The role of linguistic variability in the perception of voice cues

Abstract

Talkers’ voices play an important role in speech perception. Through voices, we identify individual talkers and can facilitate speech communication in challenging conditions (e.g., cocktail party situations). While previous research has suggested that several linguistic factors broadly influence talker perception, how these factors influence perception of the individual voice cues remains unclear. The current study investigated the role of linguistic variability in voice cue perception, specifically fundamental frequency (F0) and vocal-tract length (VTL). Just-Noticeable-Differences (JNDs) were obtained using a 3AFC adaptive paradigm. Effects of word status (words, nonwords), word characteristics (lexical frequency, neighborhood density), and nonword characteristics (phonotactic probability, neighborhood density) were examined. Results demonstrated that voice cue perception was influenced by linguistic variability. While overall similar for words and nonwords, F0 and VTL JNDs were affected by phonological information in nonwords, i.e., phonotactic probability, but not on lexical information, i.e., lexical frequency and neighborhood density. However, VTL JNDs varied less across linguistic conditions than F0 JNDs, suggesting different processing mechanisms for these voice cues. These findings provide better insight into the interaction of voice and linguistic information, which may also improve our understanding of speech perception processes in populations with limitations in voice perception, such as cochlear-implant listeners.