Chapter 16- Hearing

Question 1

Components of the External Ear

Answer 1

Pinna: changes in size, shape, flexibility and hair growth
Auditory canal: covered by skin and lined with hair follicles and cerumen producing glands

Question 2

What age-related changes occur to the Cerumen?

Answer 2

• Increased in concentration of keratin
• The growth of longer and thicker hair (especially in men)
• Thinning and drying of the skin lining the canal—can cause it to build up.
• An age-related decrease in sweat gland activity further increases the potential for cerumen to
  accumulate by making the cerumen drier and more difficult to remove.

Question 3

Components and function of the Middle ear

Answer 3

The tympanic membrane is a transparent, pearl-grey, slightly cone-shaped layer of flexible tissue, which separates the outer and middle ear.
* Its primary functions are to transmit sound energy

Question 4

Age-related changes to the Middle ear

Answer 4

• With increased age, collagenous tissue replaces the elastic tissue, resulting in a thinner and stiffer eardrum.
• With increased age, the middle ear muscles and ligaments become weaker and stiffer.

Question 5

Age-related changes to the Inner ear

Answer 5

loss of hair cells, reduction of blood supply, degeneration of spiral ganglion cells and loss of neurons in the cochlear nuclei.
* The degenerative changes of the cochlea and other inner ear structures are the primary cause of the age-related HEARING IMPAIRMENT

Question 6

The auditory nervous system is affected by all the following age-related changes:

Answer 6

• Degenerative changes in the inner ear
• Narrowing of the auditory meatus
• Diminished blood supply and central nervous system changes.

Question 7

What is the leading cause of hearing loss?

Answer 7

Impacted cerumen (ear wax)

Question 8

What are ototoxic medications?

Answer 8

Ototoxicity is defined as the toxic effect on the functioning of the inner ear, which may lead to temporary or permanent hearing loss and balancing problems. Drugs or pharmaceutical agents inducing ototoxicity are regarded as ototoxic medications.

Question 9

What is Otosclerosis?

Answer 9

• A hereditary disease that affects the bones in the middle ear.
• Disruptions in the transmission of sound waves to the inner ear (Abnormal bone growth in the stapes- This impacts the normal movement of ossicles)
• Onset in youth/early adulthood
• hearing loss may not be detected until middle/later adulthood when age-related changes compound the disease-related changes.

Question 10

What are the symptoms/effect of Otoscleorosis

Answer 10

• Otosclerosis primarily causes a conductive hearing loss, but some sensorineural loss may also occur.
• Initially symptom: difficulty heairng soft and low-pitched sounds
• Later: hearing loss worsens with dizziness, tinnitus or balance problems.

Question 11

Ménière disease

Answer 11

Build up of fluid in inner ear.
-Acoustic neuromas (tumor
along vestibulocochlear nerve) commonly cause hearing impairment.

Question 12

Conductive vs Sensorineural hearing loss (and mixed)

Answer 12

Conductive hearing loss:
abnormalities of External
and Middle ear interfering
with sound conduction

Sensorineural hearing loss:
abnormalities of sensory
and neural structures of
Inner ear, usually age
related or noise induced

Mixed hearing loss:
involves both conductive
and sensorineural impairments

Question 13

Effects on Communication:
Conductive hearing loss

Answer 13

Reduced intensity of sounds and difficulty hearing vowels and low-
pitched tones.
* Occurs in one or both ears
* Often there is a history of otosclerosis, perforated eardrum or other ear disease

Question 14

What is Presbycusis?

Answer 14

Sensorineural hearing loss - age-related degeneration of the auditory structures
* Usually occurs in both ears and can vary

Question 15

Functional consequences of Presbycusis

Answer 15

Early: loss of ability to hear high-pitched sounds and sibilant consonants.
* When high-pitched sounds are filtered out, words become distorted and jumbled, and sentences become incoherent

• Diminished speech discrimination is influenced by the speaker’s rate of speech: rapid,
  slow or slurred speech patterns make it increasingly difficult for the older person to discern words.
• As the hearing loss progresses, explosive consonants, such as b, d, k, p and t, also become distorted.
• Background noise and environmental conditions, compound the effects of sensorineural hearing loss and can interfere with the
  ability to recognize words, even in the absence of a significant hearing loss.

Question 16

Tinnitus

Answer 16

• persistent sensation of ringing, roaring, blowing and buzzing
  It is A SYMPTOM
• Associated with hearing loss, ototoxic medications and Ménière disease
• Exacerbated with caffeine, alcohol or nicotine