Abstract:

Phonological speech errors are a traditional source of psycholinguistic evidence for the representations of phonology theory. In an electromyographic (EMG) study of experimentally induced phonological speech errors, Mowrey and MacKay [J. Acoust. Soc. Am. 88, 1299--1312] found that speech errors frequently occur at a subfeatural, gestural level, with no apparent effect on the percept of the word. Mowrey and MacKay's study considered the activity of a single muscle, and thus was unable to determine whether single gestures acted independently of gestural constellations. This study is a preliminary report from an ongoing acoustic analysis of speech errors. The data are tape recordings of an error-inducing experiment using nonsense tongue twisters. Recordings of six speakers producing four different tongue twisters targeting /s/ and /z/, e.g., sit zap zoo sip, were digitized and analyzed. Some errors involved multiple changes in acoustic properties, including simultaneous changes in periodicity, amplitude of frication, and duration, while others involved a subset of these properties. This evidence suggests that errors can occur at both the single gesture level, affecting noncontrastive acoustic properties, and at the level of the gestural complex or segment, creating a perceptible, linguistically contrastive change. [Work supported by NIH Grant No. DC00012.]