In this talk, I will show how different groups of listeners use voice acoustics to enhance speech comprehension under adverse listening conditions, specifically when the auditory scene comprises a multitude of sounds heard at once. These "cocktail-party"-like situations pose a difficult conceptual problem for normal-hearing listeners and are particularly challenging for cochlear-implant users: To comprehend target speech, listeners need to attend to the target voice while at the same time ignoring other irrelevant sounds.

The cocktail-party problem is made considerably easier when all target sounds are spoken by the same talker. Previous work suggests that this so-called voice-continuity benefit can be—in large part—attributed to continuity in two prominent voice features: Glottal-pulse rate (GPR) and vocal-tract length (VTL). GPR determines the fundamental frequency of a speech sound and is perceived as vocal pitch; VTL determines the spectral envelope of a speech sound and is perceived as an aspect of vocal timbre. Apart from being important voice identity cues, GPR and VTL have been shown to contribute to both stream segregation and perceptual grouping in cocktail-party listening.

Here, I will present data from a series of experiments highlighting similarities and differences in how normal-hearing listeners and cochlear-implant users exploit continuity in GPR and VTL to group sounds at the cocktail party.