http://www.sciencedaily.com/releases/2008/...80425144319.htm
"ScienceDaily (Apr. 26, 2008) — What began as an informal presentation by a clinical linguist to a group of philosophers, has led to some surprising discoveries about the communicative language abilities of people with autism.
Several years back, Robert Stainton, now a philosophy professor at The University of Western Ontario, attended a presentation by his long-time friend Jessica de Villiers, a clinical linguist now at the University of British Columbia. The topic was Autism Spectrum Disorder (ASD). De Villiers explained that many individuals with ASD have significant difficulties with what linguists call "pragmatics." That is, people with ASD often have difficulty using language appropriately in social situations. They do not make appropriate use of context or knowledge of what it would be "reasonable to say." Most glaringly, many speakers with ASD have immense trouble understanding metaphor, irony, sarcasm, and what might be intimated or presumed, but not stated.
Drawing on his philosophical training, however, Stainton noticed less-than-obvious pragmatic abilities at work in de Villiers' examples, which were drawn from transcripts of conversations with 42 speakers with ASD -- abilities that had been missed by clinicians. "