Augmentative and Alternative Communication - An area of clinical practice that attempts to compensate either temporarily or permanently for the impairment and disability patterns of individuals with severe and expressive communication disorders.

AAC facilitator - All persons who aid, assist, or in some way free the individual from their severe communicative difficulties related to their physical, linguistic and/or cognitive disabilities.

AAC facilitation - Activities designed to assist an AAC user develop and maintain communicative competence in a variety of communication contexts.

AAC system - An integrated group of components, including the symbols, aids, strategies, and techniques used by individuals to enhance communication.

AAC strategy - A learned, or self-realized method of employing AAC aids, symbols, and/or techniques to effectively enhance and/or facilitate communication and/or communication potential.

Academic expectations (levels)

competitive: academic requirements similar to those of regular education students. Amount of work may be reduced, but student expected to learn comparable concepts as peers. No adjustment in evaluation expectations.
active: reduced academic expectation workload adjusted and student evaluated based upon their capabilities and modifications to the grading standards are made.
involved: minimum requirements for meeting academic standards. Student may attend classes for subjects they are interested in but are not evaluated with same criteria as their regular education peers and are graded on participation and involvement.

Access barriers - Access barriers are associated to capabilities, attitudes, and resource limitations of potential AAC users themselves.

Access strand - Refers to the individual's ability to compensate for physical or communication barriers in order to participate more fully in meaningful life activities. Memorabilia boxes- collection of personal items reminding client of special people, events, interests, etc., used to generate conversation and/or to dissuade when client's unfocused or agitated.

Accurate system - A system that the AAC user can use to produce intended messages with a minimum number of communication breakdowns and errors.

Adapted cueing techniques - Aided communication in which gestures are used in conjunction with natural speech. The gestures initiate the shape of the oral cavity and movement of the articulators, and the way a sound is produced.

Agglutination - The process in which words can be combined to create new concepts (e.g., garage = place + drive + shelter).

Aid - A physical object or device used to transmit or receive messages (communication book, chart, VOCA, etc.)

Aided language stimulation - A language stimulation approach in which the facilitator points out picture symbols on the child's communication display in conjunction with all ongoing language stimulation. It is a pairing of verbal and symbol use by the facilitator. Through the modeling process the concept of using the pictorial symbols interactively is demonstrated for the individual.

Aided symbols - Requires some type of external assistance such as a device for production of communication. (real objects, black and white line drawings, etc.).

Alphabet board supplementation - This procedure requires the speaker to point to the first letter of each word as it is spoken. It forces speakers to slow their speaking rate and provides communication partners with extra information in the form of the first letters of words.

Alpha-numeric encoding - A method of encoding in which both letters and numbers can be used to increase rate of communication. The letters can be used to specifiy a category and the number used to specify an individual message within the category.

Alternative access - Refers to how the person using the AAC system interacts with it regarding message composition and motor skills.

Amer-Ind- American Indian Hand Talk - It is a form of sign language that has 250 concepts that is equivalent to approximately 2500 English words, since each sign has multiple meanings .

Amyotrophic Lateral Sclerosis (ALS) - A progressive disease of unknown etiology involving the motor neurons of the brain and spinal cord.

Arena assessment strategies - It is an assessment strategy in which many team members observe one member conducting an assessment across the areas of motor, sensory, linguistic and cognitive abilities. Each observer observes and collects information on the assessment.

Arthrogryposis Multiplex - A chronic non progressive disorder apparently hereditary and evolving from an absence of fetal movement. This rare congenital disorder is manifested by joint immobility, weak or absent limb muscles and spinal curvature. Even with surgery, functional use of upper extremities is minimal. Individuals with this disorder usually develop normal language skills but require alternative supports for reading, writing, and computer operation.

Attention - Orienting to or directing and sustaining interest towards a person, object or activity.

Augmented-input communicator - An aphasic patient demonstrates auditory reception difficulties that require the listener to generate key words or written choices to supplement auditory input. A variety of severe aphasic patients may benefit from augmentative input communication strategies, especially those demonstrating intermittent auditory processing breakdowns.

Aural reading - This is a supplement for individuals who cannot efficiently read printed text. Also called "auding", it is the process of hearing, listening, recognizing and interpreting previously recorded language. It relies on the individual's ability to process auditory and linguistic information efficiently and accurately.

Autism - A syndrome characterized by impairment in communication skills and reciprocal social orientation/interaction, extreme resistance to change and/or control, preoccupation with inappropriate use of objects, and unusual motor patterns.

Automatic-appropriate - Level VII of the LOCF, characterized by apparently appropriate behavior that is automatic and demonstrates impaired judgment.

Awareness of contingencies - Refers to the knowledge that certain actions and behaviors can directly lead to specific outcomes, including social outcomes. Understanding this "cause and effect" often leads to intentional communication.

Basic-choice communicator - Communicative technique to be used with severely aphasic people. The aphasic person requires maximal assistance from listeners in order to make basic choices. The choices help clarify needs, facilitate participation, and develop turn-taking skills. The person with persisting global aphasia and severe neurological impairment may remain in this category for extended time.

Bulbar ALS - A form of Amyotrophic lateral sclerosis. These individuals usually experience dysarthria early in the disease process, and deterioration of their speech and swallowing functions may be rapid. Motor impairments are usually less extensive until much later in the disease process, thus they are usually able to control direct select AAC techniques using their hands or fingers.

Capability profile - The process of gathering information about an individual's capabilities in a variety of areas in order to determine the appropriate AAC option.

Centering - Related to scanning the scanning indicator automatically returns to the center of the scanner display after each selection.

Central field loss - A person with central field loss has difficulty seeing a vertical target presented at the midline of the body.

Cerebral Palsy - A developmental neuromotor disorder that is the result of a non progressive abnormality of the developing brain. Motor problems are usually present. Types of cerebral palsy include: spastic, athetosis, rigidity, ataxia, tremor, and atonia.

Cerebrovascular accident (CVA) - Disruption of blood circulation to the brain, which can result in permanent damage to brain tissue.

Circle of friends - Used to facilitate inclusion of school-aged individuals with severe disabilities into regular classroom settings. this dynamic process of including persons with severe disabilities in activities involves family members, principals, teacher, and most importantly, classroom peers.

Circular scanning - This is the simplest of the scanning patterns in which the individuals items are displayed in a circle and are electronically scanned, one at a time until the AAC user stops the scanner and selects an item.

Chart-based retrieval strategies - Codes and their corresponding messages are listed on a chart, usually alphabetic, numeric, or categorical order. It does not require the memorization of the code by the user or their partners.

Collaborative teaming - An integrative process that enables teams of individuals with diverse expertise to generate creative solutions to problems identified by all. The outcomes is enhanced, altered, and produces solutions that are different than they would be if the individuals themselves would have come up with them.

Communication participation model - This model provides a systematic process for conducting AAC assessments by looking at the participation requirements of nondisabled peers of the same chronological age and using this information to design the assessment and/or intervention. The four areas to be looked at would be: Identification of participation patterns and communication needs; assessment of barriers; plan and implementation for interventions; evaluation of intervention effectiveness.

Communicative competence - The ability to functionally communicate within the natural environment and to adequately meet daily communication needs. It is suggested that this is accomplished by the integration of knowledge, judgment, and skills in the area of linguistics, operational, social, and strategic competence.

Communicative competence for AAC user - The ability to functionally communicate within the natural environment and to adequately meet daily communication needs. It is suggested that this is accomplished by the integration of knowledge, judgment, and skills in the area of linguistics, operational, social, and strategic competence.

Communicative competency - Is the efficient exchange of messages between partners and the awareness, on the part of both partners of the social structures or interactive process in the exchange.

Competence - The quality or state of being functionally adequate or having sufficient knowledge, and/or judgment, and/or skill.

Comprehensive language assessment - This is an evaluation that assesses three major components: Comprehension, expression, and communication areas. Within these areas you would assess comprehension of single words, morphological units, syntactic structures, and connected language.

Confused-agitate - Level IV of the LOCF, characterized by bizarre behavior which is not relative to the immediate environment. No object/person discrimination , no cooperation, minimal attention ability, and no short term recall.

Conversational repair strategy - A method or technique used to repair a communication breakdown. For an AAC user this strategy may be a back-up communication system.

Coverage vocabulary - Vocabulary that is needed to communicate essential messages. It is dependent on the individual communication needs of the AAC user. It contains messages that are necessary to "cover" an individual's basic communication needs.

Developmental Apraxia of Speech (DAS) - Syndrome like disorder that occurs more often in males than females and is typically found in families with a history of speech and language problems. It may occur with other language deficits but it is not a language disorder itself, nor does it exhibit symptoms like dysarthria. People with DAS often have moderate to severe congenital articulation problems as well as vowel errors, oral nonverbal apraxia, increased errors on longer productions, and groping trial and errors during speech production. Traditional treatment methods often doesn't work for these people.

Digitized speech - A type of electronic speech that consists primarily of natural speech that has been recorded, stored, and reproduced. This type of electronic speech requires a lot of computer memory.

Directed scanning - The scanning pattern is under the control of the user. By using multiple switches the user can move the scanning indicator up, down, left, right, or diagonally directed towards a target.

Disability - Is the aspect of a disorder that is related to the reduced ability of an individual to meet their daily living needs.

Dual sensory impairment (DSI) - Refers to an abnormal function of two of the 5 receptive pathways (vision, auditory, olfactory, tactile, taste).

Early communication process (ECP) - Consists of four levels of communication- gaining attention; making requests/expressing interests; making choices/expressing preferences; use of symbols to make choices/express preferences.

Echolalia - Tendency for an individual to repeat without modification that which is spoken to them. It has been noted that individuals who are echolalic have poorer linguistic abilities, in particular poorer comprehension than those who do not echolalic and use functional speech.

Ecological inventory - A method of securing the communication and vocabulary needs of a consumer by conducting a detailed on-site analyses of communication requirements of non-disabled partners in different communication activities

Educational/regional center - Primary purpose of these centers is to train personnel, assess equipment and provide assistance with intervention and follow-up. Regional centers establish an "umbrella" agency to ensure that AAC services are provided to individuals and staff members.

Efficient system - Is a system that enables the AAC user to produce messages in an acceptable amount of time without extensive practice or training.

Emblem - Gestural behavior that can be "translated" or defined by a few words or a phrase and that can be used without speech to convey the message.

Encoding - The term used to identify any technique or strategy in which the user can use multiple signals that together specify a desired message. These strategies could include numbers, letters, and/or icons and increase the speed of message formation and transmission.

External scaffolding - External information representation and activity structure.

Extrinsic message - Involves the use of devices that result in a message different than the mode used to send it (pencil-written word).

Facilitated communication - A communication technique that assumes that the user has communicative competence rather than impairment and that the user will be able to produce meaningful, even complex messages with the proper support. The individual's forearm, wrist, and if necessary the index finger is physically supported by the facilitator.

Fixed display - A display in which the symbols or items on the board or overlay are "fixed" in a particular location.

Fringe vocabulary - Vocabulary words and messages that are unique (personal nature) to the individual. These vocabulary words are recommended by the consumer or by someone who knows the consumer's communication situations and system. This vocabulary may include names, locations, and vocabulary unique to the user.

Functional skills of communication - Are communication skills which are required to initiate and maintain daily interactions within the natural environment.

Functionality of communication - It is the level of an individual's communication and how well it fits their role in everyday life. How functional an individual's communication is measured by how demanding the communicative role is in the environment.

Gestalt processing - An inflexible mode of information processing in which stimulus input is examined in its entirety rather than in terms of its component parts. It's a holistic style of processing.

Humoral blocks - Upper arm blocks which are attached to a wheelchair or a tray which prevents the arms from going back. This positioning allows the arms to be place in more functional position for hand use.

Iconicity - Refers to the continuum that describes symbols by ease of recognition.

Impairment - Any loss or abnormality of psychological, physiological or anatomical structures or functions.

Independence (levels)

complete: no human assistance needed for student to participate
set-up: the individual receives some assistance in "system" set-up (art supplies, moving the appropriate overlay onto the device) the user can function independently within the activity.
assisted: physical or verbal assistance from classmates or teacher is required for participation

Initiations - When client spontaneously offers some interactive or communicative behavior.

Integration - The physical presence of a student with disabilities in a regular classroom setting with same-age peers.

full: attend age-appropriate classroom for the entire day
selective: attend age-appropriate classroom for some of the day. Receives instruction in other settings and/or environments for remainder of the day.
excluded: does not attend age-appropriate regular education classrooms

Intelligibility - The ability of unfamiliar listeners to comprehend messages

Interdisciplinary team - Professionals assess students individually but there is an attempt to control information fragmentation through formal communication channels.

Interrupted behavior chain - Technique used to teach requesting in natural settings. Based on milieu teaching and uses natural routines, or "behavior chains" as contexts for communication.

Intervention planing phase - A sequence of information gathering activities to determine communicative competence and consider appropriate goals and activities (record review; observations/structured interactions; interviews; identify goals and activities.

Intrinsic message - Messages that are inherent in the symbol that the communication partner sees. They are inseparable from the symbols used to produce them-what you get is what you see/hear (manual signs, spoken word).

Invented spelling - An approach in which children with a basic understanding of phonics are encouraged to write by listening to the sound units of words and associate letters to those sounds even if the word is not spelled correctly.

ISSAC - International Society for Augmentative and Alternative Communication- International organization devoted to the advancement of the field of AAC.

LCD screen -- A liquid crystal display consists of two plates of glass with liquid crystal material between them. The screen does not generate light but rather modulates it. LCD screens are the viewing screens found on many VOCAS.

Level of cognitive functioning scale (LOCF) - A system designed to facilitate classification of persons who have experienced TBI. The intent is to describe cognitive and language behaviors that occur during recovery. This scale includes the following eight levels: no response, generalized response, localized response, confused-agitated, confused, inappropriate, non agitated, confused-appropriate, automatic- appropriate, purposeful and appropriate.

Limited use policies - Students who use AAC devices in school and are not permitted to take them home after school or in some cases not permitted to take them out of the school building for community-based instruction because the device was purchased with school funds.

Linear scanning - The scanning indicator moves element by element in a linear direction across each row on the scanning display.

Linguistic competence - An adequate level of mastery of the linguistic code (the linguistic code of the language community and the linguistic code of the AAC device).

Literal comprehension task - This taps a child's ability to perform a grammatical analysis on an incoming message. The individual identifies the meaning of the lexical items and determine the syntactic relationship that exist between and among the lexical terms.

Luminance -- Refers to the brightness of the computer screen.

Managing facilitator - Coordinates primary areas of responsibilities such as linguistic or operational competence. It would include leading AAC team to consensus about intervention roles, scheduling intervention activities, clarifying the roles of other facilitators and documenting progress.

Memorabilia box - A box filled with personal items that remind the user of personal events. It can be used to encourage meaningful conversation and as a memory aid to reduce the "quizzing approach". It helps in focusing the attention of the user, directing conversations, and reducing frustration behavior.

Message prediction - A dynamic retrieval process in which options offered to the AAC user change based on the portion of the message that has already been formulated.

Metalinguistics -- This is language awareness, or the ability to think about language ability and to focus on language as an object that has its own existence.

Miniboards - A pictorial or graphic symbol display that can be used as overlays on electronic devices or as stand-alone low tech communication aids. They allows the child to participate in special events and regular activities by ensuring that needed vocabulary items are available.

Minspeak - A registered trademark of Semantic Compaction Systems is a type of visual language in AAC. It is a pictorial system that allows for fast and accurate access to language through a process of using multiple meaning icons.

Multiple primary interactants - Current AAC literature underscores the need for multiple interactants ( caregivers, teachers, public school para professionals, nursing home staff, job coach, etc.) in AAC service delivery. This entails the interactants having a working knowledge of the individual's AAC system (high and low tech systems).

Multiple Sclerosis (MS) - MS is a degenerative disease of the white matter of the central nervous system and causes destruction of the myelin sheath.

Muscular Dystrophy - A primary motor impairment characterized by progressive muscle weakness. The most common form, Duchenne dystrophy is a hereditary disease that affects 1 in every 3,500 males. The disease manifests itself generally during the ages of 2-6 years. Heart or respiratory failure usually results in death during adolescence or young adulthood.

Natural language teaching - A method language instruction which employs the child's voluntary engagement with an object as the purpose of object labeling. Any clear verbal response by the child is reinforced and shaped. Praise and the continued opportunity to play with the target object and continued interaction with the object is used as the reinforce.

Neck collar - A head support for individuals in wheelchairs that keeps the head centered in midline and also prevents it from falling too far back or to the side. The goal of the collar is to position the head so the face is perpendicular to the floor and is in midline. Correct positioning is critical for the functions of breathing, vision, feeding and attention.

Nonrelational words - Words that have referents in the real world such as chair, dog, shirt, etc.

Nonrepresentational reference - Part of the Movement-Based Approach that is based on the principle of "learning through doing." This segment involves teaching the individual to identify body parts on three-dimensional and two-dimensional models. These activities develop body image, teach pointing, and encourage the individual to be independent from the facilitator.

Numeric encoding - A number code is used to represent an entire message or it could also represent an individual word. The relation of the code and the message is arbitrary.

Nurturance - One of six levels of the Movement-Based Approach in which the goal is to develop a warm, positive relationship between the individual with disabilities and the facilitator. It promotes interest in communication interactions and enhances a willingness to participate in social exchanges.

Ocular mobility - Functioning of the eye muscles that enable the eyes to move together smoothly in all directions.

Opportunity barriers - Barriers that are imposed by person other than the individual with the severe communication disorder and cannot be eliminated simply by providing an AAC system or intervention. The opportunity barrier is blocking the individual from participating.

Opportunity strand - The person with disabilities must be allowed the opportunity to participate once access issues have been resolved.

Orientation of display - Orientation or position of the display relative to the floor.

Osteogenesis Imperfecta - A group of connective tissue disorders that are hereditary and result in fragile bones (also known as the "brittle bone disease") While these individuals do not experience concomitant cognitive or language impairments, they frequently require alternative access for written communication, due to the difficulties they have with writing due to frequent fractures.

Palm writing - Message sender spells out messages by using his or her index finger to draw the letters of the alphabet in the palm of the message receiver' hand.

Parkinson's disease - A syndrome composed of a cluster of motor symptoms that include tremors at rest, rigidity, paucity (reduction in movement) and impaired postural reflexes. It results from a loss of dopaminergic neurons in the basal ganglia and the brainstem.

Picture schedule system - A vertical display of each days activities, with each activity represented by a separate card fastened to the schedule by a paper clip.

Play - Is an intrinsic activity that is done for its own sake rather than as a means to achieving any specific end. It is spontaneous and voluntary undertaken by choice rather than by compulsion. It enjoys an element of enjoyment, something that is done for fun.

Positioning - Positioning is a process that involves arranging an person's posture to best facilitate motor functioning which has a direct impact on the accuracy, speed, ease of the person's movements.

Practice barriers - Procedures that have become common place within a family, school, or workplace, but are not actual policies (ex. school district restricting district funds for AAC devices that are used outside the school setting).

Pragmatics - Language development skills in the context and environment that include such factors as strategies for topic setting, strategies for clarification and repair, and strategies for decision making about when to use which communication modality. Pragmatic consideration enables more effective communication interactions.

Preset scanning - Process in which the scanning indicator moves in a predetermined, predictable pattern controlled by the electronic scanning device. Patterns of scanning may be either linear, circular, row-column or block.

Rate enhancement - Strategies that enhance or increase the rate of communication output of the user and therefore enhances the communication efficiency.

Reactive behaviors - Refers to such communication behaviors as movements, crying, gurgling. Children with DSI reactive behaviors are unintended, are largely involuntary. The learner has little awareness or understanding of the social bases or context in which the behaviors are elicited.

Rebus - A picture that visually or nominally represents a word or a syllable. For example, a rebus of a knot could be used to symbolize either "knot" or "not".

Regional AAC center - Primary purpose for these centers is to conduct AAC evaluations and make recommendations for intervention and/or equipment. Staff member are well trained and experienced in the area of AAC and the "Centers" are well equipped with AAC equipment. Services are obtained through self-referral by potential AAC users or their families, or by educational, social services, vocational, and/or medical personnel or agencies.

Regulators - Nonverbal behaviors that maintain and regulate conversational speaking and listening between two or more people.

Relational words - Words which do not have a real-world referent (e.g., in/out, hot/cold).

Remnant book - A topic setting approach that provides a way for a beginning symbol user with limited verbal output to tell people about past events, such as those that occurred during the day at school or at home etc.

Resonance activities - Rhythmic movements that the individual and the facilitator perform while in direct physical contact. Designed to shift the individual's attention from self to the external world of people and objects. For example, hand on hand prompt to assist the individual to wipe a tabletop with a sponge.

Role extension - Refers to an increase in a professional's knowledge of other professional fields and the incorporation of this knowledge into their own field.

Role release - This occurs when professionals release their traditional roles, so that all members of the team can work in a more holistic fashion.

Routines - Designed to provide scaffolding to assist in overcoming receptive language difficulties.

Sacral setting - A sitting position in which the lower back is rounded and the upper trunk is usually flexed due to the pelvis being tilted posteriorly.

Salient letter encoding - An encoding technique that employs the use of the initial letter of the key words to formulate the code. Also referred to as logical letter coding (LOLEC).

Scaffolding - External information representation and activity structure which helps to maximize participation in conversational and writing activities.

Scan mode - The manner in which the switch interfaces operates in conjunction with the scanning device to achieve the scanning process

Scanning - an indirect method of accessing a computer or a voice-output device. It requires an individual to activate a switch and make a succession of choices that leads to the desired input. These choices are usually made via a switch or switches, some other type of keyboard emulator or voice.

Selective integration - a student is integrated into the regular classroom during only special classroom activities while remedial instruction is in other curricular activities. Therapy may be provided during nonacademic classroom activities.

Severe disabilities - Individuals of all ages who require extensive ongoing support in more than one major life activities in order to participate in integrated community settings and to enjoy a quality of life that is available to citizens with no or fewer disabilities.

Sigsymbols - A symbol set which combines black and white line drawings and drawings of manual signs.

Sincere message or information message - Partner should ask questions of the patient because they truly want to know the answer.

Single letter prediction - To facilitate rate enhancement, a probability-based strategy on the probability of another letter occurring after a certain letter or combination of letters. In the combination of "in" there is a higher probability of "g" following in the English language.

Sling set - The type of seat often found on a wheelchair. This type of seat encourages asymmetrical posture and does not provide sufficient stability. It may also cause internal rotation of the hips.

Social competence - Is the knowledge, judgment, and skill in the social rules of communication, including both the sociolinguistic aspects (pragmatics) and the sociorelational aspects.

Social participation (levels)

competitive: student actively contributes to group dynamics and social activities with peers.
active: student may decide which groups or activities to attend but do not influence group or interactions.
involved: same as active but, participation in outside of class activities is reduced. Instead, more emphasis is placed on family-centered activities.

Spatial information - Concrete, permanent, and predictable units of meaning, presented holistically, and resulting in a more stable time relationship for processing (i.e., line drawings, pictures, etc.).

Specific Language Impairment (SLI) - A primary language disorder also known as developmental aphasia, dysphasia, childhood aphasia, and language disability. It is thought to be a disorder of language expression, comprehension, or both and demonstrated by uneven language development, poor auditory processing skills, short auditory memory, disordered temporal sequencing, and repetition of auditory patterns.

Specific-need communicator - Individuals who may need support in situations that require more than the usual amount of specificity, clarity, or efficiency in communicating. For example, talking on the phone, placing bets at the racetrack, and writing memos.

Speech synthesis - Is a type of voice output communication which replicates natural speech through an electronic output process

Spinal ALS - A form of ALS which refers to predominant involvement of the spine. these individuals may return normal to mildly dysarthric speech for a considerable period of time, even as they experience extensive motor impairments in their trunk and limbs. For these individuals, the need for an augmented writing system often precedes the need for a conversational system.

Step scanning - This scanning techniques allows the user to advance one step at a time for each activation of the switch. There is a one-to-one correspondence between cursor movement and switch activation.

Strabismus - An oculomotor functioning impairment that prevents an individual from maintaining proper eye position. This is caused by weak eye muscles that allow the eyes to stray from the binocular fixation position in a converging or diverging manner.

Strategic competence - The use of strategies that allow people with communicative difficulties to effectively utilize different strategies for various communicative situations.

Structured guidance - Provided by the skilled partner and allows performance at language and cognitive levels of which child would not otherwise be capable through teaching techniques.

Sub clinical aphasia - Linguistic processing deficits demonstrated during evaluation which are not demonstrated by clinical manifestation of linguistic impairment.

Sundowning - Behavioral phenomena displayed by persons with Alzheimer's disease in which there is greater confusion , restlessness, and insecurity demonstrated late in the day, especially after dark.

Supplemented speech - Supplemented speech is a strategy used with dysarthric speakers to improve their intelligibility. An alphabet board or other AAC device is used to allow the speaker to indicate the first letter of each word as he says it. Those that receive the message are then able to narrow down the range of possibilities and intelligibility is increased while still allowing for natural speech.

Switch control - There are six components to assess for switch control:

Wait: the ability to wait until the appropriate time
Activation: the closing of the switch
Holding: maintaining contact with the switch to hold it closed or activated
Release: lifting the contact with the switch as to open it and stop activation
Reactivation: closing the switch again or activating which would require going through the previous steps.

Symbols - Something that stands or represents something else. The symbol could use visual, auditory, and/or tactile representation of conventional concepts (gestures, photos, manual signs, picto-ideographs, printed words, objects, spoken words, Braille).

Synthesized speech output - Pre-recorded verbal information that is produced by an electronic device when symbols are selected by the user to activate and create messages.

Technique - A method of transmitting messages (linear scanning, row-column scanning, encoding, signing, and natural gestures, etc.)

Temporal information - Abstract units of meaning that are presented sequentially, resulting in processing of information which is transient in nature and fades over time, i.e., spoken language.

Text-to-speech - A method of producing synthesized speech. Messages are entered into the VOCA using orthographic symbols and "translated" electronically into speech output.

Three-point eye referencing - A skill used by the AAC user when using an eye gaze system. The user initiates communication by looking at her/his communication partner, then eye gazes to the chosen picture symbol and re-establishes eye contact with the partner to complete the communication.

Timed activation - Is associated with direct selection. Time activation is a strategy which requires the AAC user to identify an item on the display through physical contact or by shining a light beam and by sustaining this contact for a determined period of time in order for the selection to be recognized by the device.

Topic board - A display on a communication board that designates which topic the speaker has chosen. It is similar to an alphabet board because it provides the listener with a cue, in this case the cue references the topic.

Topic identification - An AAC technique that may be used if a person's speech is marginally intelligible, his or her message can often be understood if the listener is aware of the semantic context of topic.

Topic setter cards - Cards or notes with simple drawings or symbols that pertain to the child's interests. They may be used with collections, remnant books or other topic setting techniques.

Total communication paradigm - Is where the communication partner accompanies each picture or sign with the corresponding spoken word (aided language stimulation).

Transdisciplinary team - Involves the transfer of information, knowledge, or skill across discipline boundaries. This is done in an attempt to make direct service providers proficient across different specialties. Assessment is often completed through the collaborative efforts of all team members.

Unaided techniques - Symbols that require no external device or item for the production of communication (gestures, signs).

Universal cuff - An assistive device that allows an individual with limited hand function to access a keyboard with greater effectiveness.

Usher's syndrome - A dual sensory impairment condition characterized by hearing loss at birth and progressive visual loss from retinitis pigmentosa beginning by age 10. This is a genetic condition that accounts for over 50% of the dual sensory impairment cases in the United States.

USSAAC - United States Society for Augmentative and Alternative Communication- A national organization devoted to the advancement of the field of AAC.

Verbal stereotypy - Abnormal repetition of a phrase.

Visual acuity - The clarity of vision, allows an individual to discriminate details.

Visual disability - Functional limitations that may result from the visual impairment and how impairment affects an individual's lifestyle.

Visual field - Refers to the area in which objects are visible to the eye without a shift in gaze. This normally extends in an arc of 150 degrees from right to left and 120 degrees up and down.

Visual impairment - A generic term which refers to a wide range of visual problems. These problems can range from mild interfaces of the visual system to total blindness.

VOCA - Voice output communication aid- Electronic devices which provide individuals who can not meet their daily communication needs with the capabilities of having voice output.

Vocabulary selection - The process of choosing a list of appropriate words or phrases or events (stories) from a pool of communication possibilities.

WISSAC - Wisconsin Society for Augmentative and Alternative Communication- A State organization devoted to the advancement of the field of AAC.

Written choice conversation - Technique in which a person answers open-ended questions by pointing to written choices generated by communication partners. Partners provide a short list of appropriate responses to their questions and says the written choices and the person points to the word representing their response or choice.

Zero-rejection model of AAC - Any severely speech-impaired person is a potential candidate for AAC regardless of prerequisites skill status.

Zone of proximal development - Involves the difference between the child's actual level of development as determined by independent performance and the child's potential level of development accomplished through collaborative interaction with the more skilled partner.