Monaural envelope correlation perception and broadband temporal analysis.

Abstract

Monaural envelope correlation perception [V. M. Richards, J. Acoust. Soc. Am. 82, 1621–1630 (1987)] is a paradigm that reflects sensitivity to the correlation between the temporal envelopes of carriers that are separated in frequency. Previous experiments investigating this paradigm have employed narrowband noise stimuli, presumably because of a desire to ensure that the temporal envelopes of the bands are faithfully represented at the outputs of frequency selective auditory filters. Although wide comodulated bands can be generated, a reasonable expectation is that the representations of the bands at the outputs of auditory filters corresponding to their center frequencies would have substantially reduced comodulation, partly due to the fact that the absolute width of the auditory filter increases with increasing stimulus frequency. Our preliminary data nevertheless indicate robust sensitivity to envelope correlation for noise bandwidths that greatly exceed the bandwidths of peripheral filters. This sensitivity persists even when manipulations are employed that should interfere with the ability to use spectral profile cues or cues based upon envelope comparisons across subsets of auditory filters. Results will be discussed in terms of cues supporting envelope correlation perception with stimuli that are broad with respect to auditory filters. [Work supported by NIDCD 5R01DC000418.]