CONCURRENT RIGHT AND LEFT EAR AUDITORY BRAIN-STEM RESPONSE RECORDING

In auditory brain stem response testing, it is often advantageous to r ecord the responses to right and left ear stimulation quickly. A metho d is described in which both ears are tested concurrently, each ear at a slightly different stimulus rate. With appropriate temporal paramet ers, the response of each ear can be recorded without contamination by the contralateral ear's response. When both ears were tested at the s ame intensity, either 40 or 70 dB nHL, there was little attenuation of wave V. When one ear was stimulated at 80 dB nHL, the response of the other ear at intensities down to 40 dB was not seriously affected; th e response at 20 dB nHL was, however, so diminished by contralateral s timulation at 80 dB that binaural testing would save no time. This met hod has promise for intraoperative monitoring and infant screening, an d could be used in threshold determination if the stimulus intensities for the two ears are not too dissimilar.