Identification of Stress Placement in Speakers with and without Dysarthria Pamela Campellone Thomas DiCicco Rupal Patel

Background Traditional research focus in dysarthria due to CP: Articulation More recent research: Prosody Acoustic findings: Preserved prosodic control at vowel & word level

Background Are acoustic signals consistent and reliable? Can humans and/or machines make use of these signals? If prosody is a strength, can it be harnessed to improve segmental clarity?

Research Questions Can listeners identify stress within phrases produced by speakers with dysarthria & age-gender matched healthy controls? How accurate is machine classification of prosodic contrasts?

Method Spoken database: 12 speakers with dysarthria (DYS) & 12 healthy controls (HC) 5 phrases (4 monosyllabic words) produced with stress on 1 of the 4 words or neutrally 48 monolingual speakers of American English served as listeners 4 listeners per DYS-HC speaker pair

Listener Interface

Acoustic Predictors of Listener Accuracy (p<0.01)

Machine Classification HC & DYS words classified as stressed vs. unstressed HC accuracy: 98.1% DYS accuracy: 97.4% Separate combinations of duration, intensity, & F0 used to determine which were most predictive

Accuracy by Acoustic Predictors PredictorHCDYS Dur Int F Dur + Int Dur + F Int + F Dur + Int + F

Conclusions Unfamiliar listeners & machine classifier both highly accurate Communicative potential of prosody Clinically: scaffolding for improved intelligibility Application: communication aids which utilize prosodic variation

Future Directions Examine productions of speakers with varying etiologies of DYS Differences in acquired vs. congenital? Assess prosodic control in more varied speech tasks Design comprehensive interventions incorporating speaker and listener variables