Augmentative and alternative communication

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Augmentative and alternative communication (AAC) is communication for those with impairments or restrictions on the production or comprehension of spoken or written language.^[1]

Contents 1 Aided and unaided AAC 1.1 Unaided AAC 1.2 Aided AAC 1.2.1 Low-tech 1.2.2 High-tech 2 Symbols 3 Organization of symbols 4 Access 5 Rate enhancement strategies 6 Team 7 Specific groups of AAC users 7.1 Cerebral palsy 7.2 Intellectual impairment 7.3 Autism 7.4 Developmental dyspraxia 7.5 Visual impairment 7.6 Aphasia 7.7 Brainstem stroke 7.7.1 Locked-in syndrome 7.8 Amyotrophic lateral sclerosis 7.9 Parkinson's disease 7.10 Multiple sclerosis 7.11 Dementia 7.12 Traumatic brain injury 8 Early language learning using AAC 8.1 Effect on speech development 9 Multicultural aspects 10 Literacy 11 History of AAC 12 User's experiences with AAC 13 Outcomes 14 Terminology used in AAC 15 Works cited 16 References 17 External links

[edit] Aided and unaided AAC

AAC is used by individuals with communication disorders for whom speech is temporarily or permanently inadequate to meet all or some of their communication needs. Speech may be replaced or augmented by using a variety of modes including body language, gesture, vocalizations, manual sign, writing and/or augmentative communication aids.

[edit] Unaided AAC

Unaided AAC systems are those that do not require any external device for their use.^[2] They consist of nonverbal means of natural communication such as gestures, signed languages and systems, and vibrotactile codes.^[3] In general, unaided forms of communication require adequate fine-motor coordination abilities.^[3] Their use also necessitates the communication partner to have knowledge of the system.^[3]

Gestural systems can be both informal and formal.^[2] Informal gestures use body movements, facial expressions and postures to convey meaning. These are also often used to some extent by individuals as a complement to fully functioning natural speech.^[2] Formalized gestural codes are systems that lack a base in a naturally occurring language.^[2] These are found most commonly in nursing homes, hospitals and residential centres, but have also been used by children with profound cognitive disabilities.^[2] In the United Kingdom, the common gestural code is Makaton while the only formalized gestural code used in North America is Amer-Ind.^[2] Users of formalized gestural codes have approximately 2500 words at their disposal.^[2]

As forms of AAC, signed systems and signed languages have been used alone or in conjunction with speech.^[2] Manually coded forms of English (such as Signing Exact English, Pidgin Signed English) are not native to any speaker and are considered systems rather than languages. In contrast to formalized gestural systems and signed systems, signed languages (such as American Sign Language and British Sign Language) are naturally occurring languages used by Deaf language communities.^[2] Prior to 1990, sign languages were used more commonly than other unaided AAC systems.^[2] Sign languages are far less transparent in meaning than gestural codes and require more fine-motor coordination to execute.^[4] Additionally, sign languages are generally acquired at a later stage in development than gestural codes.^[2] For these reasons, sign languages are more difficult to acquire than gestures, especially by those with upper-extremity impairments.^[2]

[edit] Aided AAC

An AAC aid is any "device, either electronic or non-electronic, that is used to transmit or receive messages".^[2] The skills, areas of difficulty and communication requirements vary greatly within the AAC user community, and so an equally diverse range of communication aids exists to meet these demands.

[edit] Low-tech

Low-tech communication aids are defined as those that do not need batteries or electricity to meet the user's communication needs.^[5] These are often very simple aids created by placing phrases, letters, pictures or symbols on a board or in a book. Depending on physical abilities and limitations, users can access the device by pointing to the appropriate message with their fingers, a non-electronic pointer, such as a head or mouth stick, or by eye gaze.^[5]

Low-tech aids are limited in terms of the amount of messages they can convey: only so many messages can be placed on communication board or in a communication book. In comparison, natural speech can convey infinite messages, and many high-tech aids are only limited in terms of their memory store.

[edit] High-tech

High-tech AAC aids are electronic devices that permit the user to communicate with others by producing digitized or synthesized speech, or by typing out messages.^[5][6] These devices can also be referred to as Speech Generating Devices (SGDs) or Voice Output Communication Aids (VOCAs).^[5] A diverse array of such electronic devices is available and each user is matched with the assistive hardware and software most suitable for their needs, skills and abilities. ^[5]

High-tech devices vary in price, size, and amount of information they can store. They also vary in portability, with some devices being smaller and lighter than others. Devices can generally be mounted on a wheelchair if necessary. There are multiple ways to access the device, including touch screens, switches, joysticks, on-screen keyboard layouts, head-operated mice or programs that track the eye gaze of the user.^[6] The specific access method will depend on the skills of the communicator.^[6] Since electronic devices operate on batteries that need to be frequently changed or charged, and may breakdown, users usually also require access to a low-tech communication system.^[5]

[edit] Symbols

The symbols for communication with unaided AAC are gestures or hand signals.^[7] For instance, shaking or nodding the head, pointing and smiling are all gestures of communication.^[8] The benefits of these symbols are that they are always available to the user, usually understood by the listener, and are efficient means of communicating.^[8] In sign systems, the symbols are hand signals which can be iconic (they resemble the word they represent) or more abstract.^[8] With this system, the communication partners need to understand the signs for successful communication. As well, the user’s ability to control gross and fine motor movements needs to be considered with these approaches.^[8]

Aided AAC uses symbols such as pictures, line drawings, letters, and words.^[7] Symbols can be used in one form or multiple forms together such as on high-tech devices which incorporate pictures, letters, and words. Pictures are helpful symbols for people who cannot read or write. Pictures systems can have linguistics characteristics such as in Blissymbols, or without linguistics characteristics such as in the Picture Communication System (PCS).^[9]

In single meaning pictures, each word in the vocabulary is represented by a different picture. The meanings of the pictures are often naturally represented, such as in PCS, but some meanings need to be taught.^[10] Alternatively, the pictures can be more abstract representations of words such as with the Rebus vocabulary.^[10] Picture symbols can also represent multiple meanings such as in a semantic compaction system. In this system, pictures are sequenced together to form specific vocabulary.^[8]

Symbol systems also have a variety of vocabulary sizes.^[10] For example, PCS has 3000 symbols and Pick’n’Stick has 800. Symbols can be realistic pictures in color or in black and white, or simple line drawings. Some users understand the line drawings better than detailed colorful pictures or vice versa.^[8] Also, some symbols have the meanings written below the pictures.^[10] It is important to consider the individual user’s preference, visual acuity, and visual processing of information when establishing which type of pictures are appropriate for their communication system.^[8]

Symbols can be strictly visual when located on boards or screen displays or they can be tactile such as with the Picture Exchange Communication System (PECS).^[8] With this system, the pictures are on cards for the user to move around to form a message. Tangible items can also be part of symbol systems, such as miniature objects representing their real counterpart, or small items as abstract representations.^[10]

Both low and high tech devices may use alphabet-based symbols including individual letters, whole words, or parts thereof.^[10] Literacy is required for these symbols. In low-tech devices, the communication partner may see the symbols, such as with an alphabet board. In high tech devices such as Voice Output Communication Aids (VOCAs), the device will read the message put together with symbols out loud.^[10]

[edit] Organization of symbols

Within an AAC system, symbols must be organized to facilitate efficient and effective communication. This is especially important when the individual has a large number of symbols in his or her AAC system.^[2] Vocabulary organization refers to the way pictures, words, phrases, and sentences are displayed.^[11] AAC systems are usually organized in either grid displays or visual scene displays.

Grid displays are made up of individual symbols, words, phrases, or pictures. There are three types of grid displays: semantic-syntactic, taxonomic, and activity.^[2]

Semantic-syntactic grid displays have vocabulary items organized by spoken word order or frequency of usage.^[12] A common example of this type of grid display is a Fitzgerald key, which organizes symbols on a display from left to right into categories labelled who, doing, what, where, and when, with frequently used phrases and letters clustered along the top or bottom of the display.^[13] The use of semantic-syntactic displays has been shown to facilitate language and literacy skills in children.^[14]

Taxonomic grid displays group symbols according to categories, such as people, places, feelings, foods, drinks, and action words.^[2] Research conducted with typically developing children found that this type of organizational strategy is not helpful or useful until they reach at least the age of 6 or 7.^[15] As such, this strategy may not be appropriate for individuals who are developmentally younger than 6 years of age.^[2]

The activity display organizes vocabulary items according to specific situations.^[2] These can include items that are related to an activity (i.e. going grocery shopping) or routines within that activity (i.e. making a list, paying for items at the cash register).^[16] Each display contains symbols for the people, places, objects, feelings, actions, and other relevant vocabulary items for an activity or routine. These vocabulary items are then usually grouped into semantic categories (i.e. all of the action words are in one area).

Visual scene displays are depictions of events, people, objects, and related actions that are parts of a particular scene.^[2] They are similar to activity displays, as they contain vocabulary that is associated with specific activities or routines. For example, a photo of a child’s room could be included in the child's AAC system. Objects and events within the photograph could then be used as symbols for communication. For example, the symbol for "play" could be accessed by selecting the toy box, whereas selecting an individual toy would access the name of the toy.^[17] Research suggests that visual scene displays are easier for young, typically developing children to learn and use, when compared to taxonomic and activity grid displays.^[18][19]

Symbols can also be arranged in a hybrid display, in which both the grid and visual scene dispays appear together.^[2]

There are two other strategies which can be used to organize symbols within an individual's AAC system. In the first strategy, vocabulary items are organized based on the frequency of the words and messages used by the individual. This frequency-based organization divides vocabulary into two main types: core and fringe. Core vocabulary includes words and messages that occur frequently and show a high degree of commonality across users ^[2] This type of vocabulary carries little information, but provides a framework for language,^[20] and includes many function words. Conversely, fringe vocabulary refers to words and messages that are specific to an individual. These might include names of family members and friends, locations, activities, and preferred expressions.^[2] The inventory of fringe vocabulary is large, constantly updated with new words, consists almost exclusively of content words (i.e., nouns, verbs, and adjectives), and varies widely across users.^[21] Research has shown that both children and adults use a small core vocabulary and a large fringe vocabulary.^[22][23]

In the second of these strategies, vocabulary items are organized in alphabetical order. For example, within a category labelled "food," items would be organized from left to right (i.e. "apple," "banana," "cantaloupe"). This strategy can only be employed with an individual who has adequate literacy skills.^[10]

[edit] Access

Traditional communication is accessed through the mouth (by speaking), the ears (by hearing), the eyes (by seeing), and the brain (by appropriately processing meaning). People with impairments to any of these organs may require augmented or alternative access to communication. AAC access entails a complex interrelationship between the features of the AAC technology, the individual's physical abilities (e.g. motor, sensory, perceptual, cognitive and linguistic skills), and the device users' and their communication partner's abilities to interact.^[24] Use of AAC methods involves learning to select messages or codes from a relative set of possibilities. The user can use these elements alone or in combination (e.g. in natural speech, messages are produced with a combination of sounds) in order to communicate a variety of messages.^[25] The selection set of an AAC system may include visual, auditory,or tactile presentation of all messages, symbols and/or codes available to the user. The display of a selection set depends on the technique and device employed in the AAC system. Displays consist generally of one of the main three types: fixed, dynamic, and hybrid. The selection set called "scene display" has been available recently.^[26] The term fixed display refers to any display in which symbols are fixed in a certain location; they are typically used in low-tech communication boards, as well as in some speech-generating device. The number of symbols included in a fixed display is limited. In order to compensate for this limited vocabulary choice, compensatory strategies for AAC have been introduced. One of these strategies involves organizing the display into multiple levels. Other various encoding strategies have also been developed, in which a person can express multiple messages by combining one to three (or more) symbols on their fixed display.^[26] The term dynamic display is used to refer to computer screen display with electronical symbols that, when activated, automatically change the selection set on the screen to a new set of symbols. A wide variety of AAC products offer the option of dynamic display.^[26] The hybrid display refers to an electronic fixed display combined with a dymamic component, such as indicator lights, that informs the user which items of the selection set are available for activation. AAC specialists have designed this kind of technical support as a memory aid, relevant for individuals who use numerous icon sequences to produce messages.^[2] Finally Visual Scene Display (VSD) is a picture, photograph, or virtual environement that represents a situation, place, or specific experience.^[27] Encoded messages with the names of people, objects,actions, etc., are accessed from the pictures. In both low and high-tech devices, VSD makes important use of photographs to reduce cognitive and linguistic demands on the individual. This kind of display is an interesting option for young children and adults with significant cognitive/linguistic limitations.^[24]

Technological development in direct selection and scanning have dramatically increased access to AAC technologies for individuals with a wide range of communications needs.^[24] These individuals demonstrate great variability in their physical abilities, with respect to gross and fine motor control, posture, muscle tone, abnormal reflexes, etc. In most cases, abnormal tone and movement patterns lead to difficulty achieving consistent, accurate, non-fatiguing access.^[24] Some people with severe communication impairments can use their hands to access AAC; others who cannot do so use alternatives such as mouth sticks, head sticks, switches or eye pointing. Direct Selection refers to a selection made by pointing to the desired symbol using a finger or an alternative pointing technique (i.e., head pointer, eye gaze, joystick, mouse). Because many individuals who rely on AAC devices have motor control capacity limitations, they must use one of the alternative activation strategies: timed activation, release activation, or filtered activation.^[26] Timed activation strategies require the person to identify an item with finger or other pointing devices and then hold the contact for a predetermined period of time, so the selection is recognized by the system. With the release activation method, the user needs to contact the display and retain this contact until the desired item is located. Only then, this person releases contact from the display for selection of the item.^[26]

Whenever AAC users are unable to choose items directly from the selection set, mostly due to lack of motor control, they must use an indirect selection technique called scanning, whereby the items displayed for selection are scanned visually or orally by the communication partner or by the device. When the desired message is reached, the AAC user indicates his or her choice by using an alternative selection technique (i.e. switch access, head nodding) to confirm the choice.^[26] The different types of scanning patterns available are: circular scanning, linear scanning, and group-item scanning. Circular scanning is the least complex pattern in which the device displays individual items in a circle, scans them one at a time, until the user selects a desired item. Although this pattern is visually demanding, it is relatively easy to understand. That is why it is often introduced first to children or beginning AAC users.^[26] In Linear scanning a cursor light or an arrow moves across each item in the first row, the second row, the third row, and so on, until an item is selected. In auditory linear scanning, a synthetic voice or human facilitator states items aloud one at a time until a selection is made. Although more demanding than circular scanning, it is still easy to learn.^[26] Finally, group-item scanning involves identifying a group of items , followed by eliminating options until a final selection is made. One of the most common group-item strategies is row-column scanning in which each row of the visual display represents a related group of items.^[26]

The selection control techniques involve three main types: Automatic scanning, inverse scanning and step scanning. In Automatic scanning, the scan proceeds at a pre-determined speed and pattern; the individual makes the selection using a control interface (e.g. switch).^[26] As for inverse scanning, the switch must be held down to advance the scan, and then relased to make the selection. The scanning method called step scanning involves an indicator or cursor moving through a preset selection, one step at a time, for each activation of the switch.^[26] Direct access should always be the first choice when feasible because it is easier to learn. However, it requires greater movement control from the user. Therefore, indirect access is only used when all other direct access method are impossible, as it requires less voluntary movement control but is more demanding cognitively and requires motivation for learning. The user's visual acuity and visual-perceptual discrimination skills will affect the presentation of the symbol system on the AAC device (e.g. determining the size of the graphic symbols or the background-figure contrast).^[28] Research by Blackstone (2005) found that approximately 48-75% of children and adults with developmental delays and cerebral palsy, and 75-90% of children with severe and profound cognitive disabilities, had significant visual problems.^[24]

[edit] Rate enhancement strategies

Augmentative and alternative communication is generally slower than speech.^[29] Rate enhancement strategies increase the user's rate of output, and as a result enhance the efficiency of communication. There are two main options for increasing the rate of communication for AAC devices: encoding and prediction.^[29]

Encoding is the way a user is able to produce messages using the device. If an entire word, phrase or sentence can be retrieved with a one or two symbol or letter code, communication will occur faster.^[29] Some examples of encoding rate enhancement strategies are as follows: Iconic Encoding uses pictures, line drawings, or shapes to represent frequently used concepts. This is especially useful for non-literate users, as it gives them access to large vocabularies while requiring fewer keystrokes and minimal spelling or reading abilities. For example, a picture of a toilet may represent “I need to use the bathroom”.^[30] Semantic Compaction (Minspeak) uses icons with multiple meanings that are sequenced together. The meaning of the message is then dependent upon each icon in a particular sequence. For example, typing “food + yellow + B” may represent “banana”.^[30][31] Letter Encoding/Abbreviation-Expansion stores words, phrases or sentences as abbreviations, which eliminates having to type complete words or phrases. For example, typing “HH” may represent the greeting, “Hello, how are you?”^[31] Finally, Alpha-numeric/Numeric Encoding stores messages under combinations of letters and/or numbers. For example, typing “G1” may represent "Greeting 1", producing "Hello, how are you?”.^[30]

Prediction refers to the ability of the device to guess the word that is being typed by the user and to provide choices in message output. When the prediction is correct, the user selects it and no longer has to type the entire word. The user is also provided with additional choices to select in case the initial guess is incorrect. The word prediction software may determine the possible choices offered based on frequency in language, word association, past choices, or grammatical suitability.^[29][31] Some examples of prediction rate enhancement strategies are the following: Word Completion allows the device to predict the end of a word based on the first letters typed and a menu of likely words is offered based on the user’s initial keystrokes. If the desired word is offered, the user can select it without the need to continue typing the rest of the word. For example, if the user types “h-e”, “hello" or "help” may be offered as choices to complete the word.^[29][30][31] The Next Word Prediction strategy allows the device to predict words based on word pairings and/or grammatical rules of the words occurring before it. For example, if the user types, “I am”, the device may offer typical responses to this sequence of words such as “going", "feeling".^[29] Lastly, there is Linguistic Prediction, a method that allows the device to offer words that agree in tense, case and number based on previous words in the message. For example, if the user has typed “tomorrow”, only words in the future tense will be offered as choices.^[29]

[edit] Team

A comprehensive evaluation of a user's unique abilities and requirements is necessary in order to implement appropriate intervention and match the user with the most appropriate AAC device. AAC evaluations are conducted by specialized multidisciplinary teams consisting of a speech-language pathologist, occupational therapist, physiotherapist, social worker and a physician.^[28][32] The assessment team conducts interviews with the user, family members, caregivers and/or teachers in order to obtain additional information about the user's behaviour and skills in different settings. The team also assesses the user's motor abilities, communication skills, cognition and vision.^[32]

During the intervention process, the occupational therapist assists with the positioning and seating adaptations for convenient AAC access. The physiotherapist works on motor development training. The speech-language pathologist's role is to teach the user and their communication partners how to use the AAC device, encouraging the use of natural speech when possible. In selecting and adapting the AAC device for the user's individual needs, the speech-language pathologist's goal is to ensure that the AAC device can be used in different contexts and with different communication partners.^[28]

[edit] Specific groups of AAC users

Whenever possible, AAC devices should be designed for Dynamic Diversity,^[33] where the interface is accessible not only to “typical” AAC users, but also to minority populations who need to use the device.

[edit] Cerebral palsy

Cerebral palsy is a developmental neuromotor disorder that is the result of a non-progressive abnormality of the developing brain.^[28] The motor deficits associated with cerebral palsy (CP) cause speech disorders in 31% to 88% of CP patients.^[28] In addition to communication needs, practitioners must also take the particular motor challenges of the individual into account when planning the set-up of the AAC device. With this population, professionals such as speech-language pathologists, occupational and physical therapists, orthotic specialists and rehabilitation engineers are essential in the assessment process. They need to consider specific positioning and seating adaptations so that the individual can have the best access to the AAC system. For example, an individual with spastic arm movements might need a key guard on top of a keyboard or touch screen to minimize the chance of selecting a wrong button. Those with athetoid CP who have difficulty regulating movements may benefit most from an AAC device with an eye tracker.^[28]

This population often faces an additional communication challenge, in which family members and peers tend to direct and control conversations. Consequently, children with CP may not use their AAC aids as often. This has the potential to lead to delays or failure to develop the 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.^[34][35] It is essential for the AAC team to prevent the development of learned helplessness in children with CP that can result from being passive communicators.^[28] Early intervention with the speech-language pathologist targets situations that teach children with CP how to develop their conversational skills, how to communicate effectively with others, and how to control their environment through communication. It is also important for children with CP to have extensive practice using their AAC system for making choices, decisions and mistakes.^[28]

[edit] Intellectual impairment

Intellectual impairment (also known as mental retardation) is described by the American Association on Mental Retardation (AAMR) as a condition that is characterized by:

Significant limitations both in intellectual functioning and in adaptive behaviour as expressed in conceptual, social, and practical adaptive skills. This disability originates before age 18.^[36]

This description emphasizes the degree of support that an individual needs, rather than their ability level, thus recognizing the effect that appropriate supports can have on an individual’s day to day functional skills.^{[citation needed]} Even though AAC and communication services is currently more widely accepted for individuals with intellectual impairment,^[37][38] prior to the mid 1980s, these individuals were often excluded due to a failure to demonstrate prerequisite skills (most of which were cognitive in nature) thought necessary to succeed with AAC or due to existing or potential speech skills because of the notion that AAC will interfere with speech development.^[39] However, in a recent comprehensive literature review, evidence from research studies found that AAC users did not decrease in the development of speech production. In fact, the majority of cases demonstrated significant gains in speech skills.^[40] Since then, the use of various levels of AAC devices for this population has been substantiated in the literature. From simple single-switch VOCAs to dynamic displays with visual scenes, studies have shown that appropriate use of AAC devices can modify classroom, home, and social environments for children and adults with intellectual impairments to increase participation,^[39] make choices,^[41] enhance communication skills,^[42][43][44] and even influence the perceptions and stereotypes of communication partners.^[39]

While most individuals with intellectual disabilities do not have concomitant behavioural problems, it is known that behavioural problems are typically more prevalent in this population than others.^[45] In the past, strategies to “manage” the behavioural problems of those with intellectual impairments included incarceration, medication and aversive behaviour modification techniques.^[46] However, since the mid 1980s, greater emphasis has been placed on proactive strategies to prevent situations that may trigger behavioural problems before they arise. These strategies include teaching functional communication skills to individuals as an alternative to “acting out” for the purpose of exerting independence, taking control, or informing preferences. This paradigm shift in the management of behavioural problems for this population has placed new emphasis on AAC because many of these individuals do not have functional speech for communication.^[46]

Still, individuals with intellectual impairments are faced with a challenging predicament in their efforts to develop communication skills. Generalization (the transfer of learned skills into daily activities) is a common difficulty in individuals with intellectual impairments; however, AAC training is often conducted in highly structured settings rather than natural situations where skills are required.^[46] They often lack naturally occurring communication opportunities and frequently live and work in segregated environments where social interactions involve other individuals with communication impairments or staff workers who are hired to accommodate to their needs. One of the greatest needs in this population is responsive communicators with whom they can interact in the home, school and community environments.^[46] As such, AAC intervention for this population takes in account opportunities for integrated, natural communication opportunities, and vocabulary selection and instructional techniques are a reflection of each individual’s access to particular types of communicative opportunities.

There is great diversity in types of syndromes and conditions that result in intellectual impairments and within this wide range of diagnoses are varying degrees of communication impairments. Therefore, AAC interventions are very individualized and need to take into account specific abilities of language comprehension, social-relational characteristics, learning strengths and weaknesses, and developmental patterns for specific types of intellectual disabilities.^[46] In addition, the co-occurrence of multiple conditions further complicates the evaluation and prioritization of each individual’s profile and specific intervention goals.

[edit] Autism

Autism is a disorder distinguished by qualitative impairments in communication and social interactions. Children with autism may exhibit both receptive and expressive language difficulties, and they typically have more difficulty acquiring expressive skills.^[47][48] Children with autism may have no spoken language or may exhibit a delay in use of spoken language or gestures. Children with autism have been found to have strong visual-processing skills, making them ideal candidates for an AAC device.^[49] The role of AAC for this population is to improve and enhance what functional communication the child has, not to replace what already exists.^[49]

It has been found that some children with autism will express protests and requests, while joint attention or social communicative intentions are usually lacking. A child may be motorically capable of producing speech, yet lack the prerequisites for language or the social communicative base on which language is built.^[47] Therefore, if a child presents with an uneven developmental profile, intervention first begins by targeting the prerequisites for language (joint attention, verbal and motor imitation, turn-taking, etc) to begin to establish some form of functional communication.^[2][47] AAC intervention is directed towards the linguistic and social abilities of the child.^[2] If an AAC approach has begun before the child has established the precursor language skills, it will most likely result in stereotypical, non-functional behaviours and inappropriate use of the AAC device. Therefore, it is important that some functional communication exist to set the groundwork for communication and to make the best use out of the AAC device.^[49] It has been found that children with autism who have established joint attention and who can also point are able to deal with at least 50 symbols on a communication board. If joint attention has yet to be established, they can handle 2 to 6 symbols on a communication board.^[50] Some goals of the AAC device include providing the child with a concrete means of communication, as well as facilitating the development of interaction skills.^[47][49]

An AAC device is recommended for any nonverbal child, since all individuals need to be able to communicate. It has been shown that speech acquisition by the time children enter school is one of the most significant predictors of outcome for children with autism.^[47] Thus, early intervention with an AAC system is essential and is necessarily kept simple and easy to master.^[2][49]

AAC systems for this population will generally begin with communication boards as well as with object or picture exchanges such as the Picture Exchange Communication System. AAC methods can be used in conjunction with other methods, such as direct speech therapy. There currently exists little empirical evidence related directly to speech treatment.^[47]

There has been much debate about which AAC device is most appropriate for this specific population. Son, Sigafoos, O’Reilly, and Lancioni (2006) compared the use of a voice-output communication aid (VOCA) to a picture-exchange system and found that each were plausible options for children with autism, as the ease and speed of acquisition of both systems was similar among all participants.^[51] Therefore, it is feasible to consider the child’s preference before starting AAC intervention.

[edit] Developmental dyspraxia

Developmental dyspraxia is a childhood motor speech disorder involving impairments in the motor control of speech production, typically causing impairments in motor programming and execution. Major symptoms include difficulty with speech imitation, a reduced ability to produce rapid, repeated oral movements, problems initiating movements for speech, and difficulty producing sounds in sequence.^[52]

The speech of a child with developmental dyspraxia may be unintelligible to the point that daily communication needs cannot be met and that the child experiences great amounts of frustration. In such cases, AAC can be a secondary strategy to support successful communication attempts in these children, with the hope that speech will improve with time and eventually be able to meet daily communication needs. Research indicates that AAC use with this clientele does not reduce speech skills, and that it may even improve speech with time.^[53] AAC interventions in this population are made alongside more traditional speech therapy to improve natural speech production.^[53]

A wide variety of AAC systems have been used with children with developmental dyspraxia.^[54] Manual signs or gestures are the most frequent unaided AAC system introduced to these children, and can include signing unintelligible target phonemes (using fingerspelling) in concert with speech. Articulation and sequencing errors in speech have been shown to decrease in these children with the use of manual signs.^[53] While advantages of this system include its portability and unlimited vocabulary potential, disadvantages include potential problems with fine and gross motor skills, as well as the possibility that most of the people interacting with these children will not be able to understand the signs being produced.^[54] With familiar communication partners, total communication approaches may be beneficial for these children, such that signs and words are used simultaneously.^[53] With total communication, the child has the ability to be understood through sign, while continuing to attempt to successfully produce speech.

The main aided systems used with children with developmental dyspraxia include picture symbol communication boards or books, and voice output devices.^[54] While communication boards (or books) are portable and can be tailored to meet the needs of various communicative contexts, they limit the user's ability to communicate to the topics made available by the board.^[55] Voice output devices provide the user with a much greater vocabulary and ability to converse about a wider range of topics. In addition, they allow the user to generate grammatical sentences, rather than pointing to pictures one at a time.^[53]

A multimodal approach is often chosen, such that more than one AAC option is introduced to the child. This way, the child is not only given the opportunity to experiment with various aided and unaided AAC systems, but can also take advantage of certain systems that may be better than others in certain contexts.^[53] For example, voice output devices may work well during dinner, but the child may need to make use of manual signs while in the bath.

[edit] Visual impairment

High and low tech AAC systems require modification in order to make them accessible to AAC users who are blind or who have visual impairments. Modified visual output includes large print and/or clear simple graphics, and can be of benefit to AAC users with some residual vision.^[33] Tactile/tangible symbols are textured objects, real objects or parts of real objects that may be included on an AAC device for individuals with visual impairment.^[56] Braille is an example of a tactile/tangible reading and writing system.^{[citation needed]} Tactile/tangible symbols should be considered meaningful to the AAC user, thus allowing them access to language. They can be used on low or high tech displays and switches. A limitation of using tactile/tangible symbols is that they may decrease the number of symbols available to the AAC user at one time.

Auditory symbols are those that produce a meaningful sound when activated, and are thus useful for AAC users who have vision impairments. Morse Code is an example of an auditory symbol system, where long and short tones represent letters, words, and phrases.^{[citation needed]} There are some AAC devices that can convert Morse code into text or speech.^{[citation needed]} Speech is another example of an auditory symbol that can be integrated with assistive technology for the blind and visually impaired.^[56] Auditory scanning is an access method that utilizes speech with an AAC device. It presents options to the user by pronouncing them out loud and allows the users to select the desired option upon hearing it. This can be helpful for users with visual impairments who are unable to scan options presented visually.^[57]

[edit] Aphasia

Aphasia is the result of an impairment to the brain’s language domain affecting production, comprehension, or both.^[58] Aphasia occurs in up to 40% of individuals following brain injury, and can cause severe, chronic language impairment.^[58] Language intervention for individuals with aphasia typically involves efforts to reduce the language impairment, but many do not recover to the point where their language is sufficient for functional communication.^[58] AAC can help individuals with aphasia to communicate using a variety of means, including a combination of speech, gesture, or other devices.^[59] Individuals with aphasia may use different AAC methods over time as their needs and skills change.^[59]

Individuals with aphasia may use low-tech AAC interventions such as communication and remnant books, drawing, photography, written words and messages, and written choices.^[58] Individuals with aphasia can also use high-tech AAC interventions such as Voice Output Communication Aids, keyboards, or pictographic grid displays.^[58] Visual scenes have been designed for adults with chronic, severe aphasia to use with high-tech devices.^[58] The visual scene allows elements to be illustrated in relation to its natural environment. Examples include photos of events or people that are meaningful to the individual. These give context to the display and allows for mutual understanding and multiple communication exchanges to take place between conversation partners.^[58]

Supported Conversation for Adults with Aphasia (SCA) is a program developed by The Aphasia Institute in Toronto, Canada.^[60] Its purpose is to train communication partners for adults with aphasia on the techniques and resources that can be used to facilitate conversation as well as to acknowledge and reveal the competence of individuals with aphasia.^[61] Conversation partners are trained to use resources such as writing key words, providing written choices, drawing, and using items such as photographs and maps to help the individual with aphasia produce and comprehend conversation.^[62]

[edit] Brainstem stroke

Strokes that occur in the brainstem are less common than those within the cerebral hemispheres; however the true incidence is unknown.^[63] These patients' use of AAC devices is dependent on the severity of the stroke. Many experience minimal functional or cognitive deficits and require no rehabilitative services. Alternatively, those who experience catastrophic strokes within the pons have low survival rates. Those who do survive will suffer from profound deficits, including locked-in syndrome.^[63]

[edit] Locked-in syndrome

Locked-in syndrome is a neurological condition that occurs following an injury to the brainstem. Cognitive, emotional and linguistic abilities remain intact; however, all voluntary motor abilities are lost.^{[citation needed]} Vertical eye movements are the only commonly remaining voluntary motor movement.^[64] Total recovery is very rare however slight improvements are possible.^[65] The patient may live in this ‘locked in’ state for several years.

A majority of patients will need to rely on AAC strategies to communicate, since few recover intelligible speech or functional voice.^[66] The types of AAC devices vary depending on the time post-stroke, the residual motor capabilities and the preference of the individual. Communication is mainly expressed through blinking, as well as vertical or horizontal eye movements, as the ocular cranial nerve is generally unaffected in a brainstem stroke.^[64] Low-tech alphabet boards are often introduced immediately following the stroke in order to provide the individual with a means of basic communication. The alphabet can be read out by a communication partner, with the AAC user signaling that the desired letter has been reached. When vertical and horizontal eye movements are efficient, the conversation partner can hold a transparent alphabet board at eye level between himself and the AAC user. The AAC user communicates the message by focusing his eyes on the desired letter, while the communication partner moves the board until their eyes meet.^[64] These methods can be very slow and require intense concentration, patience and good memory on the part of the communication partner.

The main challenges in designing a high-tech AAC device for those with locked-in syndrome are the lack of voluntary muscle activity and difficulties in visual focusing.^[64] The use of computer-based communication requires that the patient have good memory, alertness and linguistic ability.^[64] In order for the patient to effectively operate a computer, a multidisciplinary team must find a voluntary, reliable and easily controlled muscle movement. This can be the slightest movement of a finger, wrist or chin, a frowning of the forehead or biting.^[64] This movement activates a switch, which in turn activates the computer. If the patient has good head control, an ultrasound or infrared head mouse activates the computer instead of a switch.^[64] Those who do not have stable head movement require extensive practice to control the AAC device accurately. Laser pointers paired with laser-sensing surfaces have been shown to increase the accuracy and consistency of head movements.^[66] Examples of assistive hardware and software used with this population include word prediction programs which reduce the effort required to write; speech synthesizer programs which convert written text into speech; or replacing a regular keyboard with an on-screen keyboard layout activated by a switch or head-mouse.^[64]

[edit] Amyotrophic lateral sclerosis

Amyotrophic Lateral Sclerosis (ALS) also known as Motor Neurone Disease is a progressive condition whereby the motor neurons required for smooth, voluntary movements slowly break down, leading to weakness and eventual paralysis. Approximately 75% of people with ALS will be unable to speak by the time of their death.^[67] Given the rapid progression of the disease, those diagnosed with ALS require information about various AAC options as early as possible, in order to acclimatize to the device before it is needed as a replacement for natural speech.^[68] Generally, AAC is necessary when speech intelligibility becomes inconsistent, especially in adverse listening conditions (i.e.: a noisy restaurant).^[67] In most cases, this happens when speaking rate drops to 100 words per minute.^[69] In the early stages of ALS, AAC may only be necessary to augment natural speech with unfamiliar partners (e.g. using an alphabet board to cue the listener to the first letter of the word being spoken). In the later stages of ALS, AAC often becomes the main communicative method, although familiar conversation partners may still understand a limited amount of specific spoken words.^[68] Because ALS is degenerative in nature, the choice of device has to take into account both present and future needs. Many devices can accommodate the changing motor abilities of the individual through flexible access methods. People with ALS find this preferable to changing the device itself.^[67]

In general, the ideal AAC device will depend on severity of speech impairment, functional status, and communication needs in particular environments.^[68] Lifestyle also influences the choice of device; if the person with ALS is working outside of the home, portability, durability and powered mobility are important considerations.^[68] If the user spends most of the time in a home with numerous floors, noisy children or pets, considerations about amplification become important.^[68] As cognition and vision are unaffected in ALS, writing and typing systems tend to be the most recommended and preferred devices because they allow unlimited expression.^[68] The means by which the device is accessed depends on the type and severity of the disease. In the spinal form of ALS, the limbs are affected from the onset of the disease. As a result, high-tech devices are often most helpful as they can be modified to accommodate physical impairments through a head mouse or eye tracking.^[70] Head tracking technology is improving, but a limited range of head movement may affect calibration.^[58] Eye-tracking technology is also improving; however its performance is not yet ideal in all lighting and postural conditions.^[58] In addition to these high-tech options, low-tech systems, such as eye gazing or partner-assisted scanning, are used in situations when electronic devices are unavailable (i.e.: during bathing).^[68] In the bulbar form of ALS, speech is affected before the limbs. As a result, handwriting is often the first course of AAC. As the disease progresses and starts affecting hand movement, writing or typing VOCA devices may be optimal, as these require less manual dexterity, while still offering full freedom of expression. In the final stages of the disease, eye gaze and partner-assisted scanning are preferred as they carry the added benefit of promoting social closeness.^[68]

[edit] Parkinson's disease

Parkinson’s disease is a progressive neurological condition in which no initial speech disorder may be present.^[2][71] Motor problems may be present including a resting tremor, bradykinesia, reduction in movement, muscular rigidity, and disturbed postural reflexes.^[2][71] Cognitive changes may include dementia, slowed problem solving skills, visual-spatial processing difficulties, and depression.^[2][71] Later in the disease progression, hypokinetic dysarthria may result with symptoms including reduced loudness, monopitch, decreased speaking rate with some rapid bursts of articulation, harsh and breathy voice quality, and imprecise articulation.^[69] Some individuals with Parkinson’s disease will eventually lose all functional speech.^[2] Other communication problems may include reduced use of gestures and facial expression, micrographia, word finding difficulties, and reduced self-monitoring of intelligibility.^[71]

AAC interventions with this population take future speech, motor, and cognitive decline into account.^[2] Most individuals with Parkinson’s disease are able to communicate using natural speech to some degree for most of the disease progression, and so a multimodal approach is often used, involving both natural speech and an AAC device.^[2] Some individuals with Parkinson’s disease might be resistant to AAC intervention because they may be unaware of the extent of their communication difficulties.^[2][72] Hence, supportive communication partners and counselling with regard to the progressive nature of speech loss and the supports that are available are necessary.^[2]

AAC intervention for this population may include increasing overall loudness, decreasing speech rate, and/or improving intelligibility.^[2] A portable amplifier increases the volume of a person’s voice.^[2] To increase intelligibility, people with Parkinson’s disease are often taught to use an alphabet board supplementation technique where they point to the first letter of each word.^[2] This helps to decrease speech rate and provides visual information to the listener to help compensate for impaired articulation.^[2] This supplementation technique can also be used to overcome communication breakdown by spelling out entire words or providing the topic of conversation.^[2] Muscular rigidity with reduced range and speed of movement often necessitates an organization of the alphabet board where a smaller selection display is provided.^[2] Furthermore, their hands may need to be stabilized on the communication board to help compensate for a resting tremor.^[2] Those who are no longer able to communicate using either speech or writing, due to micrographia, may be assigned a high-tech AAC keyboard VOCA device, which may or may not include a keyguard to prevent accidental keystrokes caused by a resting tremor.^[2] Success with AAC devices in this population is variable due to speech, motor, and cognitive decline.^[71]

[edit] Multiple sclerosis

The most common communication problem in individuals with multiple sclerosis (MS) is dysarthria. Not all people with MS have communication difficulties. A 1972 study of 168 people with MS by Darley, Brown, and Goldstein found that only 41% had abnormal speech.^[2] Further, a survey of 656 people diagnosed with MS found that even fewer required the use of AAC systems, and only 4% reported that strangers were not able to understand them.^[73] The progression of MS can be relapsing/remitting, chronic progressive, or a combination of the two. By the time that speech becomes so impaired as to require AAC intervention, individuals with MS are usually no longer able to continue with their work or schooling. Thus, AAC intervention with this population usually focuses on meeting conversational needs.^[2]

Individuals with MS vary widely in their motor control capacity, and methods of access to AAC technology are adapted accordingly. The presence of upper limb intention tremor may interfere with the use of a device, but sometimes AAC teams can stabilize the limb, to allow the AAC user to make sufficient voluntary movements to activate a switch. Alternatively, a switch can be attached to the AAC user’s hand, so that it moves with the tremor, and is activated by a finger.^[2] Visual impairments are common in MS, and 35% of people with MS experience optic neuritis as the first symptom. AAC users with visual impairments may require devices that allow auditory scanning systems, large-print text, or synthetic speech feedback that plays back words and letters as they are typed.^[2]

[edit] Dementia

Dementia is an acquired, chronic, cognitive impairment characterized by deficits in memory and in at least one additional cognitive domain, such as language, visuospatial function, apraxia (movement), judgment or executive functions.^[58][74] Its most common form is Alzheimer’s disease.^[53] Cognitive-communication deterioration associated with dementia follows a predictive course and is divided into three stages: mild, moderate and severe.^[74] Among communication strengths are the use of syntax, following two-step commands and expressing needs when supported by a communication partner, whereas communication deficits can include reading comprehension, writing skills, word-finding, reduced verbal output and topic maintenance in conversation.^[74] Communication impairments are partly attributed to memory deficits.^[74]

AAC intervention for individuals with dementia is relatively new.^[58] Its goal is to compensate for deficits and to capitalize on the person’s strengths, hence the reason for enhancing recognition memory rather than recall memory.^[53] AAC strategies focus on reducing memory demands and use low tech devices, such as memory books, including autobiographical information and daily schedules, small wallets with photographs, and communication cards acting as reminders or labels.^[53] Multiple studies on memory books with individuals at different stages of dementia have shown positive outcomes without intensive training: increase in the number of on-topic factual statements, decrease in ambiguous and perseverative statements, and increase in the overall number of utterances in a conversation.^[75][76][77] Moreover, an investigation was carried out on the effectiveness of two training approaches (spaced retrieval and a modified cueing hierarchy) to teach people with dementia strategies to remember to use external aids, including memory books and memory wallets.^[53][77] It demonstrated the ability of individuals with dementia to acquire and maintain new information up to four months after intervention.^[77] On the other hand, a study on AAC with voice output resulted in limited topic elaboration/initiation, reduced output and heightened distraction, thus establishing a discrepancy between human-human word cueing and machine-generated word cueing.^[74]

Additional communication strategies used with people afflicted with dementia involve the communication partner’s behavior. Successful strategies include minimizing distractions, asking yes/no questions, and speaking in short simple sentences, whereas slowing the rate of speech increases communication breakdowns.^[53][78] Chunking information with augmented listening strategies, such as identifying topics of conversation with pictures, also improves the conversational skills of individuals with dementia.^[53] Dementia is expected to affect an even greater percentage of the population in the future.^[58] Further research on communication interaction and social engagement is needed to enhance the quality of life of individuals and their families living with the ramifications of dementia.^[58]

[edit] Traumatic brain injury

The communication disorders that follow from traumatic brain injury (TBI) usually fall into one of three categories: cognitive-communication disorders, social (pragmatic) communication disorders, and motor speech disorders^[79].Of those patients unable to use natural speech to meet their communication needs at the outset of their rehabilitation, 55-59% recover speech by the middle stage of recovery (Rancho levels V and VI) as part of the 'cognitive clearing' that sees a return of overall alertness, responsiveness, and a reduction of confusion^[80][81]. Those individuals who do not recover natural speech to a degree sufficient to meet their communication needs typically suffer from severe impairments related to cognition and/or motor control deficits^[82]. In some cases cognitive problems like memory impairment, disorientation, and decreased alertness may present alongside deficits in motor planning, programming, or execution. In other cases, AAC may be necessary because severe motor speech disorders--particularly dysarthria, which occurs in roughly 1/3 of TBI cases^[83]—persist where cognitive function has been speared.

Issues in AAC intervention in cases of TBI

Memory: There is a high prevalence of memory impairment following TBI. This can affect AAC use in a variety of ways. For example, patients may have a difficult time learning compensatory strategies, or they may be unable to generalize techniques they learned in the clinic to their natural communication settings^[84]. Common rate-enhancement strategies that involve abbreviated letter cues to support word or phrase retrieval are often not suitable to these patients because the coding system is beyond their abilities. In cases of high-tech intervention, patients may have difficulty recalling how to access information stored on the device ^[85].

New learning is very often affected following TBI. This can mean that individuals will need extensive support to master their AAC device. Communication partners or extensive family involvement is often required. Learning impairments often dictate the design of AAC systems, with which patients may prefer to rely on over-learned skills such as spelling messages, rather than combining words and symbols that are semantically stored and require new learning.^[86]

Initiation impairments can cause AAC users to use functional AAC systems only minimally, and not spontaneously. Initiation deficits will often prevent AAC users moving from partner-dependent to independent communicators, because they do not use their AAC system with the consistency necessary to meet their communication needs.

Assessment Principles^[87]

• Identify residual strengths and utilize over-learned skills
• Minimize new learning by using natural motor responses during assessment
• Assess repeatedly; assessment must be ongoing and dynamic
• Include family and caregivers in assessment because they affect the acceptance of AAC interventions

Levels of Intervention ^[88] Early phase: Stimulation Level The early phase of recovery (Rancho level I-III) if characterized lack of speech and inconsistent responses due to low or inconsistent levels of arousal. The general goal of intervention at this level is to improve arousal and establish consistent responses which can be shaped into meaningful communication opportunities.

Middle phase: structured level

At Rancho level V, patients may be confused, agitated, or behave inappropriately; display impairments of auditory or visual processing; and be unable to learn new information. Intervention goals at this level include: increasing the reliability of yes/no response; increasing the ability to convey basic needs; increase initiation and participation in familiar tasks; establishing responses to wh-questions. It is also imperative that this stages sees the inclusion of communication partners in the process of vocabulary and message selection, as well as training partners to use the new system.^[89]

Late phase: compensation level

Individuals at this level behave in socially appropriate ways, are able to follow a schedule, and are able to functionally communicate their wants and needs in familiar situations. They tend to become confused in unfamiliar situations, and may become distracted very easily. Many have difficulty monitoring their behaviour in the conversational setting. The purpose of AAC intervention at this stage is to increase communication efficiency and to increase participation in everyday life. Goals will include: expanding the range of partners and settings in which a patient can comfortably communicate; teaching strategies to increase accuracy and efficiency of communication; mastering the basic functions of an AAC deice; increasing the patient’s involvement in setting up their AAC device.^[90]

[edit] Early language learning using AAC

Generally, children depending on a AAC system for the development of language do experience both expressive and receptive language impairments, however it is important to take into account that using the AAC device to support language development is not necessarily a contributing factor to the delays.^[2] Delays that are apparent in AAC users tend to be the result of factors relating to physical and cognitive limitations associated with the individual’s overall condition.^[2]

The following intervention strategies have been commonly used to support language learning in AAC device users:

Symbols and language A wide variety exists in terms of available AAC symbol sets and currently no one symbol set has been proven to be effective in facilitating language development.^[2] Researchers do however note the importance of using symbols that allow representation of grammatical markers that indicate tense, quantity and possession, as many AAC devices tend to be simplified in order to reduce the cognitive load of the communicative task on the user.^[2]

Organizational strategies Several organizational strategies are used in order to promote efficient and effective communication to encourage language learning. Two main categories exist: grid displays and visual scene displays

Additional intervention methods implemented with AAC users such as the Instructional Approaches and the Interactive Models focus on enhancing specific aspects of receptive and/or expressive language development.^[2]

The Structured Method is a direct instructional strategy based on both experimental and applied behavior analysis and is implemented by an interventionist or a computer on one learner at a time. Ideally, the format of a structured strategy involves a stimulus, a prompt, a response by the learner and a reinforcer.^[2] It may be used to teach receptive and expressive labeling, and morphemic and syntactic language forms using AAC techniques,^[91] as well as a supplementary tool for other intervention methods.^[2]

The Interactive Model refers to the training programs used with typically developing children such as the Hanen Early Language Parent Program and the Prelinguistic Milieu Teaching that encourage the involvement of parents in promoting their child’s early speech and language development. Nevertheless, this type of approach could also effectively be used with children who communicate through AAC since the basis of their principles is universal.^[2]

In addition, the Aided Language Stimulation and the System for Augmenting Language, which are intended to teach comprehension and use of graphic symbols for AAC applications in a naturalistic context, have proven to be effective methods in language acquisition through a less structured training intervention.^[2]

[edit] Effect on speech development

Parents of children with developmental disabilities frequently express concern about speech development. In some cases, parents may hesitate to implement an AAC system/device as they worry that the device will become a permanent substitute for speech (ie, the child will no longer have a reason to speak if he/she can communicate using a different system).

A 2008 systematic review found that, in general, AAC interventions do not appear to impede the development of speech, and may result in increased speech production, with modest gains observed.^[92] A 2009 descriptive review found inconsistent and unclear data on whether PECS affects speech development.^[93]

Some researchers hypothesize that using an AAC device relieves the pressure of having to speak, allowing the individual to focus on communication; the reduction in psychological stress making speech production easier.^[94] Others speculate that, in the case of electronic voice output devices, the device provides a model of spoken output for children with developmental disabilities which may lead to an increase in speech production.^[95]

Parents of children who are non-verbal or have limited speech output often state that they'd like their child to use speech as his/her primary mode of communication. When discussing AAC options with a speech-language pathologist, both parents and clinicians must keep in mind that although studies have shown that AAC does not impede speech production, the gains in speech output made by the subjects have been modest,^[92] and expectations for the child's speech development should be adjusted accordingly. Further, children requiring AAC present with a wide range of abilities and disabilities, and different diagnoses as well as different developmental progressions are likely to influence the effects of AAC on the development of speech.

[edit] Multicultural aspects

Cross cultural differences should be taken into account when assessing and planning for AAC intervention.^[96] Ethnic awareness helps professionals determine which AAC system is best suited for their client.^[97][98] Providing AAC services requires the input of family, particularly for early intervention. Respecting ethnicity and family beliefs are key to a family-centered and ethnically competent approach.^[99] AAC service providers may face challenges due to their lack of information about other cultures, due to families' attitudes about their own involvement in their child's care or their loved one, and culturally specific views about disabilities in general.^{[citation needed]}From the team's perspective, respect and understanding of culturally diversity can help prevent family alienation,^[100] contribute to the selection of the right AAC system for the user,^{[101][102][103]} and to the family wanting to continue collaborating with the AAC team.^[104]

Professionals must consider the "visibility" of the device.^[105] Some cultures do not want the AAC to attract attention to the user; the need for an AAC is a private matter and they will not want to attend training sessions. These priorities may differ considerably from the AAC team's views, but they require consideration to promote cultural respect.^[106]

Culturally diverse child rearing practices influence AAC intervention.^[2] Accepting a communication aid and being labeled with a disability may be easier for some cultures which promote accessibility.^[2] Other cultures may place greater value on hierarchical family structures, politeness, indirect communication, and respect authority figures.^[2] Disability may also be viewed with a stigma; thus, folk, spiritual, and natural interventions may be preferred over modern technology.^[2] Other cultures may expect an AAC device will immediately reduce the visibility of the disability, while other cultures may prefer not to have an AAC device at all in order to reduce stigma.^[107]

When attempting to match the AAC system to the user, professionals consider several factors, including the need for the communication device to help promote self-determination, i.e., the ability to make one's own decisions and choices about one's life.^[108][109] Some cultural groups consider a child's independence as a rebellion, and do not believe children should be allowed to have greater control of their own lives.^[110] Thus, an AAC device may not be considered necessary if the goal is to increase the user's independence and promote individualism.

Cultural sensitivity may require avoiding stereotyping color and symbols, such as using black to denote "wrong" or "bad" and using culturally specific symbols and colors.^[99]

[edit] Literacy

Many children who use AAC have difficulties learning to read and write due to a variety of impairments that can affect emergent literacy. Users with motor impairments, such as cerebral palsy or spinal cord injuries, do not tend to experience significant cognitive or learning delays that contribute to difficulty with literacy development.^[111] Children with language delays lack the strong foundation for literacy learning, and may then fall behind their typically developing peers in regular classrooms that assume a certain level of language mastery.^[112] These language and literacy delays can have far reaching effects as literacy skills facilitate self-expression and social interaction in face-to-face conversation and provide opportunities to participate in home, work, school, and social settings.^[113] Furthermore, literacy fosters independence by providing access to educational and vocational opportunities.^[114]

Currently, most children who use AAC do not achieve literacy skills beyond a second grade level.^[115] Those who grow into functionally literate adults often report having access to abundant reading and writing material at home as well as in school during childhood.^[116] Engaging in rich language and literacy experiences before entering school fosters vocabulary development, discourse skills, and phonological awareness, all of which supports successful literacy learning. These experiences are even more valuable for children who use AAC as many experience vocabulary delays, short utterance length, weak syntax, and impaired pragmatic skills.^[112]

There is a common misconception that individuals who need AAC are not capable of learning to read or write.^[114][117] As a result, young AAC users are often given fewer opportunities to engage in reading and writing activities outside of the classroom, which limits the amount of time, range, and quality of experience.^[117][118] However, current research suggests that with direct and explicit reading instruction, AAC users can better develop their literacy skills, leading to more participation in academic, vocational, and community activities.^[119][120]

[edit] History of AAC

Although AAC can trace its roots back to the early days of Ancient Rome, with the first use of augmentative strategies for the Deaf, its modern inception began in the 1950s. At this time, AAC devices were mainly implemented for those whose oral and laryngeal anatomy was damaged by surgical procedures such as laryngectomies and glossectomies.^[121] There was little thought given to the use of AAC strategies for those with severe communications impairments resulting from other origins. Despite this, manual languages proliferated naturally in the Deaf community. Members of this community began to actively pursue their right to be educated using American Sign Language (ASL) during the 1960s, coinciding with the United States Civil Rights Movement. This activism helped increase public and governmental awareness of the issues related to AAC. At this time, the first academic text to discuss ASL as a true language, Sign Language Structure, was released and Total Communication, an educational approach for the Deaf, was developed.^[121]

During the late 1960s, it became acceptable to use manual sign languages with individuals who had both hearing and cognitive impairments. The use of AAC devices was also prevalent among those for whom it seemed that intelligible speech would likely never be possible, including those with severe dysarthrias, cerebral palsy and amyotrophic lateral sclerosis. However, in most cases AAC strategies were 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 communicate verbally.^[121][122]

This view continued to dominate the field until the 1970s, when several acts of government helped to expand the application of AAC strategies.^{[citation needed]} In 1975, the Education for All Handicapped Children Act (P.L. 94-142) (later renamed the Individuals with Disabilities Education Act (IDEA)) sanctioned the provision of educational services for all school-aged children with disabilities. As a result, many children with disabilities entered the public school systems, compelling classroom teachers to find ways in which to assist communicative exchanges. The 1986 Education of Handicapped Act Amendments (P.L. 97-457) promoted the use of technological devices to help accomplish the aforementioned goal.^[121][122]

During the beginning of the 1980s, AAC became an area of professional specialization. Articles, newsletters, and textbooks on the matter were published as well as the first international conferences. The American Speech-Language-Hearing Association published a position paper regarding AAC as a field of practice for speech-language pathologists in 1981, and in 1983, the International Society for Alternative and Augmentative Communication(ISAAC) was founded.^[121]

The Technology-Related Assistance for Individuals with Disabilities Act (P.L. 100-407) was announced in 1989 and declared that all states make every possible effort to provide access to assistive devices and technologies to citizens, regardless of age, disability, or location of residence. A variety of other acts at the time sought to highlight the importance of disseminating information regarding assistive technologies and the right to their access to the general public. In 1992, the Communication Bill of Rights, set forth by the National Joint Committee for the Communication Needs of Persons with Severe Disabilities, stated that all individuals with severe communication disabilities have a right to use AAC devices at all times as well as a right to information and the opportunity to have and make choices.^[121][122]

Since the 1990s, there has been an increase in in-class and natural education techniques, as opposed to traditional pull-out methods, which has led professionals to seek ways for children with disabilities to participate more comprehensively and successfully in classroom activities. This inclusion model promotes the enrichment of functional skills taught within a natural context. The 1997 amendments to the Individuals with Disabilities Education Act (previously the Education for Handicapped Children Act) mandated individual assessment of children’s assistive technology needs, including augmentative communication as well as consideration of these needs in students' Individualized Education Program. The field of AAC now follows a participation or universal model, believing that anyone can communicate and benefit through the use of AAC devices and methods.^[121][122]

[edit] User's experiences with AAC

When adults with complex communication needs enter hospitals, they often have difficulty communicating with hospital staff members, as there are many potential communicative barriers in this situation. Bed-ridden individuals who cannot access an AAC system may not have a way to communicate. Patients may not have the opportunity to communicate if the staff members perceive it as a time-consuming task. Additionally, there may be a lack of understanding on the part of hospital staff, with respect to a patient's communicative attempts. As a result, the staff may not respond to these attempts at communication.^[123] Family members tend to take over and speak on behalf of the patient to the doctors and nurses. In one study that interviewed adults with cerebral palsy (CP), it was expressed that doctors would speak to the family instead of the patient, since the patients needed time to communicate using AAC.^{[citation needed]} It was also felt that the doctors were too busy. One patient recounted a success story where his brother taught the nurse how the patient communicates with the AAC and then the patient used the AAC to communicate with the nurse directly.^[124] The implication of this scenario is that communication is possible. As long as hospital staff are aware of other communication modes (AAC), family members are willing to be less protective, and patients can have enough confidence to speak for themselves. The consensus of these interviews is that adults with complex communication needs wish to be treated like adults while they are in hospital, and they would like to be involved in decision-making about their health care.^{[citation needed]} They also want to be involved in the education of hospital staff about AAC communication.^[124] Doctors and nurses need to become familiar with AAC systems and have some knowledge/skills on how to interact with patients with complex communication needs.^[123]

[edit] Outcomes

Literacy Children with disability using Alternative Augmentative Communication (AAC) systems are at risk for impoverished literacy.^[125] The poor literacy outcomes result from poorer reading skills that these children tend to have. Their difficulty in reading stems from their limited use of speech and language. As children, AAC users often have difficulty with articulation, grammar, semantics, syntax and narration. These language elements are not only important for producing and understanding language but also for developing reading and writing skills.^[126] Since AAC users tend to have limited experience/exposure to print, they gain less knowledge about the world and vocabulary.^[127] Teachers tend to have lower expectations for reading achievements from individuals using AAC and this may affect the quality and quantity of literacy instruction they receive.^[128] Due to communication barriers, these children may have less opportunities for asking questions and to inquire about missing information in texts and during classroom book reading times. They may receive less guidance and have more limited opportunities to practice with books. The resulting poorer literacy outcomes may limit AAC users in educational and vocational opportunities.^[129]

Employment Physical disability may reduce the ability to work. Individuals with severe physical disabilities are often forced to discontinue their work. According to U.S. Census Bureau (1997), amongst the severely disabled individuals, less than 10% were employed. Despite the various barriers to employment, it is possible for AAC users to achieve success in educational endeavors and employment.^[130] Although, the types of jobs these individuals are involved in are often low-paying jobs,^[131] some AAC users also maintain higher-skilled jobs. Individuals with a severe disability like ALS using AAC have been found to continue working.^[132] Their positive work experiences were related to a positive and supportive work environment. Access to AAC, determination and a positive attitude was what helped the individuals in this study to participate in society and have a good quality of life.^[133] Personality factors that have been found to be related to employment are a strong work ethic and access to AAC technology. Family support, education and work skills are also related to positive employment outcomes.^[134] Community networks (friends and family) have also been found to help in work opportunities.^[135]

Quality of life There have been reports of AAC users to have satisfying relationships with family and friends. They can engage in pleasurable and interesting life activities and they may remain optimistic even when unemployed.^[136] There may, however be more negative post-school outcomes,^[137] especially when post-secondary education or employment are not pursued. The negative outcomes are more related to dissatisfaction with the service delivery and AAC supports, which results in communication barriers for AAC users. These issues reflect issues with policy barriers, lack of resources, and dissatisfaction with communication devices that exist for AAC users.^[138]

Coinciding with a move towards evidence-based practice within speech-language pathology and health care in general, speech-language pathologists have increasingly been interested or even required to demonstrate the effectiveness of their interventions.^[139] Within the field of AAC, this effectiveness can be measured according to a number of parameters related to the client and his or her family including participation, functional communication, consumer satisfaction and quality of life.^[2] Several tools, both general and more specific to AAC, exist to measure outcomes of intervention. The QUEST (Quebec User Evaluation of Satisfaction with Assistive Technology) is a standardized interview or questionnaire designed to assess an AAC user's satisfaction level.^[140] Another measurement tool developed by the American Speech-Language Hearing Association (ASHA), is the FCM (Functional Communication Measure). The FCM for Augmentative and Alternative Communication is a seven-point rating scale, ranging from least functional (Level 1) to most functional (Level 7). It is one of fifteen such scales that represent a continuum along which to describe the different aspects of a patient’s functional communication abilities over the course of intervention.^[141] Research projects and Data bases have also been established to advance the area of outcomes measurement within the broader field of assistive technology by improving the field’s ability to measure the impact of Assistive Technology on the lives of people with disabilities while determining the effectiveness and usefulness of devices and services.^[142]

[edit] Terminology used in AAC

Symbol: Something used to represent another thing or concept. For example, a picture or line drawing of a dog to represent dog.

Symbol Set: A set of symbol that is closed in nature; symbol set can be expanded, but it does not have clearly defined rules for expansion (e.g., Picture communication symbols).

Symbol System: A set of symbol; includes rules or a logic for the development of symbols (e.g., Blissymbols).

Speech Generating Device: An electronic assistive device that produces speech (e.g., Dynavox, Mercury).

VOCA: Voice Output Communication Aid; other term for electronic assistive device producing speech.

AAC System: An integrated network of symbols, techniques, aids, strategies, and skills.

Input Method: Technique used to select representations of the wanted utterances from an electronic device (e.g., touch screen selection, eye gaze pointing, switch access).

See also: Blissymbolics.

[edit] Works cited

• American Speech-Language-Hearing Association. (2005). ' 'Roles and responsibilities of speech-language pathologists with respect to alternative communication: Position statement. ASHA Supplement 25, 1-2.
• Beukelman, D, & Mirenda, P (2005) Augmentative & Alternative Communication: Supporting Children & Adults With Complex Communication Needs , Paul H Brookes, Baltimore
• Rowland, C., & Schweigert, P. (1989). Tangible Symbol Systems: Symbolic communication for individuals with multisensory impairments. Augmentative and Alternative Communication, 5(4), 226-234.
• Rowland, C., & Schweigert, P. (1996). Tangible Symbol Systems::Tangible Symbol Systems (DVD). Portland, OR: Oregon Health & Science University.
• Rowland, C. & Schweigert, P. (2000a). Tangible Symbol Systems: Tangible symbols, tangible outcomes. Augmentative and Alternative Communication, 16 (2), 61-78.
• Rowland, C., & Schweigert, P. (2000b). Tangible Symbol Systems:Tangible Symbol Systems (2nd Ed.). Portland, OR: Oregon Health & Science University.

[edit] References

[edit] External links

• ISAAC - International Society for Augmentative and Alternative Communication
• AAC-RERC - Augmentative and Alternative Communication Rehabilitation Engineering Research Centers
• USSAAC - United States Society for Augmentative and Alternative Communication
• Communication Matters
• AAC Institute
• ASHA AAC Information
• Rehabilitation Engineering and Assistive Technology Society of North America