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What is frequency? How is it measured?
Frequency is the number of wave crests per second, measured in Hertz (Hz)
What is the function of the Eustachian tube?
Equalizes pressure in the middle ear.
What is presbycusis?
Age-related progressive hearing loss.
What is the job of an audiologist?
Perform hearing assessments, fit hearing aids, diagnose disorders, and educate on ear protection.
What is the difference between hearing aids and cochlear implants?
Hearing aids amplify sound; cochlear implants stimulate the auditory nerve.
Define masking and provide a real-world example.
Masking is when a louder sound makes a softer one inaudible; e.g., an airplane drowning out a conversation.
Name the structures of the outer ear. What are the protective mechanisms of the outer ear?
Pinna, conchal bowl, and external auditory meatus. Cerumen, hair follicles, and epithelial migration.
Describe Waardenburg Syndrome and its effect on hearing.
A genetic disorder affecting pigmentation and hearing due to cochlear encoding issues.
Why is the prevalence of hearing loss increasing globally?
Due to the growing number of seniors worldwide.
What is ABR testing, and what information does it provide?
Auditory Brainstem Response measures how sound travels through the auditory nerve to the brainstem.
Explain the 3 types of tympanogram results (Type A, B and C)
Type A=TM movement WNL
– Indicative of normal middle ear function
- peak at about 0
Type B=NO TM movement
– With normal ear canal volume, indicative of: Fluid in ME (most common) or Fixed ossicles
– With large ear canal volume, indicative of:Perforation in TM or Patent (open) PE tube
-flat line
Type C=TM retraction
– Indicative of Eustachian tube dysfunction
-peak at less than 0
Describe the role of the tympanic membrane and ossicles in the transmission of sound through the ear.
The tympanic membrane vibrates when sound waves reach it, and the vibrations are transmitted to the ossicles (malleus, incus, stapes). These ossicles amplify the sound and increase the pressure as the sound moves toward the inner ear.
What is EVA, and how does it relate to Pendred Syndrome?
Enlarged Vestibular Aqueduct; often found in Pendred Syndrome, causing progressive hearing loss.
What is hearing conservation? Why is it important?
Hearing conservation involves using protection and limiting loud noise exposure to prevent irreversible damage. Regular hearing tests and avoiding inserting objects into the ears are also key preventive measures.
Describe VRA and CPA behavioral tests.
VRA uses visual stimuli for children (6-24 months); CPA involves conditioned tasks for children (2-5 years).
Explain constructive and destructive interference.
Constructive: Waves combine to amplify sound. Destructive: Out-of-sync waves cancel each other out.
How is sound converted into an electrical signal within the cochlea?
Vibrations from the oval window create pressure waves in the cochlear fluid, disturbing the scala media and activating the hair cells in the organ of Corti. Outer hair cells amplify the sound, while inner hair cells convert it into an electrical signal sent to the brain via the cochlear nerve.
What is the difference between syndromic and nonsyndromic hearing loss.
Syndromic involves multiple symptoms (e.g., Goldenhar syndrome); nonsyndromic only affects hearing (e.g., Connexin 26).
Name one reason a child would be referred to an audiologist after a school hearing screening.
- 30dB HL or greater at 2 or more frequencies on 2 consecutive tests at least 2 and no more than 6 weeks apart*
-OR-
40dB HL or greater at 1 frequency on 2 consecutive tests at least 2 and no more than 6 weeks apart*
-OR-
Evidence of pathology
Referral for “medical-audiological” examination *CCS (CA Children’s Services – must be more than 6 weeks apart)
Define sound cancellation and resistance.
What is resonance, and give an example.
Resonance occurs when an object vibrates at its natural frequency, like a guitar amplifying string vibrations.
In your own words, describe how sound travels through the ear.
Sound waves are traveling through ambient air, the sound is either collected or deflected by the pinna. Sound that is collected travels into the concha bowl and down the external auditory meatus, where the sound resonates. When the soundwave reaches the end of the EAM it hits and vibrates the tympanic membrane. Attached the the TM is the malleus, the first and largest of the three ossicles, travels through the incus and stapes, during this process the sound is being amplified and pressure is being increased. When the sound reaches the end of the stapes, it will vibrate the oval window, another thin membrane separating the middle and inner ear. The sound wave hits the oval window causing a vibration of fluid in the cochlea. The first and last chamber in the cochlea: scala vestibuli and scala tympani, are the first to experience a distribution in fluid. These pressure waves cause a disturbance in the scala media, the middle chamber that contains the basilar membrane and organ of corti. Here the outer hair cells are activated, they amplify and transmit the sound to the inner hair cells where the sound is encoded into an electrical signal, this signal is send up through the cochlear nerve to the brain, where the brain finally decodes the information and we have an auditory experience.
What are cochlear aplasia and Michel’s aplasia?
Congenital malformations causing complete absence of the cochlea (cochlear aplasia) or the entire inner ear (Michel’s aplasia).
Name one difference between a screening and a diagnostic test.
Screening:
-Test large numbers of subjects
-Test simply and efficiently
- Detect indicators of HL for referral
Diagnostic Testing:
-Test specific individuals identified at risk
-Test in detail and at a greater cost
-Establish the presence or absence of HL / definitive diagnosis
What is FM/DM technology, and how does it help hearing aid users?
It uses radio signals to transmit sound, improving speech clarity in noisy environments.