Glossary of Terms Disabled Human User of Assistive Technologies

Glossary of Terms	Definitions	Examples
Abandonment	Abandonment of a device can be attributed to an individual who is depressed, angry, embarrassed to use the device, withdrawn, or resistant; has low self-esteem or poor socialization and coping skills; or lack the skills and or training to use the device.	Being aware of the psychological factors that affect assistive technology use can facilitate the matching process for the ATP and optimize use of assistive technology.
Apraxia	Is the inability to execute learned purposeful movements, despite having the desire and the physical capacity to perform the movements.	Apraxia is an acquired disorder of motor planning, but is not caused by incoordination, sensory loss, or failure to comprehend simple commands (which can be tested by asking the person to recognize the correct movement from a series).
Central Processing	Is the Human functions of perception, cognition, neuromuscular control and psychological factors.	Motor planning is used to describe the process by which purposeful movements are executed to accomplish a purposeful task.
Cognition	The process of understanding and knowing which involves the skills of attention, memory, problem solving, decision making, learning, language, and other related tasks.	The use of a powered wheelchair requires several types of cognitive function. The human operator must visually scan the environment, process the sensory data, make decisions as to the direction of movement desired, and activate the corresponding effector to cause the motion of the wheelchair in the desired direction.
Development	The combination of growth and learning leading to changes in a child.	The work of Jean Piaget is particularly useful because its emphasis on object manipulation in the early years and the consideration of alternative methods of problem solving as the child grows into an adult.
Effectors	The neutral, muscular, and skeletal elements of the human body that provide movement or motor input.	Powered wheelchairs typically employ joystick control activated by hand movements, and hand and finger movements for keyboard use.
Engram	A preprogrammed pattern of muscular activity represented centrally.	They develop when there are many repetitions of a specific movement or activity. With repeated, consistent movement, the conscious effort of the person is reduced and the movements become more automatic.
Growth	Changes that occur in a child as a result of physical development of the central nervous system.	Development is a function of growth.
Intrinsic Enablers	General underlying abilities that individuals use to perform activities and tasks.	Inputs from sensors is necessary for obtaining data from the environment, and limitations can arise in both the sensitivity and range able variation in size, amplitude, or magnitude of the sensory.
Learning	Changes that occur in a person because of contact with some environmental influence.	Development is a function of learning.
Memory	Often considered to have three components: sensory memory, (2) short-term memory, and (3) long-term memory, each playing a role in assistive technology.	Somatosensory long-term memory plays a role in many aspects of assistive technology application. Tactile memory is also important in seating and positioning systems.
Morphology	The rules for organizing the smallest meaningful units of language, called morphemes.	Words are articulated sounds or series of sounds that are used alone as units of language and symbolize, communicate and have no meaning.
Motivation	Any influence that give rise to performance.	Motivation may result from the human, activity, context, or assistive technology components of the system.
Motor control	The result of the integration of sensory, perceptual, and cognitive components into a motor pattern that is executed by the effectors.	In order to control task, the human operator must be able to locate a target, plan a movement to that target, and produce a desired action once the target is reached.
Muscle Tone	The resistance to stretch provided by neural activity, viscoelastic properties of muscle and joints, and sensory feedback to the CNS.	Muscle tone is high enough so that the individual can resist gravity and low enough to allow movement. Tone varies with age, level of activity, stress, and other factors. Muscle tone in infants is generally decreased, or hypotonic, and they begin to develop more normal tone as their nervous system develops.
Optimal Use	The use of an assistive technology that is the greatest possible given the user’s skills.	It is predicted that those individuals who are unmotivated; intimidated by technology; embarrassed to use the device; impatient or impulsive; or have low self-esteem, unrealistic expectations, or limitations in the skills needed may become partial.
Paralysis	Significantly reduced (or absent) muscle strength preventing the use of certain effectors; muscle weakness caused by partial paralysis that make it difficult to move but does not prevent movement is called paresis.	An adapted door handle could be used to require less force to be applied in order to turn the doorknob.
Perception	The interpretation and assignment of meaning to data received from biological sensors; involves an interaction between information derived from sensed data and information stored in memory based on previous sensory experience.	It is a combination and interpretation of data from all our sensory systems that provide a meaningful picture of the environment and our interaction with it.
Phonology	The sounds used in any particular language and the rules for their organization.	To produce English speech using an electronic speech synthesizer.
Pragmatics	The relationship between language and language users.	By understanding the rules of pragmatics, a user of language is able to observe social conventions.
Primitive Reflexes	Characterized by immediate and automatic movement performed at a subconscious level, usually imitated by sensory stimulation.	They are usually initiated by sensory stimulation. Present at birth or shortly thereafter, these reflexes are inhibited or integrated into volitional movement patterns as the infant develops.
Psychosocial Function	Consists of self-identity, self-protection, and motivation.	These factors are related to the person’s acceptance of a disability, the approach a person takes to the assistive technology, and the ultimate effectiveness of the assistive technology for the person.
Range	Maximal extent movement of an effector.	The use of push rims on a manual wheelchair requires a relatively large range of movement, whereas the use as a computer mouse requires a relatively small range.
Recall	The type of memory that relies exclusively on the person’s abilities to retrieve information with no assistance.	The task of recalling information relies exclusively on the person’s abilities, with no assistance from the system.
Recognition	The type of memory that requires the person to identify the proper or desired item from a list.	List or identify
Reluctant Users	Individuals who are unmotivated, intimidated by technology, embarrassed to use the device, impatient or impulsive, have low self-esteem, unrealistic expectations, or limitations in the AT skills needed.	Characteristics of the person who avoids using a device may include someone who does not have the skills to use the device and someone who is depressed, unmotivated, embarrassed to use the device, uncooperative, withdrawn, or intimidated by technology.
Resolution	The smallest separation between two objects that the effector can reliably control.	The spacing of individual keys on a keyboard requires relatively fine motor control and an effector with good resolution.
Semantics	The relationship between words and their meaning.	The word gold may mean the color, the metal, or the concept of wealth.
Sensors	Intrinsic enablers that obtain data from the environment; characterized by sensitivity and range.	Reading and mobility systems for the visually impaired and hearing aids for individuals with auditory impairment are designed to compensate for these specific loses.
Spasticity	Increased muscle tone; also referred to as hypertonicity.	Several types of disorders can result in spasticity. Increased muscle tone is often accompanied by exaggerated reflexes and imbalances between antagonist muscle pairs controlling joints.
Syntax	The rules for organizing words into meaningful utterances.	Various grammatical rules are used by linguistics to describe language usage and by designers of argumentative communication systems to enhance communicative ability.
Visual Accommodation	The process by which the ciliary muscles change the curvature of the lens and hence the focal point of the eye.	If a person is using a keyboard device with a visual display, the separation of these two system components may require constant accommodation as visual gaze is directed at the keyboard and then at the display and back to the keyboard.