Perception of articulatory dynamics from acoustic signatures

Abstract

This study investigated the degree to which the articulatory trajectory of the tongue dorsum in the production of a vowel-vowel sequence is perceptually relevant. Previous research has shown that the tongue dorsum takes a path that leads to a pattern of area function change, termed the pivot pattern. In this study, articulatory synthesis was used to generate paths of tongue motion for the production of the vowel sequence /ai/. These paths differed in their curvature, leading to stimuli that conform to the pivot pattern and stimuli that violate it. Participants gave naturalness ratings and discriminated the stimuli. The acoustic properties were also compared to acoustic measurements made on productions of /ai/ by 34 speakers. The curvature of the tongue path and the curvature of the F1-F2 trajectory correlate highly with the naturalness-rating task results, but not the discrimination results. However, the particular way in which constriction location changes, particularly whether the change is discrete or continuous, and the maximal velocity of F2 through the transition, explain the perceptual patterns evident in both perception tasks, as well as the patterns in the observed acoustic data. Consequences of these results for the links between production and perception and the segmentation problem are discussed.

Hearing tongue loops: Perceptual sensitivity to acoustic signatures of articulatory dynamics

“…This is similar to the findings of Iskarous et al (2010) for vowel sequences (/ai/, in their case). It is interesting that there is still a similar amount of acoustic differentiation in loops of similar magnitude (say, numbers 1 and 7), yet their acceptability differs greatly (Fig.…”

“…In acoustic terms, strong CV transitions and weak VC transitions are preferred. It is not surprising, perhaps, that the most common pattern is preferred [though this was not the case for Iskarous et al (2010)], but it is surprising that this preference could be found in stimuli that all achieved their intended phonetic target ([aga]). Listeners appear to be extremely sensitive to the dynamical pattern of their language, picking up coarticulatory information as soon as it is available (e.g., Beddor et al, 2013).…”

“…Perception is often sensitive to the dynamics of speech production (e.g., Fowler, 2005;Iskarous, 2010;Liberman et al, 1967;Liberman and Whalen, 2000), but it is not always the case that what is typically produced is the preferred perceptual pattern: Recent work by Iskarous et al (2010) examined vowel sequences created with articulatory synthesis that had an articulatory "pivot point" (Iskarous, 2005), or a greater or lesser degree of approximation of the tongue to the palate. The pivot pattern is that most typically produced, and it was found to be preferred over trajectories in which the tongue glides upward along the palate.…”

Computational simulation of CV combination preferences in babbling

“…The minimal constriction locations did not always show gradual change but rather exhibited discrete shifts in constriction location (c.f. Iskarous, Nam, & Whalen, 2010). We estimated the constriction location boundaries by using the discrete constriction location boundaries where they occurred supplemented by the acoustic boundaries.…”

Variability in English vowels is comparable in articulation and acoustics

“…Strange, Jenkins and Johnson 1983). Iskarous, Nam and Whalen (2010) found listeners to be sensitive to the movement patterns of formants (presumably reflecting the underlying kinematics) even when the vowel categories were always correctly identified. Such results argue for a theory of vowel perception that is sensitive to a great deal of the structure throughout the syllable.…”