Fast binaural processing but sluggish masker representation reconfiguration

Perceptual organization of complex acoustic scenes requires fast binaural processing for accurate localization or lateralization based on short single-source-dominated glimpses. This sensitivity also manifests in the ability to detect rapid oscillating interaural time and phase differences as well as interaural correlation. However, binaural processing has also been termed “sluggish” based on experiments that require binaural detection in a masker with an additional binaural cue change in temporal proximity. The present study shows that the temporal integration windows obtained from data on binaural sluggishness cannot account for the detection of rapid binaural oscillations. A model with fast IPD encoding but a slower process of updating the internal representation of the masker IPD statistics accounted for both experiments of the “fast” and the “sluggish” categories.