Perspectives on Speech and Language Interaction for Daily Assistive Technology

This special issue of TACCESS focuses on the use of speech and language processing in assistive technology as a way of improving the daily life of people with disabilities.The International Classification of Functioning, Disability and Health (ICF) [World Health Organization 2001] defines disability as “an umbrella term for impairments, activity limitations, and participation restrictions.” An impairment is a problem in body function or structure, an activity limitation is a difficulty encountered by an individual in executing a task or action (such as in the case of cerebral palsy or Alzheimer’s disease), while a participation restriction is a barrier experienced by an individual engaged in life situations (such as inaccessible transportation and public buildings, and limited social supports). It is clear that disability is not only a personal health problem but a complex phenomenon related to the interaction between aspects of individuals and the society in which they live. Hence, overcoming the difficulties faced by people with disabilities requires interventions to break down environmental and social barriers. In the last two decades, there has been a growth in the development and application of technology (widely known as assistive technologies) to improve the lives of people with disabilities. Assistive technology (AT) “[refers] to a broad range of devices, services, strategies and practices that are conceived and applied to ameliorate the problems faced by individuals who have disabilities” [Cook and Polgar 2008]. According to ISO 9999:2007, “Assistive products for persons with disability – Classification and terminology,” an AT product (including devices, equipment, instruments, technology and software) is “specially produced or generally available, for preventing, compensating for, monitoring, relieving or neutralizing impairments, activity limitations and participation restrictions.” This definition stresses that AT is designed for individuals with disabilities to enable them to do things that would otherwise be difficult or impossible. This mirrors a shift seen in recent years from focusing on the disability in general to focusing on the individual and basing each AT development on a user-centered design [Hawley 2013]. It follows that an important measure of success of an AT should be concentrated around the actual increase of functional capability – to what extend has a particular AT helped an individual overcome a barrier that individual was facing in daily life? This in turn necessitates that good AT design must not only improve functional capability, but also must be accompanied by appropriate evaluation methods. Proper evaluation can validate and predict actual impact and suitability to personal requirements. Research in AT has subsequently pursued two main targets: ways of compensating for a functional loss (e.g., speech-generating devices for people with speech impairment) and making the environment more accessible (e.g., signs translated in Braille for people who are blind). In Information and Communications Technology (ICT), which is the scientific domain of this special issue, ISO 9999:2007 defines assistive products for communication and information as devices for helping people receive, send, produce, and/or process information in different forms. This includes devices for seeing, hearing, reading, writing, telephoning, signalling, and emergency response. Speech and natural language processing (NLP) can thus play an important role in a variety of ways, including improving the intelligibility of unintelligible speech, providing communicative assistance for people with some communication disorders, and providing speech interfaces that