All of these

Sound waves are converted into mechanical movements by the

(a) Auditory ossicles

(b) Cochlea

(c) Oval window

(d) Round window

(e) Tympanic membrane

The spiral organ is located in the_______of the internal ear.

(a) utricle

(b) bony labyrinth

(c) vestibule

(d) cochlea

Identify the structures of the external, middle, and internal ear in the following figure.

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a. ___

b. ___

c. ___

d. ___

e. ___

f. ___

g. ___

h. ___

i. ___

Auditory information about the frequency and intensity of stimulation is relayed to the CNS over the cochlear nerve, a division of cranial nerve

(a) IV

(b) VI

(c) VIII

(d) X

Displacement of stereocilia toward the kinocilium of a hair cell

(a) Produces a depolarization of the membrane

(b) Produces a hyperpolarization of the membrane

(c) Decreases the membrane permeability to sodium ions

(d) Increases the membrane permeability to potassium ions

(e) Does not affect the membrane potential of the cell

Damage to the ampullary cupula of the lateral semicircular duct would interfere with the perception of

(a) The direction of gravitational pull

(b) Linear acceleration

(c) Horizontal rotation of the head

(d) Vertical rotation of the head

(e) Angular rotation of the head

The malleus, incus, and stapes are the tiny bones located in the

(a) External ear

(b) Middle ear

(c) Internal ear

(d) Membranous labyrinth

What are the three auditory ossicles in the middle ear, and what are their functions?

The basic receptors in the internal ear are the

(a) Utricles

(b) Saccules

(c) Hair cells

(d) Supporting cells

(e) Ampullae

Sounds entering the external acoustic meatus are eventually converted to nerve impulses via a chain of events including:

a. Vibration of the eardrum

b. Vibratory motion of the ossicles against the oval window

c. Stimulation of hair cells in the spiral organ of Corti

d. Resonance of the cupula

Which of the following are paired incorrectly?

a. Cochlear duct—cupula

b. Vestibule—macula

c. Ampulla—otoliths

d. Semicircular duct—ampulla