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.
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.