A previous study by [J. Lee, G. Long, and C. Jeung, J. Acoust. Soc. Am. 119, S3332 (2006)] found that information at the onset or offset of modulation could be utilized for improved amplitude modulation (AM) depth discrimination in a continuous carrier condition (carrier presented 250 ms earlier and later than the modulator). In this study, the relative contribution of information at the onset or offset of the modulation was examined with an onset-fringe carrier condition (carrier begins 250 ms earlier than the modulator) and an offset-fringe condition (carrier ends 250 ms later than the modulator). The results suggest that modulation information at the onset might be utilized more than at the offset.