A study of auditory middle latency responses in relation to electrode combinations and stimulus conditions.
Auditory middle latency responses were recorded from healthy right-handed subjects. Acoustic clicks at a rate of 10/s were presented to the subjects via headphones. Using the electrode combination unilateral mastoid-nose tip, responses characterized by two early negative waves (about 11.5 and 18 ms peak latencies), followed by a late positive one (about 30 ms peak latency), were elicited by binaural stimulation (50-dB SL clicks). The waveform of responses from the unilateral mastoid-nose tip combination was similar to that recorded from a combination of the same side mastoid and a balanced noncephalic reference electrode, although the phase was opposite to that recorded from the Cz-unilateral mastoid combination. Auditory middle latency responses were recorded simultaneously from right mastoid and left mastoid and referenced to the nose tip; interaural differences in amplitude were found in most subjects. The amplitudes of the early components for binaural stimulation were larger than those for monaural stimulation.
D000161:Acoustic Stimulation / Q000295:instrumentation*; D000328:Adult; D001933:Brain Stem / Q000502:physiology*; D004566:Electrodes; D005072:Evoked Potentials, Auditory; D005260:Female; D006801:Humans; D008297:Male; D008416:Mastoid; D009666:Nose; D011930:Reaction Time