Autism Spectrum Disorder (ASD) Among Children Who Are Deaf

The issue

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For the past 50 years, some deaf children have been diagnosed with symptoms indicative of autism. As diagnostic criteria have been refined and awareness of symptoms has spread, increasing numbers of children are being diagnosed with autism spectrum disorder (ASD). In the general population, the Center for Disease Control or CDC in 2012 cited incidence statistics for ASD as 1 in 68 children. Unsurprisingly, then, increasing numbers of children who are deaf are being identified with symptoms indicative of ASD as well.

Autism Spectrum Disorder refers to developmental disabilities characterized by impairment in the ability to communicate and interact with others, with notable features including restricted or repetitive behaviors, interests, and activities. The term “spectrum” indicates that the expression of symptoms of autism vary widely in breadth and severity. ASD constitutes a range of serious neurodevelopmental disorders that can account for significant social, communication, and behavioral challenges.

What we know

The number of children diagnosed with ASD has increased dramatically in recent years, both in the general population and among children who are deaf or hard of hearing. This rise in incidence figures is attributable to factors including increased awareness, enhanced detection and reporting, plus a genuine increase in numbers of children appropriately diagnosed with ASD.

Every type of program designed for the education of deaf children is encountering students diagnosed with ASD. Technological advances have meant that many children born deaf now can access spoken language through the auditory modality. Some students, who through the use of digital hearing aids or cochlear implant devices are aural/oral communicators, exhibit issues with prosody and social exchange of communication that are uniquely characteristic of children with autism.

Deaf children with Deaf parents most typically have consistent access to language from infancy which accounts for the benefits usually demonstrated in their early language development and achievement. Yet, there are deaf children born to Deaf parents who fail to acquire language, sustain eye contact to receive and develop signed language, and exhibit stereotypic mannerisms and perseverative behaviors that are uniquely characteristic of children with autism.

Diagnosis of ASD among deaf children who exhibit neurobehavioral symptoms and patterns of development indicative of autism tends to be made later in childhood than among hearing children. Delays in language acquisition may be inaccurately attributed to their being deaf and having inadequate access to either signed or spoken language, without suspicion of behavioral presentations indicative of ASD.

Just as early identification and early intervention are keys to optimizing language, cognitive, and social development among infants and toddlers who are deaf or hard of hearing, early identification and early implementation of treatment for children with ASD can markedly improve developmental outcomes. The field as yet knows no “cure” for ASD. Intensive and appropriate intervention strategies implemented as early as possible can make a huge difference in the lives of children and for their families.

Numbers of professionals who are capable of offering differential diagnoses with young, deaf children are few and sparsely distributed – which brings us to huge question marks remaining in the field.

What we don’t know

What intervention strategies may prove most successful with deaf children who are diagnosed with ASD? Considerable work remains to determine these. While some children who are born deaf and receive cochlear implants at a young age respond favorably to having access to audition, others exhibit aversive reactions to sound and make no appreciable gains in aural/oral communication. Why, we do not yet know. Some deaf students with ASD acquire signed language and preferentially communicate through signing; others progress very little in language acquisition, despite rich access to visual/manual communication. Why, we do not yet know. Some deaf students with ASD learn to decipher written language and communicate preferentially through printed words. Yet, some never achieve literacy. Why, we do not yet know.

Where and how should deaf students with ASD be educated? Do such students fare better in programs targeted for children “on the spectrum”? In programs targeted for deaf and hard of hearing children? By incorporating services designed for students with ASD, yet implemented in the context of comprehensive programming for students who are deaf or hard of hearing? We do not yet know.

Implications

In grappling with increased incidence of ASD evident among deaf and hard of hearing students, implications for practice and treatment, policy decisions, honing diagnostic procedures, and providing parental supports all must be informed by evidence of effectiveness. The other bulletins in this posting provide several perspectives and explore multiple facets of this topic.

Posted on July 7, 2016 by
Terrell A. Clark
Director, Deaf and Hard of Hearing Program
Boston Children’s Hospital
Terrell.Clark {at} childrens.harvard.edu