Abstract:

The categorization of voicing in syllable-initial stops is dependent primarily on voice onset time (VOT), while the categorization of place of articulation (POA) in stops is dependent primarily on higher formant transitions. This study tested for perceptual interactions among these two orthogonal acoustic dimensions (VOT and higher-formant transitions) and the corresponding phonological contrasts of voice and POA. Fifteen subjects categorized initial stops in a /Ca/ context as /ba/, /pa/, /ga/, or /ka/. The initial stop of each token was from a synthetic two-dimensional continuum with acoustic dimensions of VOT (0--45 ms) and second formant (F2) onset frequency (1100--1700 Hz), so that the corners of the continuum were unambiguous /ba/, /pa/, /ga/, and /ka/. A model of POA and voicing categorization derived from logistic regression suggests that the VOT category boundary can change depending on the perceived POA. Tokens categorized as bilabial were more likely than those perceived as velars to be also categorized as voiced, regardless of the F2 onset. The change in perceptual VOT boundary is consistent with previous results [J. R. Benki, J. Acoust. Soc. Am. 100, 2691 (1996)], though the magnitude of the effect is not as large. [Work supported by NSF.]