Tools for Bypassing Basic Language and Speech Deficits: A Survey of AAC and Assistive Communication Tools

Introduction

In this chapter, we turn from tools for boosting language skills in autism to tools designed primarily to bypass the language deficits—including speech deficits—that affect many individuals with severe autism. These tools fall into two general categories: tools for what is called “augmentative and alternative communication,” or AAC, and tools that provide communicative assistance. Generally speaking, AAC is any form of communication that supplements or substitutes for speech—from sign language to pictures to typing. Tools that provide communicative assistance, in contrast, facilitate communication in a given medium—typically typing. In our survey, we begin with tools for AAC.

In autism, the non-speaking or minimally-speaking individuals who most benefit from AAC are those who lack sufficient speech to meet daily communication needs—a subgroup that is estimated at 10-25% of the autistic population. Some do not speak at all; others can produce spoken words but not intelligibly enough for functional face-to-face communication (Mirenda, 2014).

Before we begin our survey of AAC programs and their utility to individuals with autism, it is useful to consider in greater depth the linguistic skills and needs of those for whom they are most appropriate.

While the most obvious linguistic challenge seen in those AAC users whose primary diagnosis is autism are their speech deficits, these deficits are typically accompanied by more fundamental language deficits, including deficits in vocabulary and comprehension. While some autism professionals have proposed that the speech deficits in autism are the result of an oral-motor impediment—namely, “apraxia of speech”—studies have failed to confirm apraxia as the main challenge in non-speaking autism (see Shriberg et al., 2011).

Shriberg et al. have proposed, rather, that the speaking difficulties of individuals with autism more likely result from a tendency not to tune in to the speech sounds made by other people—a tendency that is well attested in the autism literature—and a concomitant tendency not to practice approximating their own speech sounds to those of others. Also associated with non-speaking autism, Tager-Flusberg and Kasari (2013) propose, is an almost complete absence of social motivation. This is consistent with the various connections discussed in Chapter 3 between oral language skills and social behaviors like attending to social stimuli and responding to bids for joint attention, and with the fact that, without social motivation, there is little reason to tune in to speech.

Not tuning in to speech, in turn, limits one’s opportunities to learn, not just speech, but language in general. Except for sign language communities, speech is both the main form of language in the ambient environment and the main communicative medium of teachers and therapists. Some individuals with autism do tune in to visual signs and symbols, including letters— with various estimates indicating that somewhere between 6% and 21% exhibit hyperlexia, or a precocious ability to recognize printed words (Ostrolenk et al., 2017). Some of these hyperlexic individuals, including those who rarely tune in to speech sounds, may learn to associate certain letter patterns with certain objects or pictures.

These language learning opportunities, however, are limited to situations in which the written word is clearly linked to something that depicts its meaning. The most obvious instances of this kind of linkage occur in labeling—as seen, for example, in labels on food packaging. Words used to label, however, represent only a small fraction of written language. Nor do they provide a bootstrap into language as a whole. In particular, labels do not provide access to abstract nouns like “friendship,” or to most verbs, pronouns, and function words, or to the various verb tense forms and endings. For a child who has not learned the meaning of the spoken word “friendship” or the spoken verb ending “ing,” there is no way to figure out, on his own, the meaning of the written word “friendship” or the written ending “ing.”

What all this means is that the individuals for whom AAC tools are designed tend not just to have minimal speaking skills, but also minimal vocabularies, syntax skills, and overall language comprehension skills.

Fortunately, therefore, AAC tools do not just address speech issues, but also broader language issues. In particular, the picture/icon-based format that typifies most forms of AAC helps to bypass limitations in vocabulary. If the user does not know the meaning of the word “dog,” he may still be able to make sense of a visual depiction of a dog.