Hearing and Balance Lecture

Question 1

Hearing is…

Answer 1

vibrational energy

Question 2

sound wave order

Answer 2

pinna (outer ear) > external acoustic meatus > tympanic membrane (ear drum) = vibration of the auditory ossicles > oval window >
> movement of fluid (perilymph) in scala vestibuli > movement of fluid (endolymph) in cochlear duct > hair cells in spiral organ bend = Action Potential -> Vestibulocochlear nerve > medulla oblongata > temporal lobe of cerebrum

Question 3

Chambers of the Cochlea

Answer 3

1. Upper Chamber
   - Scala Vestibuli; has fluid
2. Vestibular membrane
3. Cochlear Duct
   - Spiral Organ; has endolymph fluid

Question 4

What you hear can affect..

Answer 4

the Limbic system because the medulla oblongata is a part of of the ANS

Question 5

Organ of Corti is the same thing as

Answer 5

the Spiral Organ; hearing in the cochlea

Question 6

Deafness:
- causes

Answer 6

: hearing loss
1. Conduction Deafness: blockage of the sound waves
- causes; build up of ear wax, torn ear drum, otitis media, ostoscelerosis
- need a hearing AID to fix this issue

2. Sensorineural Deafness: nerve deafness (damage to neural tissue
   - causes; damage to the hair cells, exposure to loud sounds, damage to the cochlear nerve, stroke, tumor
   - usage of a cochlear implant is needed
3. Tinnitus: ringing in the ears, absence of stimuli is a result
   - from cochlear nerve damage OR side effect of medication, loud noise exposure

Question 7

Balance and Equilibrium

Answer 7

Internal ear, eyes, proprioceptors (sense stretch in ligaments/muscles/tendons
- less functional in increase in age

Question 8

Types of Equilibrium

Answer 8

1. Static Equilibrium: linear acceleration (standing, walking) due to the vestibule (includes utricle + saccule)
2. Dynamic Equilibrium: function of the semicircular canals (3 per/ear) involved with angular acceleration (spinning)
   - contains Crista Ampullaris

Question 9

Macula

Answer 9

a region in the utricle/sacule containing otoliths (calcium carbonate granules sit on a membrane that has hair cells in it)
- tilting of the head causes the otoliths hair cells to bend = initiates a nerve impulse
– enters the VC nerve > medulla > cerebellum OR frontal lobe

Question 10

Crista Ampullaris

Answer 10

made up of hair cells embedded in gel + part of the dynamic equilibrium
- within each canal it contains endolymph (fluid)
as the person spins the fluid moves causing bending of the hair cells = Action Potential >
> VC nerve > medulla > cerebellum or frontal lobe

Question 11

Motion Sickness:

Answer 11

: nausea, vomiting, dizzy, and loss of balance
- due to mismatch of sensory input
–ex: in a cruise you’re getting tossed back and forth you’re eyes and ears perceive DON’T match
- affects the ANS: by sweating, vomiting

Question 12

Menieres Syndrome

Answer 12

: affects the internal ear, disorder
- causes vertigo (loss of balance), nausea, vomiting
- results in the person not being upright

Question 13

Presbycusis:

Answer 13

: loss of the ability to hear high pitch sounds
- due to OLD age