A Glossary of Common Disabilities

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A – B   |   C – D   |   E – G   |   H – L   |   M – O   |   P – S  |   T – Z


Alzheimer’s Disease
A progressive, incurable condition that destroys brain cells, gradually causing loss of intellectual abilities such as memory and potentially creating changes in personality or behaviors.

Amyotrophic Lateral Sclerosis (ALS)
Commonly known as Lou Gehrig’s disease, ALS is a progressive neuromuscular disease that causes degeneration of the motor neurons, nerve cells that control the movement of voluntary muscles. The disease causes the motor neurons to degenerate and eventually die. As they die, the corresponding muscles are paralyzed.

Angelman Syndrome
A rare neuro-genetic disorder that occurs in 1 in 15,000 live births. It is often misdiagnosed as cerebral palsy or autism. Characteristics of Angelman Syndrome include developmental delay, lack of speech, seizures, a happy demeanor, walking and balance disorders and jerky movements especially hand-flapping, frequent laughter or smiling.

Asperger’s Syndrome
A pervasive developmental disorder commonly referred to as a form of “high-functioning” autism. Individuals with Asperger’s are considered to have a higher intellectual capacity while suffering from a lower social capacity.

Wobbliness. lack of coordination and unsteadiness due to the brain’s failure to regulate the body’s posture and regulate the strength and direction of limb movements. Ataxia is usually a consequence of disease in the brain, specifically in the cerebellum which lies beneath the back part of the cerebrum.

Attention Deficit/Hyperactivity Disorder (ADHD)
A regular developmental and behavioral disorder characterized by poor concentration, distractibility, hyperactivity, and impulsiveness. Children and adults affected with ADHD are easily distracted by sights and sounds in their environment, cannot concentrate for long periods of time, are restless and impulsive, or have a tendency to daydream and be sluggish to a complete task

Classified by the World Health Organization and American Psychological Association as a developmental disability that results from a disorder of the human central nervous system, it is diagnosed by impairments to social interaction, communication, interests, imagination, and activities.

Autism Spectrum Disorders
This refers to a variety of neurological disorders that most markedly involve some degree of complexity with communication and interpersonal relationships as well as obsessions and repetitive behaviors. As the term “spectrum” indicates, there can be a wide range of effects. Those at the lower-functioning end of the spectrum may be profoundly unable to break out of their own world and may be described as having Kanner’s Autism. Those at the higher-functioning end, sometimes diagnosed with Asperger’s Syndrome, may be able to lead independent lives but may still be awkward in their social interactions.

Bipolar Disorder
Characterized by periods of excitability (mania) alternating with periods of depression. The mood swings between mania and depression can be very abrupt. Bipolar disorder affects men and women equally and usually appears between the ages of 15 and 25. The exact cause is unknown but it occurs more often in relatives of people with bipolar disorder. Bipolar disorder results from disturbances in the areas of the brain that regulate mood. During manic periods, a person with bipolar disorder may be overly impulsive and energetic with an exaggerated sense of self. The depressed phase brings overwhelming feelings of anxiety, low self-worth, and suicidal thoughts.

The loss or diminished ability to perceive visual images. Blindness is the condition of a person having less than 1/10 normal vision, 20/200, on the Snellen test.

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Cerebral Palsy
A general term for a group of permanent brain injuries that affect an infant in the womb, during birth, or in the months following birth.  People with cerebral palsy may have limited motor skills, speech difficulties, learning disabilities, or other related conditions.

Cornelia de Lange Syndrome (CdLS)
A syndrome of multiple congenital anomalies characterized by a distinctive facial appearance, prenatal and postnatal growth deficiency, feeding difficulties, psychomotor delay, behavioral problems, and associated malformations that mainly involve the upper extremities.

Defined as partial or complete hearing loss. Levels of hearing impairment vary from a mild but important loss of sensitivity to a total loss of hearing. Older adults suffer most often from hearing loss. Age-related hearing loss affects 30 to 35 percent of the population between the ages of 65 and 75 years and 40 percent of the population over the age of 75. The most common cause of hearing loss in children is otitis media, a disorder that affects predominantly infants and young children. Many sensorineural hearing losses result from a genetic predisposition.

A mental illness in which people experience sadness, lack of interest in everyday activities and events, and feel a sense of worthlessness.  Depression can be triggered by a tragic event or no apparent cause.

Developmental Disability
A disability that manifests before a person reaches 22 years of age and that constitutes a substantial disability to the affected individual. Developmental disability is attributable to mental retardation or related conditions, which include cerebral palsy, epilepsy, autism, or other neurological conditions when such conditions result in the impairment of general intellectual functioning or adaptive behavior similar to that of a person with mental retardation.

Down Syndrome
A developmental disability that causes slowed growth, abnormal facial features, and mental retardation. Down syndrome is caused by an extra copy of all or part of chromosome 21. Many individuals with Down Syndrome develop Alzheimer’s disease in adulthood.

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When nerve cells in the brain fire electrical impulses at a rate of up to four times higher than normal causing an “electrical storm” in the brain known as a seizure. A pattern of repeated seizures is referred to as epilepsy. Known causes include head injuries, brain tumors, lead poisoning, mal-development of the brain, and genetic and infectious illnesses.

Fetal Alcohol Spectrum Disorder (FASD)
An umbrella term used to explain the range of effects that can occur to an individual whose mother drank alcohol during pregnancy. These effects may include physical, mental, behavioral, and/or learning disabilities with possible lifelong implications.

Five P Minus Syndrome
The Syndrome is characterized at birth by a high pitched cry, low birth weight, poor muscle tone, microcephaly, and potential medical complications. “5p-” is a term used by geneticists to describe a portion of chromosome number five that is missing in these individuals. Most individuals who have 5p- Syndrome have difficulty with language. Some become able to use short sentences, while others express themselves with a few basic words, gestures, or sign language.

Fragile X
The most common inherited form of mental retardation, it results from a change, or mutation, in a single gene, which can be passed from one generation to the next. It occurs because the mutated gene cannot produce enough of a protein that is needed by the body’s cells, especially cells in the brain, to develop and function normally. The amount and usability of this protein, in part, determine how severe the effects of Fragile X are. In addition, having Fragile X is often associated with problems with sensation, emotion, and behavior.

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Human Immunodeficiency Virus (HIV/AIDS)
A retrovirus that consists of Ribonucleic Acid (RNA) and contains a special viral enzyme called Reverse Transcriptase, which allows the virus to convert its RNA to DNA and then integrate and take over a cell’s genetic material. Once the genetic material has been taken over, the new HIV-infected cell begins to produce new HIV retroviruses. HIV replicates in and kills the helper T cells, which are the body’s main defense against illness. AIDS (acquired immunodeficiency syndrome) is caused when the infection advances. Advancement occurs when the viral load is below 200/ml and is characterized by the appearance of opportunistic infections, which take advantage of a weakened immune system.

A build up of fluid inside the skull due to a problem with the flow of cerebrospinal fluid (CSF), the liquid that surrounds the brain and spinal cord. This build leads to brain swelling. Hydrocephalus means “water on the brain.”

Learning Disability
A disorder in basic psychological processes involved in understanding or using language, that manifests itself in an imperfect ability to listen, think, speak, read, write, spell, or use mathematical calculations. The term includes conditions such as perceptual disability, brain injury, minimal brain dysfunction, dyslexia, and developmental aphasia.

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Mental Illness
Health conditions that are characterized by alterations in thinking, mood, or behavior (or some combination thereof) associated with distress and/or impaired functioning.

Mosaic Down Syndrome
Mosaic Down syndrome accounts for about 2 to 4% of all cases of Down syndrome. This results when some of the cells in the body are normal and other cells have trisomy 21.

Multiple Sclerosis (MS)
A chronic degenerative disease of the central nervous system in which gradual destruction of myelin occurs in patches throughout the brain or spinal cord (or both). This deterioration interferes with the nerve pathways, causing muscular weakness, loss of coordination and speech, and visual disturbances. It occurs chiefly in young adults and is thought to be a defect in the immune system that may be of genetic or viral origin.

Muscular Dystrophy (MD)
A broad term used to describe a genetic disorder of the muscles. MD causes the muscles in the body to become very weak. Over time the muscles break down and are replaced with fatty deposits.

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Posttraumatic Stress Disorder (PTSD)
An anxiety disorder that can take place after you have been through a traumatic event. A traumatic event is something horrible and scary that you see or that happens to you. During this type of event, you think that your life or others’ lives are in danger. You may feel afraid or feel that you have no control over what is happening.

Prader-Willi Syndrome
The most common known genetic cause of life-threatening obesity in children. Although the cause is complex it results from an abnormality on the 15th chromosome. PWS typically causes low muscle tone, short stature if not treated with growth hormone, incomplete sexual development, and a chronic feeling of hunger that, coupled with a metabolism that utilizes drastically fewer calories than normal, can lead to excessive eating and life-threatening obesity.

Rett Syndrome
A disorder of the nervous system that leads to developmental reversals, especially in the areas of expressive language and hand use. Rett syndrome occurs almost exclusively in girls and may be misdiagnosed as autism or cerebral palsy.

Sotos Syndrome
A rare genetic disorder characterized by excessive physical growth during the first few years of life. Children with Sotos syndrome tend to be large at birth and are often taller, heavier, and have larger heads (macrocrania) than what is normal for their age. Symptoms of the disorder, which vary among individuals, include a disproportionately large and long head with a slightly protrusive forehead, large hands and feet, hypertelorism (an abnormally increased distance between the eyes), and down-slanting eyes. The disorder is often accompanied by mild mental retardation; delayed motor, cognitive, and social development; hypotonia (low muscle tone), and speech impairments.

Spina Bifida
A developmental disability resulting from the incorrect development of the spinal cord that can leave the spinal cord exposed.

Spinal Cord Injury (SCI)
Damage or trauma to the spinal cord that results in a loss or impaired function causing reduced mobility or feeling. The spinal cord does not have to be severed in order for a loss of functioning to occur. In most people with SCI, the spinal cord is intact but the cellular damage results in loss of function.

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Traumatic Brain Injury (TBI)
Refers to the effects on the brain after a head injury. Traumatic brain injuries can lead to a spectrum of problems including concussion, contusion (hemorrhage within the brain), or diffuse injuries that cause more severe neurological deficits.

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