Summary: Gradient Sensitivity to Within-Category Variation in Words and Syllables
Bob McMurray
University of Iowa
Richard N. Aslin and Michael K. Tanenhaus
University of Rochester
Michael J. Spivey
Cornell University
Dana Subik
University of Rochester
Five experiments monitored eye movements in phoneme and lexical identification tasks to examine the
effect of within-category subphonetic variation on the perception of stop consonants. Experiment 1
demonstrated gradient effects along voice-onset time (VOT) continua made from natural speech,
replicating results with synthetic speech (B. McMurray, M. K. Tanenhaus, & R. N. Aslin, 2002).
Experiments 2­ 5 used synthetic VOT continua to examine effects of response alternatives (2 vs. 4), task
(lexical vs. phoneme decision), and type of token (word vs. consonant­vowel). A gradient effect of VOT
in at least one half of the continuum was observed in all conditions. These results suggest that during
online spoken word recognition, lexical competitors are activated in proportion to their continuous
distance from a category boundary. This gradient processing may allow listeners to anticipate upcoming
acoustic­phonetic information in the speech signal and dynamically compensate for acoustic variability.
Keywords: speech perception, categorical perception, word recognition, subphonemic sensitivity, visual

Source: Aslin, Richard N. - Department of Brain and Cognitive Sciences, University of Rochester

Collections: Biology and Medicine