CSD 3103
ANATOMY OF SPEECH AND HEARING MECHANISMS
HOMEWORK
FOR THE INNER EAR
FALL SEMESTER 2008
DUE: September 29, 2008
Multiple
Choice
1. The auditory nerve is number
a) V
b) VI
c) VII
d) VIII
2. Crossover points uniting symmetrical portions
of the two halves
of the brain are called
a) tonotopic
b) decussations
c) neurons
d) none of the above
3. Fibers cross from the left cochlear nucleus
to the right cochlear
nucleus via the
a) trapezoid body
b) puperior
olivary complex
c) lateral lemniscus
d) inferior colliculus
4. The cochlear nucleus is divided into
a) superior and inferior
portions
b) left and right portions
c) dorsal and ventral portions
d) lateral and medial portions
5. Impulses are transmitted from the lower brainstem
to the inferior
colliculus by way of the
a) lateral lemniscus
b) medial geniculate
body
c) thalamus
d) auditory radiations
6. Heschl’s gyrus is located in the
a) brainstem
b) midbrain
c) thalamus
d) cortex
7. The first order auditory nerve fibers exiting
the cochlea are all
a) unipolar
b) bipolar
c) multipolar
d) nonpolar
8. Afferent refers to which direction of
travel?
a) nerve impulses from the ear
which are delivered to the brain
b) nerve impulses from the ear
which are delivered to motor neurons
c) nerve impulses from the brain
to sensory neurons of the ear
d) all of the above
9. Which of the following characteristics are
true of action potentials?
a) they are all-or-none
b) they are brought about by the
release of neurotransmitters
c) they are an electrical event
d) all of the abovength of the axon to another
Matching
|
_____1. |
The base of the brain where
it connects to the spinal cord |
a. Auditory nerve |
|
_____2. |
That part of the central
auditory pathway found in the midbrain |
b. Auditory radiations |
|
_____3. |
The VIII cranial nerve |
c. Brainstem |
|
_____4. |
The area of the pons that connects the ventral cochlear nucleus with the
lateral lemniscus on the other side of the brain |
d. Central nervous system |
|
_____5. |
Anatomical arrangement
according to the best frequency of stimulation |
e. Cerebellopontine
angle |
|
_____6. |
The area of the brain
receiving fibers from the ipsilateral cochlea by
way of the VIIIth cranial nerve |
f. Cochlear Nucleus |
|
_____7. |
Part of the auditory pathway
receiving fibers from the cochlear nucleus |
g. Decussation |
|
_____8. |
The superior temporal gyrus of the brain |
h. Heschl’s
gyrus |
|
_____9. |
Fibers in the temporal
cortex received from the medial geniculate body |
i. Inferior colliculus |
|
_____10. |
The crossing over of nerve
fibers from one side of the brain to the other |
j. Internal auditory canal |
|
_____11. |
The passage from the inner
ear to the brainstem containing the two branches of the VIII nerve, facial
nerve and internal auditory artery |
k. Lateral lemniscus |
|
_____12. |
The portion of the auditory
pathway running from the cochlear nucleus to the inferior colliculus
and medial geniculate body |
l. Medial geniculate body |
|
_____13. |
The brain and spinal cord |
m. Superior olivary complex |
|
_____14. |
The last subcortical
relay station, found in the thalamus |
n. Tonotopic
orcanization |
|
_____15. |
The junction at the base of
the brain where the cerebellum, medulla, and pons
communicate |
o.
Trapezoid body |
On the diagram below, find the
following:
Auditory Cortex Spiral Ganglion Brainstem
Inferior Colliculus Auditory Portion of
VIII N Temporal Gyrus
Trapezoid Body Single Auditory
Nerve Fibers
Auditory Radiations Dorsal Cochlear Nucleus
Ventral Cochlear Nucleus Medial Geniculate
Body
Lateral Lemniscus
Short Answer
5 pts. 2. Explain how the temporal pattern of the neural activity from a single auditory nerve fiber can represent or code frequency information from an incoming signal. (Hint: think about phase-locking behavior of the single fiber neurons). Now explain how the overall neural activity (spikes/s) from a single auditory nerve fiber can represent or code the intensity information arising from an incoming signal (Hint: think about the input-output functions of single auditory nerve fibers).