Relationship between individuals' compensation for coarticulation and production

Abstract

This study examines the relationship between compensation for coarticulation and production. We tested individuals’ perceptual compensation of /s/ before /u/ and ability to imitate /s/ that were manipulated to sound equally over-coarticulated before /u/ and /a/. It is hypothesized that people who compensate more should converge less to the manipulated stimuli in the coarticulatory context. All /s/ were measured by center of gravity. Regression analyses showed that perceptual compensation is not a significant predictor of imitation of the manipulated /s/ in both contexts. We then obtained individuals’ perceptual and production /s/ distributions using the tasks and used an exemplar model which assigns different weights to the existing distributions and the stimuli to predict the production in imitation. The resulting stimuli weights are indicators of the degree of imitation. Again, the results showed no effect of perceptual compensation on the stimuli weight. Instead, it depends on the perceptual distributions: within a range, the perceptual distribution mean is positively correlated with stimuli weight, suggesting more imitation when the stimuli are perceptually saliently different from the existing distribution mean. These findings show that the perceptual-production relation can be better understood using a dynamic model that takes into consideration existing and new information.