Lecture 9: Sensory Tracts & Hearing

Question 1

What is hydrocephalus, why is it mostly only present in babies?

Answer 1

Build-up of CSF in ventricles due to stenosis. Usually only present in babies because fontanelles allow for stretching of the skull.

Question 2

Sound travels through the ________ ear until it hits the ___________ ________.

Answer 2

External, tympanic membrane

Question 3

Within the external ear, ___ traps foreign bodies and repels _______ through ___________ glands.

Answer 3

Wax, insects, ceruminous.

Question 4

What is the passageway of the external ear called?

Answer 4

External auditory canal

Question 5

What are the three ossicles that exit in the ear? What do they do?

Answer 5

Malleus, incus, stapes. Mechanical transmission of auditory sounds.

Question 6

What is the name of an ear infection that fills puss in the inner ear?

Answer 6

Otitis media

Question 7

The _____ _______ connects the middle ear to the inner ear.

Answer 7

Oval window.

Question 8

What are the types of noises heard throughout the cochlea?

Answer 8

Bass = center, mid = middle, treble = outside

Question 9

What does the tectorial membrane?

Answer 9

When the endolymph vibrates, it stimulates the tectorial membrane. This wiggles hairs inside, and sends a signal to the brain.

Question 10

After sound hits the tympanic membrane, the sound is transported through the _______.

Answer 10

Ossicles

Question 11

Ossicles vibrate the ______ ________.

Answer 11

Oval window

Question 12

When oval windows vibrate, the ________ is vibrated.

Answer 12

Endolymph

Question 13

Where does sound exit the cochlea?

Answer 13

The round window

Question 14

Which cranial nerve is responsible for hearing? Where is it sent?

Answer 14

Vestibulocochlear nerve, sent to the auditory cortex.

Question 15

What occurs during conductive hearing loss?

Answer 15

Reduction in sound amplitude, typically unilateral. Caused by tympanic membrane rupture, wax buildup, damage to ossicles, etc.

Question 16

What occurs during sensorineural hearing loss?

Answer 16

High tones affected, typically bilateral. Caused by trauma, prolonged nerves, tumors, drugs, etc.

Question 17

What is contained within the vestibular apparatus?

Answer 17

Utricle, saccule, 3 semi-circular canals (ant, post, lat).

Question 18

What are the utricle and saccule made of?

Answer 18

Supporting cells, otolith membranes, otolithic crystals, hairs

Question 19

What two canals make up the semicircular canals?

Answer 19

Ampulla and cupula

Question 20

The ampula is the _____ region containing ________ and _______.

Answer 20

Dilated, crista, endolymph

Question 21

The cupula is moved by _______ and bends ______ cells.

Answer 21

Rotation, hair

Question 22

The __________ and ____________ are responsible for hearing. The ___________ ___________ is responsible for balance.

Answer 22

Cochlea, spiral organ, vestibular apparatus

Question 23

What are the 5 sensory modalities?

Answer 23

Touch, pressure, proprioception (qual), temperature, pain (quan)

Question 24

What are dermatomes?

Answer 24

Areas of skin that rely on nerves that connect to spinal cord

Question 25

How do nerves travel up spine?

Answer 25

Posterior column, lateral spinothalamic tract

Question 26

What is the thalamus responsible for?

Answer 26

Selective attention, sensory integration/relay

Question 27

What is the dorsal column responsible for? The spinothalamic system?

Answer 27

Dorsal column = touch, pressure, proprioception. Spinothalamic = pain & temperature

Question 28

What are the two spinothalamic tracts?

Answer 28

2 synapses: spinal cord and thalamus

Question 29

What is the reticular formation?

Answer 29

Collection of gray matter within nervous system = pain modulation (oops, don’t do that again!)

Question 30

Where are the two synapses of the dorsal column?

Answer 30

Medulla, thalamus

Question 31

Through what does proprioception information travel through?

Answer 31

Ipsilateral cerebellum