EDT Evoked Potentials 2

Question 1

Which wave in brainstem auditory evoked potentials (BAEPs) is thought to originate near the inferior colliculus and lateral lemniscus?

Accepted Answer

Wave V

Answer

Wave V is the largest and most reliable BAEP component and is generated in the region of the lateral lemniscus and inferior colliculus in the midbrain.

Question 2

What is the approximate normal I-V interpeak latency in brainstem auditory evoked potentials?

Accepted Answer

4.0 ms

Answer

The I-V interpeak latency normally measures approximately 4.0 ms and reflects total conduction time through the brainstem auditory pathway from the cochlear nerve to the midbrain.

Question 3

Prolonged P100 latency with preserved amplitude in VEPs is most characteristic of which pathological process?

Accepted Answer

Demyelinating disease such as multiple sclerosis affecting the optic nerve

Answer

Demyelination slows axonal conduction velocity, delaying the P100 latency while the amplitude may remain normal because axons are structurally intact.

Question 4

The popliteal fossa potential in tibial nerve SSEP recordings serves which primary purpose?

Accepted Answer

Confirming peripheral nerve activation proximal to the stimulation site

Answer

The popliteal fossa electrode records the tibial nerve action potential as it passes behind the knee, confirming the peripheral pathway is intact before the spinal cord segment.

Question 5

Which click stimulus polarity is most commonly used clinically for BAEPs to minimize stimulus artifact?

Accepted Answer

Alternating polarity

Answer

Alternating polarity cancels the cochlear microphonic and reduces stimulus artifact by averaging responses to opposite-polarity clicks, preserving the neural response.

(EDT) Electrodiagnostic Technician Certification Practice Test

(EDT) Electrodiagnostic Technician Certification Practice Test

EDT Evoked Potentials 2