Working memory demands of aided augmentative and alternative communication for individuals with developmental disabilities

When speech is not functional to meet some or all of an individual's communication needs, aided augmentative and alternative communication (AAC) systems are often implemented. Although aided AAC systems offer some advantages over speech, they also impose some unique demands, especially on working memory, which is commonly defined as the cognitive system by which individuals maintain and manipulate information while completing tasks. For instance, the presence of an external aided AAC device containing arrays of symbols, not all of which are visible simultaneously, presents multiple working memory demands: individuals must maintain the target concepts in mind, all the while (a) navigating through multiple pages, (b) remembering the appropriate or most efficient navigation path, (c) locating the target symbols within the array once the host page has been located, and (d) inhibiting responses to potentially interesting distracters throughout the process. Each of these task demands involves one or more working memory operations that have been identified and studied extensively in research in the cognitive sciences. Failure to acknowledge or understand how working memory might interact with AAC use may place unintentional barriers to effective AAC interventions. This paper explores current information about working memory operations and highlights some of the most relevant issues that warrant further direct study.