Effects of stimulus phase on the latency of the auditory brainstem response.

Auditory brainstem responses were measured in five normal-hearing subjects, using single-cycle sinusoids at octave frequencies ranging from 250 to 2000 Hz. These sinusoids, gated with Blackman functions, were presented either at 0 or 180 degree phase and were varied in level from 90 dB SPL to threshold in 10-dB steps. Stimulus phase affected wave V latencies for low-frequency stimuli, with the effect decreasing as frequency increased. These data are thought to represent an evoked potential manifestation of known phase-locking abilities within the auditory system.