The temporal weighting of loudness: effects of the level profile.
In four experiments, we studied the influence of the level profile of time-varying sounds on temporal perceptual weights for loudness. The sounds consisted of contiguous wideband noise segments on which independent random-level perturbations were imposed. Experiment 1 showed that in sounds with a flat level profile, the first segment receives the highest weight (primacy effect). If, however, a gradual increase in level (fade-in) was imposed on the first few segments, the temporal weights showed a delayed primacy effect: The first unattenuated segment received the highest weight, while the fade-in segments were virtually ignored. This pattern argues against a capture of attention to the onset as the origin of the primacy effect. Experiment 2 demonstrated that listeners adjust their temporal weights to the level profile on a trial-by-trial basis. Experiment 3 ruled out potentially inferior intensity resolution at lower levels as the cause of the delayed primacy effect. Experiment 4 showed that the weighting patterns cannot be explained by perceptual segmentation of the sounds into a variable and a stable part. The results are interpreted in terms of memory and attention processes. We demonstrate that the prediction of loudness can be improved significantly by allowing for nonuniform temporal weights.
Department of Psychology, Johannes Gutenberg-Universität Mainz, Mainz, Germany. oberfeld@uni-mainz.de
Daniel
D
Oberfeld
Tina
T
Plank
D000161:Acoustic Stimulation / Q000379:methods; D000328:Adult; D001288:Attention; D004192:Discrimination, Psychological; D005260:Female; D006801:Humans; D007600:Judgment; D008144:Loudness Perception; D008297:Male; D011571:Psychoacoustics; D013018:Sound Spectrography; D013998:Time Perception; D055815:Young Adult