Artefact Recognition And Diazepam In Electric Response Audiometry

Abstract

In measurements near auditory threshold, the influence of nonstationary artifacts (movement, swallowing, muscle activity, etc.) leads to response-like averaged results which should be further evaluated before determining the objective threshold. It is pointed out that, especially in recording VIII-nerve compound action potentials, as well as cortical potentials near threshold, the difference-amplitude histogram is a helpful procedure for identifying real neural responses.

Diazepam-induced reducation of amplitude of the averaged result observed in a few adults with relative weak response amplitudes leads to the conclusion that this was caused by a further increase of latency variability. It is also mentioned that a complex interplay exists between the influence of diazepam upon amplitude and latency variability of the single response, which sometimes may result in a peculiar response of the average (e.g., increase of both may result in no change of the average).

Key Words:

• Amplitude histogram
• Compound action potential
• Auditory eveked responses
• Latency variability