The Primary auditory receptive area is also known as ?
1) Anterior transverse gyrus
2) Heschl's gyri
What are 2 other names for the External Ear?
1) Pinna
2) Auricle
What is the name of the opening of the ear which leads inward toward the middle ear to the tympanic membrane?
External Auditory Meatus
The middle ear consists of?
The tympanic membrane and the the Ossicles
Give both names for all 3 ossicles
1) Malleaus or Hammer
2) Incus or Anvil
3)Stapes or Stirrup
The function of the footplate of the Stapes is?
To force the fluid of the cochlea backwards and forwards with every new sound.
Name the parts of the inner ear
1) Cochlea
2) Scali
3) Basilar Membrane
4) Organ of Corti
Which part of the ear contains hair cells that generate impulses?
The Semicircular Canal
True of False .. The Semcircular canal is not a part of the BAEP recording.
True .... The Semicircular canal is involved in the vestibular portion of the Acoustic Nerve
Name two parts of the ear besides the Semicircular canal that that are not involved in a BAEP recording, due to their vestibular function.
1) Utricle
2) Saccule
Name the 3 fluid filled parts of the cochlea.
1) Scala Vestibuli
2) Scala Media
3) Scala Tympani
Name in order the 7 parts of the cochlea.
1) Oval Window
2) Scala Vestibuli
3) Reissner's Membrane
4) Scala Media
5) Basilar Membrane
6) Scala Tympani
7) Round Window
What is the function of the Basilar Membrane?
It helps with sound recognition.
The thin firm end recognizes low frequencies and the broader more flexible end recognizes high frequencies.
What is the function of the Organ of Corti?
Located in the Scala Media.
The Organ of Corti changes electrical impulses for hair cells into nerve impulses that move through the cochlear nerve.
Wave I
The distal or extracranial portion of the auditory nerve
(8th Cranial Nerve)
Wave II
Generated as the auditory nerve enters the cranium at the medulla pontine junction and may be a proximal or intracranial portion of the auditory nerve in the cochlear nucleus
Wave III
It comes from the lower mid pontine level where the auditory nerve enters the brainstem between the medulla and Pons
It may correspond to action of the Superior Olivary Nucleus and the Trapezoid Body.
Wave IV
It is mostly from the mid to upper pontine level, contributions from the cochlear nucleus of the Lateral Lemniscus are probable as well.
A majority of the neurons decussate traveling through the trapezoid body to the superior olivary nucleus in the upper pons
Wave V
It comes from the fibers of the lateral lemniscus ending in the inferior colliculus. It is generated in the upper pontine level or by the inferior collicullus at the lower mid brain level.
Wave VI
It is generated in the Medial Geniculate Body. It is possibly due to continuous firing of the inferior colliculus.
Wave VII
It is generated in the auditory radiations. It is also possibly due to continuous firing of the inferior colliculous.
From here the signal goes to the primary auditory receptive area also known as Heschel's Gyri.
At how many weeks conceptional age may BAEPs be absent in normal premature infants?
30 weeks
Normal neonatal BAEPs have_________amplitude.
lower
In a normal neonate BAEP 1) wave I has a _______, 2) wave II has ___________, 3) wave III is _____ prominent and may be fused with _____, 4) latencies are _________
1. bifid peak
2. low amplitude
3. less
4. V
5. delayed
Amplitudes are typically ______ in children.
higher
What waves are difficult to identify when the rate is increased in children?
I and III
Which polarity is preferred in small children?
condensation
What is the most common cause of acquired sensorineural hearing loss in children?
meningitis
Middle ear infections cause what type of hearing loss?
conductive hearing loss
What types of things put children at risk for hearing loss?
1. meningitis
2. encephalitis
3. skull fracture
4. exposure to ototoxic medications
More than 1/2 of tumors in children age 2 and older appear in ____________.
the posterior fossa
In which waveforms will you see abnormalities in posterior fossas?
waves I and III
At what age is peripheral latency reached?
6 weeks old
At what age are adult central latencies reached?
18 months old
At what age are adult IPLs reached?
1 1/2- 2 years
At what age is adult morphology reached?
3-6 months
At what age are adult amplitudes reached?
5 years
On the Wave V latency-intensity graph, which type of hearing loss runs parallel to the normal hearing line?