One of the strangest aspects of nonverbal autism is the fact that no one really knows why some people with autism can't - or don't - use spoken language. True, some people with autism also have childhood apraxia of speech, a neurological disorder that makes spoken language extremely difficult. But many nonverbal individuals on the autism spectrum don't have apraxia -- they just don't speak. Clearly, there are differences in brain function that inhibit spoken language, but at this point there is no agreement on just what those differences are or how they impact any given individual.
According to an NIH Workshop publication on Non-verbal School Aged Children with Autism, "...it is a very significant challenge to assess these individuals with traditional standardized instruments. Our current measurement tools have relatively low reliability and validity for this population. The presence of even one word, or some echolalic speech, appears to be a significant predictor for the acquisition of spoken language after five years of age. In both research and treatment planning, it is important to distinguish whether children are nonverbal (i.e., no spoken language), preverbal (i.e., younger children who have not yet developed verbal language), or non-communicative (i.e., having neither verbal nor nonverbal communication skills)."
There are many techniques for encouraging and improving spoken language for children with autism, though there is no guarantee that any particular approach will be effective for any given child. Research suggests that speech therapy, behavioral interventions, and even play therapy can improve verbal communication. Some early research also suggests that music therapy and related techniques can make a positive impact on speech.
Parents of children who don't yet have the ability to communicate effectively with spoken language should be aware of the following important - and often surprising - facts:
- Late language acquisition is not necessarily an indication of low IQ or poor prognosis.
- Children with autism may develop language much later than typically developing children, which means that it is worthwhile to continue speech therapy.
- Communication using non-verbal techniques (PECS picture cards, sign language, etc.) can be very important in establishing communication. Children who build communication skills using these techniques often gain spoken language skills at the same time.
- "Facilitated Communication," in which a therapist "supports" the arm of an autistic person while he or she types, has been debunked by numerous studies that show that it is the therapist, and not the autistic person, who is guiding the typing finger.
TL Layton. Language training with autistic children using four different modes of presentation. J Commun Disord. 1988 Aug;21(4):333-50.
National Institute on Deafness and Other Communication Disorders. Autism and Communication. NIH Pub. No. 09-4315, Updated July 2009.
National Institute on Deafness and Other Communication Disorders. NIH Workshop on Nonverbal School-Aged Children with Autism. April, 2010.
E Pickett et al. Speech acquisition in older nonverbal individuals with autism: a review of features, methods, and prognosis. Cogn Behav Neurol. 2009 Mar;22(1):1-21.
C Y Wan et al. From music making to speaking: Engaging the mirror neuron system in autism. Brain Res Bull. 2010 Apr 28.