Some parameters affecting Békésy audiometric thresholds.

Abstract

Bekesy automatic audiometric findings may be affected by various factors such as contralateral masking, starting frequency, starting level, exposure to stimulating sound and different stages of some disease entity. These findings are seen mostly on steady-tone tracings as revealed by peak-to-peak amplitude reductions and threshold drifts. This paper is concerned with automatic audiometry parameters which have been little known or ignored by many investigators. Detailed audiometric case histories from 6 patients with a variety of unilateral sensorineural hearing impairments showed, e.g., that contralateral masking in the normal ear can produce striking effects on tracings to steady-state tones in the affected ear. Various starting frequencies produced marked effects on separation between pulsed-and steady-tone tracings if hearing was tested starting at suprathreshold levels. A patient diagnosed as having an early endolymphatic hydrops retested within 1 hr following an episodic attack displayed varieties of findings. The automatic audiometric method demonstrates the interrelation of level and adaptation.