Central auditory dysfunction: qEEG correlates of individual differences in ear advantages and REP/ABR results.

Abstract

A new test battery for central-auditory diagnostics, supplementing standard audiometry with MacCAD (a Macintosh-based program for central auditory diagnostics), and the ABR version of our repeated-evoked potentials (REPs) protocol, was described to the Spring 1991 meeting of this Society. As reported then, preliminary results distinguished among a variety of patients, with some details predictive of individual patterns of supra-brainstem involvement. Subsequent testing of the same subjects using quantitative EEG provides initial support for these predictions. For example, in one subject originally diagnosed as ‘‘central auditory,’’ previous findings such as ‘‘polar-opposite’’ ear advantages and ‘‘release signs’’ in ABR stability profiles, were accompanied by qEEG characteristics such as reduced beta power over auditory cortex bilaterally, and diminished interhemispheric coherence. Similar findings in other subjects suggest that by exploiting the sensitivity of repeated-measures test designs to individual characteristics, it may be possible to generate more detailed physiological and behavioral profiles of central auditory function.