Glossary of General Terms

Adapted materials: visual aids and materials specially designed or modified for individuals with a visual impairment.
 
Articulation: the production of individual sounds in connected speech.
 
Assistive technology: products, devices or equipment, whether acquired commercially, modified or customized, that are used to maintain, increase or improve the functional capabilities of individuals with disabilities.
 
Babble: the meaningless repetition of consonant-vowel combinations for entertainment.
 
Behavioral objectives: a statement of measurable and observable behavior a student will display at the end of instruction.
 
Bilateral: relating to the two sides of the body.
 
Braille: a tactile system made up of one to six raised dots used by individuals who are blind to read and write -- the specific arrangement of dots denotes various letters and symbols.
 
Close circuit television (CCTV): a video system which magnifies an image through a monitor for reading, writing, typing, and large print computer access.
 
Co-active movement: to act in unison. To manually manipulate the child through an activity so the child may develop a kinesthetic image of the activity.
 
Copy: after the child is shown a model, they are asked to draw one like it, without a demonstration.
 
Crawl: to move using hands and knees with the child's stomach off the floor.
 
Creep: to move using hands and knees with the child's stomach resting on the floor.
 
Criterion-referenced test: test designed to provide information on the specific knowledge or skills closely related to instructional content. A test is said to be criterion-referenced when provision is made for translating the test score into a statement about the behavior to be expected of a person with that score.
 
Developmental Domains: Term used by professionals to describe areas of a child's development, for example: "gross motor development" (large muscle movement and control); "fine motor development" (hand and finger skills, and hand-eye coordination); speech and language/communication; the child's relationship to toys and other objects, to people and to the larger world around them; and the child's emotions and feeling states, coping behavior and self-help skills.
 
Developmental milestones: Term frequently used to describe a memorable accomplishment on the part of a baby or young child -- for example, rolling over, sitting up without support, crawling, pointing to get an adult's attention, walking.
 
Early intervention: Refers to the range of services designed to enhance the development of infants and toddlers with disabilities or at risk of developmental delay. These services should be offered, to the maximum extent possible, in a natural environment, such as the home or in community settings, in which children without disabilities participate. Early intervention services that are under public supervision, must be given by qualified personnel and require the development of an individualized family service plan (IFSP), developed in conjunction with the family, to guide the early intervention or therapeutic services given to a child.
 
Eligibility: Specific criteria of developmental delay that meets the eligibility level needed for publicly funded services. This criteria is unique to each state's definition. Children who have a diagnosed physical or mental condition or are experiencing developmental delays are "eligible" for services.
 
Etiology: The cause or origin of a disabling condition.
 
Expansion: the rephrasing of a child's utterance into a more complex model.
 
Expressive language: conveying thought through gestures, signing, talking, and writing.
 
Extension: straightening out all or part of the body.
 
Flexion: bending the body at the joints.
 
Guided Hand Technique: as opposed to the older term "hand over hand", guided hand technique is accomplished by having the child's hand on top of yours and moving your hand with the child's freely following. This technique allows for choice on the student's part and does not physically force the child's hand to move.
 
Guided Travel Technique: the technique wherein a person who is sighted guides a person who is visually impaired in an unfamiliar area. This technique needs to be taught, as it is important that it be done correctly.
 
Hypertonic: the condition of having too much muscle tone causing difficulty moving into positions.
 
Hypotonic: the condition of having too little muscle tone creating difficulty maintaining positions.
 
IDEA: An acronym for the Individuals with Disabilities Education Act which provides grants to states and jurisdictions to support the planning of service systems and the delivery of services, including evaluation and assessment, for young children who have or are at risk of developmental delays/disabilities or a specific sensory loss. Funds are provided through the Infants and Toddlers Program (known as part C of IDEA) for services to children birth through 2 years of age, and through the Preschool Program (known as Part B-Section 619 of IDEA) for services to children 3 through 5 years of age.

IFSP: A statement of the family's strengths and needs related to enhancing the development of the family's child, including specific statements about outcomes, criteria, and timelines regarding progress, specific services, provisions for service coordination, and dates for initiation, duration and reevaluation process.

Imitate: to repeat an observed behavior. After the child is given a demonstration on how to complete an activity, they are asked to imitate (copy) it.
 
Imaginary play: fanciful or make-believe play wherein the child plays with real objects in a made-up fashion. Toy blocks may become a boat, pots and pans a drum set.
 
Inclusion: the practice of integrating children with a disability with peers with no disability to the maximum extent possible.
 
Independent Play: similar to solitary play wherein the child plays predominantly by himself, constructing play routines that are individual in nature.
 
Inflection: the change in the pitch used in speech to add meaning.
 
Inhibition: the suppression of patterns of movement (reflex muscle contractions) that interfere with normal activity.
 
Intelligibility: the capability of being understood by those other than immediate caregivers.
 
Intonation: the change in volume or quality of voice used in speech to add meaning.
 
Jargon: meaningless syllables with inflection patterns.
 
Kinesthesia: the sense that detects body position, weight, or movement of the muscles, tendons, and joints.
 
Midline: the imaginary line drawn through the center of the body dividing it into left and right sides.
 
Mobility: the ability to move from place to place safely and efficiently in and around the environment using all senses, including residual vision.
 
Model: to provide an example for the child to imitate.
 
Motivation: a rewarding object or activity used to encourage a child to increase a certain behavior or activity.
 
Multi-disciplinary team:  A group of people with different kinds of training and experience working together, usually on an ongoing basis. Professionals often use the word "discipline" to mean a "field of study," such as medicine, social work, or education; therefore, a multidisciplinary team might include a pediatrician, an occupational therapist, a social worker, a vision specialist, and an early childhood educator.
 
Nemeth code: a Braille numerical System which allows users to read and write Braille numerals and `mathematical computations.
 
Norm referenced test: A norm-referenced test is a type of test, assessment, or evaluation in which the tested individual is compared to a sample of his or her peers (referred to as a "normative sample"). The term "normative assessment" refers to the process of comparing one test-taker to his or her peers.
 
Object concept: the recognition, use, and classification of objects.
 
Object permanence: the understanding that an object continues to exist after it is out of sight, hearing, or touch.
 
Occupational Therapist (OT): A professional who has specialized training in helping an individual develop mental or physical skills that aid in daily living activities, with careful attention to enhancing fine motor skills (hand and finger skills, eye-hand coordination and sensory integration). In a developmental assessment, the occupational therapist would assess the child's fine motor skills, coordination, and age-appropriate self-help skills (eating with utensils, dressing, etc.). She would also look at how the child responds to and uses what he sees, hears, feels, tastes and smells.
 
Orientation: the ability of a student who is visually impaired to know and understand where they are in their environment by recognizing their surroundings and objects in relation to themselves.
 
Orientation and mobility specialist: a person who instructs children who are visually impaired how to familiarize themselves to new surrounding and to travel safely and independently indoors and outdoors.
 
Parallel play: play that is usually associated with toddlers, although it happens in any age group. Children play side by side with similar toys, but there is a lack of group involvement.
 
Passive: accepting without resistance the movement or action on a person's body.
 
Perseverative behaviors: behaviors or mannerisms that are repeated or persist in specific patterns of movement or actions.
 
Physical Therapist (PT): A professional trained in assessing and providing therapy to treat gross motor delays, disease and injury using methods such as exercise and range of motion. In a developmental assessment, the physical therapist would assess the ability and quality of the child's use of her legs, arms, and complete body by encouraging the display of specific motor tasks as well as observing the child in play
 
Prerequisite skill: skills a student must demonstrate before the next phase of learning can be initiated.
 
Prescriptive program: a systematic method of teaching and evaluating a particular skill in which the skill is broken down into small increments.
 
Primary caregiver: the adult who cares for and is best known to the child.
 
Prolonged regard: looking at a fixed object for 4-5 seconds.
 
Pronation: the rotation of the hand, wrist, or forearm so the palm faces downward.
 
Prone: Lying on the stomach.
 
Protective extension: a reaction to the sudden movement of the body in which arms, and/or legs are extended to try and protect oneself from a fall.
 
Radial: associated with the thumb side of the hand and forearm.
 
Receptive language: the ability to understand what is being communicated usually through verbal language.
 
Reciprocal: alternating the movement of an arm or a leg.
Referral: The process of helping a child or family to access a service -- for example, a more in-depth assessment, or an organization that provides child care or early intervention.
Reinforcement: any action that increases the probability that a given behavior will occur again.
 
Reverse chain: to teach the last step of a task first by co-acting the first steps with the child and allowing them to complete the last step independently.
 
Solitary play: The child plays alone with toys that are different from those chosen by other children in the area. Solitary play begins in infancy and is common in toddlers because of their limited social, cognitive, and physical skills. However, it is important for all age groups to have some time to play by themselves.
 
Standardized test: test designed to sample individual performance, administered according to prescribed directions, scored with definite guidelines, and interpreted in reference to certain normative data.
 
Stimulation: any external events that provoke a response by an individual.
 
Successive approximations: sequential behavior that is closer to the described behavior with each attempt.
 
Supination: turning the forearm so the palm is facing upward.
 
Supine: lying on the back.
 
Symmetrical movements: moving corresponding body parts simultaneously and in the same direction.
 
Tactually defensive: resistance to or avoidance of touching or handling various objects.
 
Trailing: a method by which a person who is blind or visually impaired follows a wall with arm outstretched and back of hand on the wall.
 
Transition: the move from one type of service to another. Transition from early intervention to early childhood education services; transition from early childhood to school age services, etc. Brought about more by age changes and resulting more in paperwork changes than level or amount of services.
 
Unilateral: affecting or occurring on only one side of the body.
 
Verbalize: to express a thought or idea in words.
 
Vision Specialist: a teacher who offers specialized instruction to meet the unique needs of a child who is visually impaired. These teachers are also called teachers of visually impaired, vision teachers or vision instructors.
 
Vocalize: to produce consonant or vowel speech sounds or to use words.
 

 

Glossary of Visual Terms 

20/20: the expression for normal eyesight. The first number refers to the distance from the test chart, which is usually 20 feet. The second number denotes the distance at which a person with normal eyesight could read the line with the smallest letters that you could correctly read. If your visual acuity is 20/100 that means that the line you correctly read at 20 feet could be read by a person without a visual impairment at 100 feet.
 
Accommodation: the adjustment of the lens to see objects at various distances by changing its power and focus to produce a clear image on the retina.
 
Acuity: clearness of eyesight. Depends on the sharpness of images and the sensitivity of nerve elements in the retina.
 
Albinism: a hereditary deficiency of pigmentation typically resulting in decreased visual acuity, nystagmus, and photophobia.
 
Amblyopia: reduced visual acuity in one eye due to cortical suppression (the brain suppressing) of unequal and therefore confusing visual images; commonly caused by unequal refractive errors, strabismus, or corneal/lens opacities.
 
Aphakia: absence of the lens due to surgical removal or congenital abnormality.
 
Astigmatism: defective curvature of the refractive surfaces of the eye since light rays are not sharply focused on the retina.
 
At risk conditions: circumstances which increase the possibility of developing associated disabilities. The following are conditions where visual impairment is often a secondary disability -- Cerebral Palsy; CHARGE Syndrome (Coloboma, heart defect, Atresia Choane, retarded physical growth, Genital Hypoplasia, ear anomalies and/or deafness); CMV (Cytomega­lovirus); DeMorsier's Syndrome; Encephalitis; Hydrocephalus: Rubella; Tuberous Sclero­sis.
 
Bifocal Glasses: used to correct vision at two distances, composed of two ophthalmic lenses such as a plus lens for near vision and a minus lens for distance vision.
 
Binocular vision: the ability to use the two eyes simultaneously to focus on an object allow­ing for correct interpretation of the object's position in space.
 
Cataract: an opacity of the crystalline lens resulting in decreased visual acuity.
 
CF: used by eye specialists to indicate "counts fingers," meaning visual acuity is low.
 
Coloboma: an irregularly shaped pupil or iris caused by faulty closure during prenatal development typically resulting in decreased visual acuity, nystagmus, reduced visual fields, and strabismus.
 
Color Vision Deficiency: also known as Colorblindness. It is the absence of or defect in the perception of colors. Color vision is based on perception of red, green, and blue. If there is a defect in the perception of one of these colors, a color will be perceived as if it were composed only of the other two colors. Based on the color or colors for which there is defective perception, a person may suffer from red, green, or blue blindness. Color blindness in which all colors are perceived as gray is termed monochromasia. For people with the common, inherited, types of color deficiency there is no cure.
 
Cones: light-sensitive receptors present in the retina that are sensitive to fine detail and color vision.
 
Conjunctivitis: an inflammation of the conjunctiva, the transparent layer covering the inner eyelid and the white portion (sclera) of the eyeball. Conjunctivitis can be caused by a virus, bacteria, or fungus (infectious conjunctivitis, or "pink eye", may be contagious); by allergies to pollen, fabrics, animals, or cosmetics (allergic conjunctivitis); or by air pollution or noxious fumes such as swimming pool chorine (chemical conjunctivitis). Symptoms include red or watery eyes, blurred vision, inflamed inner eyelids, scratchiness in the eyes, or (with infectious conjunctivitis) a puss-like or watery discharge and matted eyelids. Conjunctivitis is usually treated with antibiotic eye drops and/or ointment.
 
Cornea: the clear, curved covering on the front of the eye.
 
Corneal opacity: a cloudy area on the cornea (clear surface) of the eyeball.
 
Cortical Vision Impairment: the brain's inability to perceive or decode visual images as a result of an injury to the visual cortex area of the brain; the eyes are anatomically and structurally intact.
 
Depth perception: the blending of two slightly dissimilar images from the two eyes to form one image with the ability to perceive the dimension of objects and their position in space.
 
Diplopia: double vision.
 
Dislocated lens: hereditary dislocation of the lens that may be partial or complete; usual­ly bilateral and associated with other disorders.
 
Distance vision: the measure of visual acuity at a distance of 20 feet (6 metres).
 
Divergence:  refers to eyes that simultaneously rotate outward (away from each other), usually in an effort to maintain single binocular vision
 
Dominant Eye: the eye that "leads" its partner during eye movements. Humans also have dominant hand, foot, eye, and side of the brain (not necessarily all on the same side).
 
Enucleation: the surgical removal of the eyeball.
 
Esophoria: a tendency of the eye to turn inward.
 
Esotropia: observable turning in of one or both eyes.
 
Exophoria: a tendency of the eye to turn outward.
 
Exotropia: observable turning outward of one or both eyes.
 
Eye Hand Coordination: the ability of our eyes to guide our hands, also called visual motor integration.
 
Eye Tracking: the ability of the eyes to smoothly and effortlessly follow a moving target.
 
Field loss: the reduction in the size of the normal field of vision; maybe indicated by notic­ing objects to the sides, but not centrally, or noticing objects in front, but not to the sides or up and down.
 
Field of vision: the area from side to side (degrees) or up and down (degrees) which can be seen without shifting head or eyes.
 
Figure-Ground: the ability to recognize distinct shapes from their background, such as objects in a picture, or letters on a chalkboard.
 
Fixation: directing the eye to an object so its image centers on the fovea.
 
Fovea: a small area on the retina responsible for central and color vision.
 
Functional vision: the ability to use any residual vision to plan or accomplish an activity.
 
Fusion: the union of images from each eye into a single image.  There are three degrees of fusion. 1st degree fusion is the superimposition of two dissimilar targets. 2nd degree fusion is flat fusion with a two-dimensional target. 3rd degree fusion is depth perception (stereopsis) with a three-dimensional target.
 
Glaucoma: a disease characterized by an increase in the intraocular pressure where the production of fluids within the eye exceeds the drainage. If untreated can cause blindness.
 
Hemianopsia: decreased visual acuity in half of the visual field in each eye.
 
Hyperopia: farsightedness; a condition in which the light rays are focused behind rather than on the retina.
 
Iris: the colored circular membrane that controls the size of the pupil.
 
Legal blindness: a visual acuity of less than 20/200 in the better eye after correction; or a visual field limited to 20 degrees or less.
 
Light adaptation: the ability of the eye to adjust to various amount of light.
 
LP: a notation used by eye specialists to indicate "light perception" or the ability to distin­guish light from dark.
 
LPP: a notation used by eye specialists to indicate light projection or the ability to perceive and localize light.
 
Low vision: the range from mild to severe vision loss.
 
Macula: the area at the center of the retina that surrounds the fovea and is responsible for clearest central vision.
 
Microphthalmus: abnormal smallness of one or both eyes generally resulting in decreased visual acuity.
 
Minus (-) Lens: concave lens, stimulates focusing and diverges light. The lens is thinner in the center than the edges. It is used in glasses or contact lenses for people who are nearsighted (myopia).
 
Myopia: nearsightedness; a condition in which the light rays are focused in front of rather than on the retina.
 
Near vision: the measure of visual acuity at a reading distance of 14-16 inches.
 
NLP: a notation used by eye specialists to indicate "no light perception" or the inability to distinguish light from dark.
 
Nystagmus: involuntary, rapid eye movements which may be vertical, horizontal, or circu­lar.
 
Ocular Motor (OM):general eye movement ability, which include pursuits (to visually track and/or follow moving objects) and saccades (to direct and coordinate eye movement as the eye quickly and voluntarily shift from one target to another).
 
Ocularist: an eye care professional who specializes in the fitting and making of prosthetic eyes.
 
OD: a notation used by eye specialists to designate the right eye.
 
Ophthalmologist: a medical doctor who specializes in the diagnoses and treatment of diseases of the eye; this may also include prescribing eyeglasses and contact lenses.
 
Optic atrophy: dysfunction of the optic nerve generally resulting in decreased visual acuity.
 
Optic nerve: the nerve beginning at the retina that carries information of the retina to the brain.
 
Optician: an eye care professional who specializes in the assessment and treatment of vision problems, but how is not a medical doctor.
 
Optometrist: vision care specialist. Non-medical professional trained to prescribe eyeglasses or contact lenses, examine eyes, and detect eye disease.
 
OS: a notation used by eye specialists to indicate the left eye.
 
OU: a notation used by eye specialists to indicate both the right and left eyes.
 
Partially sighted: reduced visual acuity, but not legally blind. The measure of distance visual acuity ranging from 20/70 to 20/200 in the better eye after best correction.
 
Peripheral Vision: the ability to see or be aware of what is surrounding us, our side vision. 
 
Photophobia: an abnormal sensitivity to the amount of light entering the eye associated with other visual conditions; may be indicated by squinting or turning away from light source.
 
Ptosis: a drooping of the eyelids occurring in one or both eyes.
 
Pupil: the opening in the center of the iris through which light enters the eye.
 
Plus (+) Lens: convex lens (thicker in the middle) relaxes focusing and converges light. It is typically used in glasses or contact lenses for people who are farsighted (hyperopic).
 
Refractive error: a defect in the eye that prevents light from being focused on the retina.
 
Residual vision: any amount of vision which allows a child to perceive light or discriminate objects.
 
Retina: innermost coat of the eye containing light sensitive nerve cells and fibers connect­ing with the brain through the optic nerve.
 
Retinal detachment: a condition caused by disease or trauma resulting in the retina being pulled away from its normal position.
 
Retinitis Pigmentosa: a hereditary degeneration of the retina where the rods are destroyed generally resulting in decreased visual ability in the peripheral fields.
 
Retinoblastoma: a malignant intraocular tumor which can be uni or bilateral.
 
Retinopathy of Prematurity (ROP): visual impairment associated with prematurity. Formerly called retrolental fibroplasia (RLF) and found in premature infants given oxygen during incubation. ROP can cause decreased visual acuity or total blindness and is usually associated with other disabilities.
 
Retinoscopy: this technique determines the eye's refractive error and the best corrective lenses to be prescribed.
 
Rods: light-sensitive receptors present in the retina which are sensitive to motion and vision at night or in the dark.
 
Sclera: the white part of the eye that forms a tough protective coat.
 
Scotoma: abnormal blind spot in the field of vision surrounded by areas of normal vi­sion.
 
Stereopsis: the ability to perceive a three dimensional depth which requires adequate fusion (union) of the images from each eye.
 
Strabismus: the inability of both eyes to look directly at an object at the same time.
 
Totally blind: without functional vision; may have light perception, but unable to locate source of light.
 
Tuberous Sclerosis: Bourneville’s, a hereditary disorder characterized by seizures, mental retardation, behavior disorders, and skin tumors; eyes may show benign retinal tumors.
 
Tunnel vision: the visual condition where the visual field is severely reduced leaving only a small area of central visual acuity.
 
Stereopsis: the ability to perceive a three dimensional depth which requires adequate fusion (union) of the images from each eye.
 
Vision: the ability to take in information through our eyes and process the information so that it has meaning. 

Visual acuity: the sharpness of vision; the measure of the eye's ability to perceive details and the shape of objects usually measured as a numerical fraction, i.e., 20/200.
 
Visual Discrimination:  the ability to discriminate between visible likeness and differences in size, shape, pattern, form, position, and color. Such as the ability to distinguish between similar words like "ran" and "run".
 
Visual efficiency: the ability to use one's visual acuity effectively and to the maximum extent possible.
 
Visual Field: the total area that can be seen while looking straight ahead.
 
Visual impairment: any condition in the visual system (eye, optic nerve, or visual cortex) that affects the ability to use vision as a primary mode of learning.
 
Visual Memory: the ability to recall and use visual information from the past.
 
Visual-Motor Integration (VMI): after visual data is gathered, it is processed and combined in the brain with information from movement (eye hand coordination). 
 
Visual-Motor Skills: the ability of our eyes to guide our hands (eye hand coordination, visual-motor integration).
 
Visual Skills: accommodation (eye focusing), binocularity (eye teaming), and oculomotor skills (eye movement), which are neuro-muscular abilities that are controlled by muscles inside and outside of the eye and are networked with the brain.