Temporal weighting in loudness of broadband and narrowband signals

Temporal weights used by listeners when judging the overall loudness of a stimulus were measured for a 1-s-long noise centered around 2 kHz, whose level was randomly perturbed every 100 ms. The bandwidth was either 6400 Hz (broadband condition) or 400 Hz (narrowband condition). The first 100 ms contributed significantly more than later segments to overall loudness perception in the broadband condition. The effect was significantly reduced in the narrowband condition which is in line with the hypothesis that a greater spectral loudness summation at stimulus onset might be the mechanism behind the onset accentuation.