Nonverbal autism refers to a presentation of Autism Spectrum Disorder where an individual has minimal or no functional spoken language. Communication challenges often lead to increased frustration and barriers to social engagement. Sign language is a practical and effective alternative communication tool for many individuals on the autism spectrum, providing a reliable means of expression and understanding.
Feasibility and Mechanisms of Sign Language Acquisition
Nonverbal individuals with autism can successfully acquire sign language because the modality aligns well with their cognitive strengths. Many autistic individuals demonstrate a preference for visual processing, making the visual-gestural nature of signing highly receptive. Unlike the rapid, transient nature of spoken words, a sign is a concrete visual symbol that remains present for better processing.
The physical movements of signing provide a tactile and kinetic element to communication, bridging the gap between a concept and its expression. Research shows that nearly all nonspeaking autistic children can learn receptive signs and often develop expressive skills, including combining signs into simple phrases. Sign language also reduces the high demand placed on auditory processing, which is often a difficulty for individuals on the spectrum.
The motor imitation skills necessary for signing are often more accessible than the complex motor planning required for vocal speech production. Mimicking a hand shape or movement translates directly into acquiring a functional vocabulary. By capitalizing on visual learning and motor strengths, sign language provides a direct pathway for communication that bypasses the auditory-vocal system challenges.
Specific Teaching Strategies for Sign Language
Instruction for teaching sign language is most effective when integrated into daily routines and focused on functional communication. The process begins by identifying highly motivating items or activities the individual desires, such as “eat,” “more,” or “all done.” These signs provide immediate and meaningful reinforcement for communication attempts.
Therapists and caregivers use simultaneous communication, producing the sign while speaking the corresponding word aloud. This multimodal approach links the visual sign, the auditory word, and the context of the requested item or action. Prompting strategies, such as physically guiding the individual’s hands to form a sign, are systematically faded as the person becomes independent.
Learning is reinforced when the communication partner immediately honors the request after a correct sign is produced, establishing the sign as a powerful tool for self-advocacy. The use of visual aids, like flashcards or pictures displaying the sign, can further reinforce the learning process by providing a consistent visual reference. Consistency across all environments and communication partners is paramount for the successful and generalized acquisition of the skill.
Sign Language and Spoken Language Development
A common concern is that teaching sign language will discourage or impede spoken language development. However, the consensus among language specialists is that sign language often serves as a beneficial communication bridge. It provides a functional means of expression, which reduces the frustration and challenging behaviors stemming from an inability to communicate needs and wants.
By providing a successful communication method, sign language lowers the pressure associated with verbal speech attempts. The motor-gestural output of signing supports the neural pathways involved in language organization, potentially setting the stage for later verbal development. Studies suggest that using simultaneous communication, where sign and speech are paired, stimulates language progress in children who eventually acquire some verbal skills.
Even if an individual does not transition to spoken language, the acquired sign vocabulary remains a reliable and always-available communication system. It allows for rich social interaction and the expression of complex ideas, which are fundamental to personal development and quality of life. Sign language should be viewed as a supportive tool that complements, rather than competes with, verbal speech development.
Sign Language Compared to Other Augmentative Communication Methods
Sign language is one form of Augmentative and Alternative Communication (AAC), encompassing all methods used to supplement or replace speech. Compared to other AAC tools, sign language offers the advantage of being an unaided system, requiring no external equipment and making it always accessible. Its limitations include requiring the communication partner to also know the signs and potential difficulty for individuals with fine motor impairments.
The Picture Exchange Communication System (PECS) is a low-tech, paper-based method where the individual hands a picture symbol to a partner to make a request. PECS is inexpensive and often used as an initial intervention for teaching the concept of communication. However, it requires carrying communication books or boards, which can be cumbersome, and it is slower for complex vocabulary development.
High-tech AAC devices, such as Speech-Generating Devices (SGDs) on tablets, offer extensive vocabulary and produce spoken output. These devices are robust and grow with the user’s language skills, providing a universally understood voice. The drawbacks include the high initial cost, the need for charging and maintenance, and a potential learning curve for navigation.
Ultimately, the choice of communication method is highly individualized, with sign language offering a powerful, readily available, and kinesthetic option.