Half-sine stimuli and wave I of the ABR

The relation between half-sine stimuli and wave I of the ABR was explored in this initial study. Electrical half-sines in both polarities at the nominal frequencies 1,000, 2,000, 4,000 and 8,000 Hz were fed through a TDH-39 phone into KEMAR, an acoustic maniken designed to reproduce the acoustic transformations of a representative pinna, ear canal and eardrum. The same electrical waveforms through the TDH phone (at a peak equivalent level of 90 dB SPL) were then used to elicit ABRs in 4 normal hearing young adult listeners. Comparisons between the acoustic waveforms and ABR wave I showed that (1) the initial condensation peaks were excitatory, and (2) wave I latency differences resulting from half-sines of the same frequency in opposite polarity appeared consistent with the timing differences between the initial condensation peaks of the opposed half-sines.