title: An objective measurement of the build-up of auditory streaming and of its modulation by attention.
abstract: Three experiments studied auditory streaming using sequences of alternating "ABA" triplets, where "A" and "B" were 50-ms tones differing in frequency by Δf semitones and separated by 75-ms gaps. Experiment 1 showed that detection of a short increase in the gap between a B tone and the preceding A tone, imposed on one ABA triplet, was better when the delay occurred early versus late in the sequence, and for Δf = 4 vs. Δf = 8. The results of this experiment were consistent with those of a subjective streaming judgment task. Experiment 2 showed that the detection of a delay 12.5 s into a 13.5-s sequence could be improved by requiring participants to perform a task on competing stimuli presented to the other ear for the first 10 s of that sequence. Hence, adding an additional task demand could improve performance via its effect on the perceptual organization of a sound sequence. The results demonstrate that attention affects streaming in an objective task and that the effects of build-up are not completely under voluntary control. In particular, even though build-up can impair performance in an objective task, participants are unable to prevent this from happening.
authors.affiliation: MRC Cognition & Brain Sciences Unit, Cambridge, England.
authors.forename: Sarah K
authors.initials: SK
authors.lastname: Thompson
authors.forename: Robert P
authors.initials: RP
authors.lastname: Carlyon
authors.forename: Rhodri
authors.initials: R
authors.lastname: Cusack
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology*; D001307:Auditory Perception / Q000502:physiology*; D001309:Auditory Threshold; D004056:Differential Threshold; D004192:Discrimination, Psychological / Q000502:physiology*; D005260:Female; D005364:Field Dependence-Independence; D006801:Humans; D008297:Male; D008875:Middle Aged; D046709:Pattern Recognition, Physiological / Q000502:physiology*; D010470:Perceptual Masking / Q000502:physiology*; D012016:Reference Values; D013997:Time Factors; D055815:Young Adult