LAUSR

Slow, loud, and clear speech can elicit increased acoustic vowel contrast in talkers with dysarthria. However, articulator-specific changes in response to these speech modifications and their relative contribution to vowel acoustic changes remain poorly understood despite the fact that these three speech modulations are commonly used as speech treatments to increase intelligibility in dysarthria. This preliminary study examined tongue and jaw movements in talkers with Parkinson’s disease (PD) and amyotrophic lateral sclerosis (ALS) using electromagnetic articulography. Participants repeated the phrase “See a kite again” five times under four speech conditions: typical, slow, loud, and clear speech. Tongue movements were decoupled from the jaw to determine the relative contribution of the jaw and tongue to the overall tongue composite movement during the diphthong /ai/ in “kite”. In the acoustic signal, the F2 minimum during /a/ and the F2 maximum during /i/ and their corresponding F1 values were extracted...