A recency effect in sound localization?
In a free-field pointing task, listeners localized trains of 4-32 spatially distributed Gabor clicks (narrowband impulses) centered at 4-kHz carrier frequency and repeating at an interval of 5 ms. Multiple regression coefficients estimated the perceptual "weight" applied to each click in a train during location judgments. Temporal weighting functions obtained in this way exhibited two key features: onset dominance, as evidenced by high weight on the initial click, and "upweighting" of late-arriving sound, as evidenced by weights that gradually increased over the duration of each click-train. Across all tested click-train durations, and despite randomly varying the durations from trial to trial, the greatest post-onset weights were consistently found for clicks at or near the offset. The results imply a special importance of late-arriving sound rather than feedforward recovery from onset dominance, and are broadly consistent with recency effects resulting from temporal integration.
Stecker
G Christopher
GC
Department of Speech and Hearing Sciences, University of Washington, Seattle, Washington 98105, USA. cstecker@u.washington.edu
Hafter
Ervin R
ER
D000161:Acoustic Stimulation; D000465:Algorithms; D006801:Humans; D016014:Linear Models; D009483:Neuropsychological Tests; D011571:Psychoacoustics; D013017:Sound Localization; D013647:Task Performance and Analysis; D013997:Time Factors