The autistic way of laughing

There are real and fake smiles that can be distinguished visually, if you know how, and it turns out that there are real and fake laughs.William Hudenko, a clinician and researcher, patiently explained this to me atIMFAR 2009. Real laughs are " voiced " versus fake laughs that are " unvoiced " and these two kinds of laughs can be distinguished acoustically.Hudenko et al. (in press) describe voiced laughs as having a " tonal, song-like quality " and as " strongly associated with positive affect, " while unvoiced laughs are " largely atonal and noisier. " Instead of reflecting a person ' s genuine emotions, unvoiced laughs are hypothesized to reflect various social signals.When nonautistics laugh, about half the time their laughs are unvoiced. So how do autistics laugh?Hudenko and his colleagues collected a lot of laughs from autistic children and two groups of nonautistic children (matched on chronological age, and matched according to vocabulary test age equivalents). Laughs were elicited in a 10-minute " laugh assessment sequence " in which " an examiner playfully interacted with each child. "The results? Autistics laughed just as much as nonautistics. The sole difference between autistic and nonautistic laughs was in proportion of voiced laughs. While on average, 97% of autistic children ' s " laugh episodes " were voiced, only 63% and 47% (age-equivalent and chronological age groups respectively) of nonautistic children ' s laughs were voiced. And about half the autistic c...
Source: The Autism Crisis - Category: Child Development Source Type: blogs