Augmentative and alternative communication

Augmentative and alternative communication is used by individuals to compensate for severe speech-language impairments in the expression or comprehension of spoken or written language. People making use of AAC include individuals with a variety of congenital conditions such as cerebral palsy, autism, intellectual disability, and acquired conditions such as amyotrophic lateral sclerosis, traumatic brain injury and aphasia. An estimated 0.05% of children and young people require high technology AAC. The bulky dedicated devices of the 1970s have evolved immensely while growing the ACC app industry. However, the continued high rates of limited use and abandonment highlight the need for a shift in design, while focusing on minimizing cognitive load and adapting to each user's unique language needs a long with their physical needs as well. Well-known AAC users include physicist Stephen Hawking, broadcaster Roger Ebert and poet Christopher Nolan. Award-winning films such as My Left Foot and The Diving Bell and the Butterfly, based on books by AAC users Christy Brown and Jean-Dominique Bauby respectively, have brought the lives of those who use AAC to a wider audience. ==Forms of AAC==

Unaided AAC Unaided AAC systems are those that do not require an external tool, and include facial expression, vocalizations, gestures, and sign languages and systems. Informal vocalizations and gestures such as body language and facial expressions are part of natural communication, and such signals may be used by those with profound disabilities. More formalized gestural codes exist that lack a base in a naturally occurring language. For example, the Amer-Ind code is based on Plains Indian Sign Language, and has been used with children with severe-profound disabilities, and adults with a variety of diagnoses including dementia, aphasia and dysarthria. The benefits of gestures and pantomime are that they are always available to the user, usually understood by an educated listener, and are efficient means of communicating. In contrast, sign languages have a linguistic base and permit the expression of an unlimited number of messages. In the United States of America, Signing Exact English may be considered the most widely used example of the former and American Sign Language as a common example of the latter. The specific hand shapes and movements of sign and gesture require an individual to have adequate fine motor and motor planning skills. Sign languages require more fine-motor coordination and are less transparent in meaning than gestural codes such as Amer-Ind; the latter limits the number of people able to understand the person's communication without training. Low-tech Low-tech communication aids are defined as those that do not need batteries, electricity or electronics. These are often very simple communication boards or books, from which the user selects letters, words, phrases, pictures, and/or symbols to communicate a message. Depending on physical abilities and limitations, users may indicate the appropriate message with a body part, light pointer, eye-gaze direction, or a head/mouth stick. Alternatively, they may indicate yes or no while a listener scans through possible options. Picture Communication Exchange System (PECS) is a commonly used low-tech communication system that teach individuals how to request, comment, and answer questions. High-tech High-tech AAC aids permit the storage and retrieval of electronic messages, with most allowing the user to communicate using speech output. Such devices are known as speech generating devices (SGD) or voice output communication aids (VOCA). A device's speech output may be digitized and/or synthesized: digitized systems play recorded words or phrases and are generally more intelligible while synthesized speech uses text-to-speech software that can be harder to understand but that permits the user to spell words and speak novel messages. High-tech systems may be dedicated devices developed solely for AAC, or non-dedicated devices that run additional software to function as AAC devices. These options are typically more affordable than a dedicated device. Examples of AAC applications that function on non-dedicated hardware include Avaz and Spoken. The freedom to use existing, personal devices like smartphones for AAC has resulted in more users. High-tech AAC may be static or dynamic in form. Static communication devices have symbols in a fixed positions on paper overlays, which are changed manually. To increase the vocabulary available, some static devices have multiple levels, with different words appearing on different levels. On dynamic AAC devices, the user can change the symbols available using page links to navigate to appropriate pages of vocabulary and messages. High-tech devices vary in the amount of information that they can store, as well as their size, weight and thus their portability. Access methods depend on the abilities of the user, and may include the use of direct selection of symbols on the screen or keyboard with a body part, pointer, adapted computer mice or joysticks, or indirect selection using switches and scanning. Devices with voice output offer their user the advantage of more communicative power, including the ability to initiate conversation with communication partners who are at a distance. However, they typically require programming, ==Symbols==

At its most basic definition, a symbol is something that represents or stands for something else. Symbols represent objects, actions, and concepts through the use of items such as the physical object itself, colored or black and white photographs, line drawings, and written words. For users with literacy skills, alphabet-based symbols including individual letters, whole words, or parts thereof may be used in combination with the other types of symbols. Tactile symbols are textured objects, real objects or parts of real objects that are used as a communication symbols particularly for individuals with visual impairments and/or significant intellectual impairments. Both low- and high-tech devices can incorporate the use of symbols. Symbols are often placed in fixed positions on the screen or board which allow users to develop motor patterns associated with certain requests or statements. With low-tech devices, a communication partner is involved and must interpret the symbols chosen. The choice of symbols and aspects of their presentation, such as size and background, depend on an individual's preferences as well as their linguistic, visual, and cognitive skills. This can be determined using an assessment for symbolic understanding. Over time, several collections or symbol-sets have been developed by individuals, non-profit organizations, and companies: • AAC Image Library • ARASAAC • LessonPix • Mulberry • Picture Communication Symbols (PCS), which are currently owned and maintained by Tobii Dynavox • Sclera • Smarty Symbols • Symbolstix Prime • Tawasol Symbols • Twinkl Symbols • Widgit Symbol Set ==Access and selection methods==

Technological advances have dramatically increased the types of selection methods available for individuals with communication impairments. Direct activation of an AAC system is generally the first choice of access method as it is faster and cognitively easier. Those unable to do so may use indirect selection or "scanning". In this method, items displayed for selection are scanned; the scanning may be visual using indicators such as lights, highlighting, and/or contrasting borders, or auditory using spoken prompts from a communication partner or device. When the desired message is reached, the AAC user indicates the choice using an alternative selection technique such as a switch, vocalization or gesture. Several different patterns for switch access scanning are available: in "circular scanning", the items are displayed in a circle and then scanned one at a time. It is often the first type introduced to children or beginning AAC users because it is the easiest to understand. In "linear scanning", items are organized in rows and are scanned one at a time until a choice is made. Although more demanding than circular scanning, it is still easy to learn. Finally, in "group-item scanning", items are grouped and the groups scanned consecutively. Once a particular group is selected, items within the group are scanned. One of the most common group-item strategies is row-column scanning in which each row forms a group. The rows of items are scanned, and when a row is selected, the items in the row are scanned one at a time until a message is selected. There are three main selection control techniques in scanning. In "automatic scanning", the scan proceeds at a pre-determined speed and pattern until the user selects an item. In "inverse scanning", the switch is held down to advance the scan, and released to choose the desired item. In "step scanning", the AAC user activates one switch to move the indicator through the items, and another switch to select the item. ==Vocabulary organization==

Vocabulary organization refers to the way pictures, words, phrases, and sentences are displayed on the communication system. In general, the goal is to facilitate efficient and effective communication, especially when the individual's AAC system contains a large number of symbols. Communication books and devices are often presented in a grid format; the vocabulary items displayed within them may be organized by spoken word order, frequency of usage or category. In the Fitzgerald Key organization, symbols from different semantic and syntactic classes are organized grammatically in groups from left to right to facilitate sentence construction. Since research has shown that children and adults use a small number of words frequently, in a core-fringe vocabulary organization, the words and messages that are communicated most frequently appear on a "main page". The fringe vocabulary—words and messages used more rarely and that are specific to an individual—appear on other pages. Symbols may also be organized by category, grouping people, places, feelings, foods, drinks, and action words together. Each display contains symbols for the people, places, objects, feelings, actions, and other relevant vocabulary items for a specific activity or routine. Visual scene displays are a different method of organizing and presenting symbols. These are depictions of events, people, objects, and related actions in a picture, photograph, or virtual environment representing a situation, place, or specific experience. They are similar to activity displays in that they contain vocabulary that is associated with specific activities or routines. For example, a photo of a child's room may be included in the child's AAC system. Objects and events within the photograph are then used as symbols for communication. ==Rate enhancement strategies==

Augmentative and alternative communication is typically much slower than speech, with users generally producing 8–10 words per minute. Prediction is a rate enhancement strategy in which the device attempts to predict the letter, word or phrase being written by the user. The user can then select the correct prediction without needing to write the full word. Word prediction software may determine the words predicted based on their frequency in language, association with other words, past choices of the user, or grammatical suitability. ==Assessment and system implementation==

An evaluation of an individual's abilities, limitations and communication needs is necessary to select appropriate AAC techniques. The purpose of the assessment is to identify potential AAC approaches that can bridge discrepancies between a potential user's current communication and their present and future communication needs. AAC evaluations are often conducted by specialized teams which may include a speech-language pathologist, occupational therapist, rehabilitation engineer, physiotherapist, social worker and a physician. Users, family members and teachers are also key members of the decision making team. Sensitivity to and respect of cultural diversity contributes to ongoing family involvement and to the selection of the most appropriate AAC system. For members of some cultural groups the presence of an AAC device increases the visibility of disability and is thus viewed as stigmatizing. A user's motor abilities, communication skills and needs, cognition and vision are assessed in order to determine the most appropriate match to a communication system. In Western cultures, professionals may see a communication device as helping to promote an individual's self-determination, i.e., the ability to make one's own decisions and choices. However, cultural and religious factors may affect the degree to which individual autonomy is a valued construct, and influence family attitudes towards AAC. Skilled users of AAC show communicative competence in four interrelated areas: linguistic, operational, social and strategic. Linguistic competence refers to language skills in the person's native language as well as the linguistic code of the symbol system selected. Operational competence involves the skills in the use and maintenance of the tool of communication, while social competence and strategic competence reflect knowledge and judgment in communicative interactions, including the compensations required for a slow speaking rate, communication breakdowns and those unfamiliar with AAC. An AAC user may require specific device programming and/or training to achieve competency in these areas. Communication partners may also require training to notice and consistently interpret the communication signals of a severely disabled individual, particularly because there is a danger that learned helplessness can be the result of repeated failure to communicate successfully. Parties may need assistance to avoid the directive communication style that can lead a child user of AAC not to develop a full range of communication skills such as initiating or taking the lead in conversation, using complex syntax, asking questions, making commands or adding new information. Young AAC users benefit from rich language and literacy experiences to foster vocabulary development, discourse skills, and phonological awareness, all of which supports successful literacy learning. ==Outcomes==

Speech Several reviews have found that the use of AAC does not impede the development of speech in individuals with autism or developmental disabilities, and in fact, may result in modest gains being observed. A 2006 research review of 23 AAC intervention studies found gains in speech production in 89% of the cases studied, with the remainder showing no change. Researchers hypothesize that using an AAC device relieves the pressure of having to speak, allowing the individual to focus on communication, and that the reduction in psychological stress makes speech production easier. Others speculate that in the case of speech generating devices, the model of spoken output leads to an increase in speech production. Language and literacy Language and literacy have far reaching effects as they facilitate self-expression and social interaction in a variety of settings. Furthermore, literacy fosters independence by providing access to educational and vocational opportunities. Most children in this category do not achieve literacy skills beyond that of a typically developing 7–8 year old. Cognitive, language and learning delays contribute to difficulty with literacy development, but environmental factors also play a role. The most literate AAC users often report having access to abundant reading and writing material at home as well as in school during childhood. Studies have shown that many children who use AAC have literacy experiences that are reduced quality, quantity, and opportunity at home and at school as compared to children without disabilities. Research suggests that with explicit reading instruction, AAC users can develop good literacy skills. Factors that have been found to be related to employment are a strong work ethic and access to AAC technology, the support of family and friends, education, and work skills. Individuals with ALS who use AAC may continue working; factors supporting continued employment include access to AAC, support from employers, governmental programs and others. Employers of AAC users report that skills in time management, problem solving, communication, technology and a good education are important to employers. Quality of life Several studies of young adults who had used AAC since childhood report a generally good quality of life, though few lived independently, or were in paid employment. More positive quality of life outcomes often correlated with better quality of communication and interaction, as well as personal characteristics, family and community support, and excellent AAC services. Poorer outcomes were related to lack of access to appropriate AAC supports and resources, problems with technology and negative attitudes. ==Specific groups of AAC users==

Cerebral palsy Cerebral palsy is a term referring to a non-progressive developmental neuromotor disorder with an upper motor neuron lesion origin. Depending on the location of the brain lesion, individuals with cerebral palsy can have a wide variety of gross and fine motor challenges, including different forms and areas of the body affected. Fine motor planning, control and coordination are often affected. Dysarthria, a speech disorder resulting from neurological damage to the motor-speech system, occurs in an estimated 31% to 88% of those with cerebral palsy. Such individuals may require AAC support for communication. Approximately one half to one third have some degree of intellectual impairment, and visual and hearing problems are also common. Gross and fine motor challenges are often of particular concern in accessing an AAC device. Extensive motor training and practice may be required to develop efficient AAC access and use. The trend towards custom-placed sensors and personalized signal processing may assist in facilitating communication for those who are incapable of using other AAC technologies. Intellectual impairment Individuals with intellectual impairments face challenges in developing communication skills, including problems with generalization (the transfer of learned skills into daily activities). They may lack communication opportunities in their daily lives, and responsive communicators who understand their communication methods. increase participation in activities, and even influence the perceptions and stereotypes of communication partners. Although most individuals with intellectual disabilities do not have concomitant behavioural issues, problems in this area are typically more prevalent in this population than others. AAC approaches may be used as part of teaching functional communication skills to non-speaking individuals as an alternative to "acting out" for the purpose of exerting independence, taking control, or informing preferences. Autism Autism is a disorder of neural development characterized by impaired social interaction and communication, and by restricted and repetitive behaviour. Typically there is particular difficulty acquiring expressive communication skills. Autistic people have been found to have strong visual processing skills, making them good candidates for an AAC approach. AAC intervention in this population is directed towards the linguistic and social abilities of the child, including providing the person with a concrete means of communication, as well as facilitating the development of interactional skills. AAC systems for this population generally begin with communication boards and/or object or picture exchanges such as the Picture Exchange Communication System (PECS). Developmental verbal dyspraxia Developmental verbal dyspraxia, also known as childhood apraxia of speech, is a developmental motor speech disorder involving impairments in the motor control of speech production. The speech of a child with developmental verbal dyspraxia may be unintelligible to the point that daily communication needs cannot be met. A child with developmental verbal dyspraxia often experiences great amounts of frustration, so AAC can be a strategy to support communication alongside more traditional speech therapy to improve speech production. A wide variety of AAC systems have been used with children with developmental verbal dyspraxia. Manual signs or gestures are frequently introduced to these children, and can include the use of fingerspelling alongside speech. Manual signs have been shown to decrease errors in articulation. Depending on the stage of recovery, AAC intervention may involve identifying consistent communication signals, the facilitation of reliable yes/no responses to questions, and the ability to express basic needs and answer questions. Individuals who do not recover natural speech to a degree sufficient to meet their communication needs typically have severe impairments related to cognition. Difficulties with memory and learning new skills may influence AAC choices; well-established competencies such as spelling may be more effective than AAC systems that require navigation through multiple pages to access information. Individuals with aphasia often communicate using a combination of speech, gestures, and aided communication; the proportion of each may change as the person recovers, and depends on the context and the individual's skills. Depending on their language and cognitive skills, those with aphasia may use AAC interventions such as communication and memory books, drawing, photography, written words, speech generating devices and keyboards. Communication boards can be very helpful for patients with aphasia, especially with patients who are very severe. They can be produced at a very low tech level, and can be utilized by patients to point to pictures/words they are trying to say. Communication boards are extremely functional and help patients with aphasia communicate their needs. Locked-in syndrome Strokes that occur in the brainstem may cause profound deficits, including locked-in syndrome, in which cognitive, emotional and linguistic abilities remain intact but all or almost all voluntary motor abilities are lost. Most people affected by this type of stroke rely on AAC strategies to communicate, since few recover intelligible speech or functional voice. The AAC strategies used vary with the individual's preferences and motor capabilities which may change over time. As eye movements are most likely to be preserved, eye blinks are frequently used for communication. In a procedure known as voice banking, people with ALS may digitally record words and phrases while still able to do so, for later inclusion in a communication device. AAC systems used typically change over time depending on severity of speech impairment, physical status, and the individual's communication needs. Use of augmentative communication strategies generally begins when speaking rate drops to 100 words per minute. In the early stages, AAC may consist of using an alphabet board to cue the listener to the first letter of the word being spoken, and may be used with those less familiar with the individual. In the later stages, AAC often becomes the main communicative method, although familiar conversation partners may still understand some spoken words. Since cognition and vision are typically unaffected in ALS, writing-based systems are preferred to graphic symbols, as they allow the unlimited expression of all words in a language. In the bulbar form, speech is affected before the limbs; here handwriting and typing on keyboard-style devices are frequently the first forms of AAC. Parkinson's disease Parkinson's disease is a progressive neurological condition in which dysarthria may develop later in the progression of the disease. Some individuals eventually lose all functional speech. AAC approaches are generally used to supplement and support natural speech. Multiple sclerosis Dysarthria is the most common communication problem in individuals with multiple sclerosis (MS), however, significant difficulties with speech and intelligibility are uncommon. Individuals with MS vary widely in their motor control capacity and the presence of intention tremor, and methods of access to AAC technology are adapted accordingly. Visual impairments are common in MS and may necessitate approaches using auditory scanning systems, large-print text, or synthetic speech feedback that plays back words and letters as they are typed. Dementia Dementia is an acquired, chronic, cognitive impairment characterized by deficits in memory and other cognitive domains. Communication impairments are partly attributed to memory deficits, Low-tech devices are generally preferred, such as memory books that include autobiographical information, daily schedules, photographs, and reminders or labels. The gains were maintained four months after the training in the use of the memory aids had ceased. Temporary users are unlikely to invest in dedicated hardware due to the short-term nature of their needs. Instead, they often opt for low-tech options like communication boards or more cost-effective high-tech options like mobile apps. ==History==

The history of AAC can be traced to the days of classical Rome and Greece, with the first recorded use of augmentative strategies with the deaf. The use of manual alphabets and signs was recorded in Europe from the 16th century, as was the gestural system of Hand Talk used by Native Americans to facilitate communication between different linguistic groups. The modern era of AAC began in the 1950s in Europe and North America, spurred by several societal changes; these included an increased awareness of individuals with communication and other disabilities, and a growing commitment, often backed by government legislation and funding, to develop their education, independence and rights. In the early years, AAC was primarily used with laryngectomy and glossectomy cases, and later with individuals with cerebral palsy and aphasia. It was typically only employed after traditional speech therapy had failed, as many felt hesitant to provide non-speech intervention to those who might be able to learn to speak. The use of Amer-Ind hand signals opened the field to AAC techniques specifically for adult users. At the same time, AAC users and family members played an increasing prominent role in the development of knowledge of AAC through their writing and presentations, by serving on committees and founding advocacy organizations. Rapid progress in hardware and software development continued, including projects funded by the European Community. The first commercially available dynamic screen speech generating devices were developed in the 1990s. At the same time synthesized speech was becoming available in more languages. Software programs were developed that allowed the computer-based production of communication boards. On July 25, 2024, Jennifer Wexton became the first member of the House of Representatives to have a model of her voice generated by artificial intelligence speak for her on the House floor, which made her the first member of the House of Representatives to use any AAC device on the House floor. The model said in part, “My battle with progressive Supranuclear palsy, or PSP, has robbed me of my ability to use my full voice and move around in the ways that I used to”. Future directions for AAC focus on improving device interfaces, reducing the cognitive and linguistic demands of AAC, and the barriers to effective social interaction. which can generate astonishing results; however, the user interfaces are needed that meet the various physical and cognitive challenges of AAC users. Android and other open source operating systems, provide opportunities for small communities, such as AAC, to develop the accessibility features and software required. Natural language generation techniques have been investigated, including the use of logs of past conversations with conversational partners, data from a user's schedule as well as information about location from global positioning systems and other sensors. However, despite the frequent focus on technological advances in AAC, practitioners are urged to retain the focus on the communication needs of the AAC users: "The future for AAC will not be driven by advances in technology, but rather by how well we can take advantage of those advancements for the enhancement of communicative opportunities for individuals who have complex communication needs". == Pseudoscience ==

Some techniques masquerade as AAC, but are not legitimate. Two of these, facilitated communication and the rapid prompting method, claim to allow nonverbal people to communicate while the true source of the messages is the facilitator. Facilitated communication Facilitated communication is a scientifically discredited technique that attempts to aid communication by people with autism or other communication disabilities who are non-verbal. The facilitator guides the disabled person's arm or hand and attempts to help them type on a keyboard or other device. While advocates of the technique claim that it can help disabled people communicate, research indicates that the facilitator is the source of the messages obtained through FC, rather than the disabled person. The facilitator may believe they are not the source of the messages due to the ideomotor effect, which is the same effect that guides a Ouija board. Studies have consistently found that FC is unable to provide the correct response to even simple questions when the facilitator does not know the answers to the questions (e.g., showing the patient but not the facilitator an object). In addition, in numerous cases disabled persons have been assumed by facilitators to be typing a coherent message while the patient's eyes were closed or while they were looking away from or showing no particular interest in the letter board. Facilitated communication has been called "the single most scientifically discredited intervention in all of developmental disabilities". Some promoters of the technique have claimed that FC cannot be clearly disproven because a testing environment might cause the subject to lose confidence. However, there is a scientific consensus that facilitated communication is not a valid communication technique, and its use is strongly discouraged by most speech and language disability professional organizations. There have been a large number of false abuse allegations made through facilitated communication. Rapid prompting method The rapid prompting method (RPM), is a pseudoscientific technique that attempts to aid communication by people with autism or other disabilities to communicate through pointing, typing, or writing. Also known as spelling to communicate, it is closely related to the scientifically discredited technique of facilitated communication (FC). Practitioners of RPM have failed to assess the issue of message agency using simple and direct scientific methodologies, saying that doing so would be stigmatizing and that allowing scientific criticisms of the technique robs people with autism of their right to communicate. The American Speech-Language-Hearing Association has issued a statement opposing the practice of RPM. Soma Mukhopadhyay is credited with creating RPM, though others have developed similar techniques, known as informative pointing or alphabet therapy. , only one scientific study attempting to support Mukhopadhyay's claims of efficacy has been conducted, though reviewers found the study had serious methodological flaws. Vyse has noted that rather than proponents of RPM subjecting the methodology to properly controlled validation research, they have responded to criticism by going on the offensive, claiming that scientific criticisms of the technique rob people with autism of their right to communicate, ==In other animals==

Some similar tools have been studied in other animals, including apes, dogs, cats and parrots. While animals do not have human-style speech, it is possible that some animals could be trained to use simple communication tools, e.g., to request food or a favorite activity by pushing a button. One example of an animal that uses augmentative and alternative communication in a similar way to humans is the Australian Cattle Dog Stella. ==Notes==