Facilitation of the N1 peak of the auditory ERP at short stimulus intervals.

Event-related potentials (ERP) were recorded to 1 kHz tones presented at random stimulus onset asynchronies (SOA) between 100 and 1000 ms. The Adjar correction procedure was employed to overcome waveform distortion resulting from previous response overlap. The results showed dramatic enhancements of the N1 peak when SOA was reduced to 100-300 ms, showing a reversal of the traditional amplitude by SOA function obtained by previous ERP research employing SOAs > 500 ms, and replicating similar enhancements of the magnetic counterpart of the N1 (N100m). The results are discussed in terms of the utility of the traditional 'refractoriness' account of the sensitivity of the N1 to SOA.