Computational Prosodic Markers for Autism
By Van Santen, Jan P.H.; Prud'hommeaux, Emily T.; Black, Lois M.; Mitchell, Margaret; Autism, OnlineFirstPublication Date: May 18, 2010
Article describes computer technology-based instrumental methods to explore differences in expressive prosody between children with autism spectrum disorder (ASD) and children with typical development (TD). These methods target dynamic patterns of acoustic features and are fully automatic, in contrast to traditional methods that capture only global features such as average pitch or pitch range and also require manual labor. Using these methods, three tasks were investigated: (1) the Lexical Stress task, a vocal imitation task where the computer plays a recording of a two-syllable nonsense word and the child repeats it with the same stress pattern; (2) the Emphatic Stress task, an imitation task where the child repeats an utterance in which one word is emphasized; and (3) the Focus task, wherein a recorded voice incorrectly describes a picture, for which the child must correct the voice by putting contrastive stress on the incorrect word. Participants were children with ASD and children with TD aged 4 to 8 years. The instrumental methods differentiated significantly between the ASD and TD groups in all but the Emphatic Stress task. The methods also showed smaller differences in the two vocal imitation tasks than in the picture description task. In the Lexical Stress task, the instrumental methods showed better performance for the ASD group. The methods also revealed that the acoustic features that predict auditory-perceptual judgment are not the same as those that differentiate between groups. A key difference between the groups appeared to be in the balance between the various prosodic cues, such as pitch, amplitude, and duration, rather than the strength or clarity with which prosodic contrasts are expressed.
Published by: Sage Publications (Website:http://www.sagepub.com)
Link to text: http://aut.sagepub.com/content/early/2010/05/14/1362361310363281.abstract
