Rhythmic Entrainment in Bilingual Speakers With Dysarthria

The objectives of this study are to determine i) the effect of rhythmic entrainment of speech
with hand gestures and auditory rhythmic cues on intelligibility and speech naturalness in
Spanish-accented speakers of English in two pathology groups: ataxic dysarthria and
hypokinetic dysarthria secondary to idiopathic Parkinson's disease; and ii) the extent to
which speech rate and effort are control parameters of entrainment. These objectives will be
achieved with the following specific aims:

Specific Aim 1: Determine the effect of three rates of hand gestures and auditory rhythmic
cues and the degree to which learning and carry-over occur.

Specific Aim 2: Determine the effect of increased speech effort, operationalized as clear
speech, and the interaction effect of clear speech with hand gestures and auditory rhythmic
cues.

Specific Aim 3: Investigate the perception of speech rhythm and its relationship to
entrainment.

The protocol calls for 12 talkers to participate in a single case experimental design: 6
Spanish-accented speakers of English and 6 native English speakers, and each language group
consisting of 2 healthy controls, 2 adults diagnosed with ataxic dysarthria and 2 adults
diagnosed with hypokinetic dysarthria secondary to idiopathic Parkinson's disease. Sixty
monolingual healthy adult listeners will rate intelligibility, accentedness, and ease of
understanding.

Inclusion Criteria:

- diagnosis of idiopathic Parkinson's disease (4) or dysarthria secondary to ataxia (4)
or healthy (4)

- monolingual speaker of American English (6) or native speaker of Spanish who speaks
English with a Spanish accent (6)

- age 21 or older

Exclusion Criteria:

- Cognitive impairment that prevents participation in the therapy

- Fluent speakers of languages other than English or Spanish

- younger than 21 years