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Glossary of Disorders and Diagnoses

Pervasive Development Disorders (PDD)

Describes extreme developmental abnormalities with onset in the fist three years of life, and that are not normal for any stage of development. PDD represents a distortion in basic development that primarily affects verbal and nonverbal communication, social skills, and imaginative activity. Also, attention, sensory, processing, mood, intellectual functioning, and motor skills can be affected. This is a chronic disorder requiring long term treatment. Currently, Autistic Disorder, Rett’s disorder, Childhood Disintegrative Disorder, Asperger’s Disorder, and PDD not Otherwise Specified are all in the PDD category.

Autistic Disorder

A PDD characterized by a qualitative impairment in social interaction as seen in poor eye contact, inefficient “reading” of facial or body movements, a lack of spontaneous seeking to share enjoyment, interests, or achievements with other people and/or lack of social rhythm such as used in conversation. Communication Impairment can also be manifested as a delay in or lack the development of language and without interest in using mime or gesture to compensate; in individuals with speech, an ability to initiate and maintain a conversation can be present; stereotyped and repetitive language; and/or the lack of varied, spontaneous make believe or social play at an age appropriate level. Restricted repetitive and stereotypic patterns of behavior, interests and activities as seen in an intense preoccupation with a restricted pattern, activity or interest, rigidity to specific, non-functional routines or rituals, repetitive movements such as seen in hand or finger flapping and body rocking; and/or a persistent preoccupation with parts of objects. Delayed or abnormal function in at least one of the following areas prior to the age 3 is also a factor in this diagnosis: social interaction, language used for communicative intent, and/or symbolic or imaginative play. About half of autistic children score below 50 on IQ tests, 20% score between 50 and 70, and 30% score higher than 70. A very small percentage of autistic individuals are considered savants with limited yet extraordinary skills in a specific area. The incident of autism is now thought to effect one person in 500, either reflecting new awareness of the diagnosis, or the genetic, biological, and/or environmental causes.

Rett’s Disorder

A sex-linked genetic type of PDD that effects only girls, characterized by gross and sustained impairment in social interaction of the type that occurs in autism. This differs from an autistic disorder in the lack of a clinically significant delay in cognitive development. Also, during the first 3 years of life, language, self-help, and adaptive behaviors appear normal. Restricted repetitive patterns of behavior are present, and the most marked manifestation of the disorder. After a period of normal development, head growth decelerates, seizures may develop, purposeful hand use diminishes with increasing stereotyped hand movements, poorly coordinated movements develop, and receptive and expressive language becomes severely impaired. Severe mental retardation is usually associated with this disorder.

Autistic spectrum

A family of related disorders including Asperger’s Syndrome, Rett’s Syndrome, Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS) and Childhood’s Disintegrative Disorder.

Childhood Disintegrative Disorder

A PDD characterized by normal development for a period of 2 years, followed by a definite loss of language usually along with abnormal social and communicative functioning. This differs from the Autistic Disorder in that the decline in function continues before age 10 with a further loss of skills such as bowel and bladder control, dementia, play and motor skills.

Asperger’s Disorder

A PDD characterized by impaired social interaction with restrictive, repetitive, and stereotyped patterns of behavior, interests and activities. It differs from an Autistic Disorder in that during the first 3 years of life significant delays in language or in cognitive development are NOT present and adaptive and self-skills often appear normal. Restricted patterns of behavior, interest and activities are present and are a hallmark of this disorder, as well as under developed social skills.

Learning Disorder

Achievement as measured by standardized test, is substantially below what is expected given the child’s age, intelligence level, and school experience. Additionally, the learning problems in reading, math, or written expression significantly interfere with academic achievements of daily activities that require these skills. They affect up to 10% of the population.

Communication Disorder

Involves significant deficits in expressive language or mixed receptive/expressive abilities.

Sensory Integration

The normal, developmental process of the brain and nervous system working together to efficiently organize and process the incoming sensory information into an appropriate response. The senses include tactile, vestibular of movement, visual, auditory, proprioceptive or input from the muscles and joints, and taste and smell. This helps all human beings develop an internal sense of themselves spatial concepts, how to move safety through the environment, and provides a feeling of comfort and safety in the world around them. It is the process which “tells us” if we are going up or down in the elevator with our eyes closed, how to get onto a moving escalators safety, and how to be able to attend to a teacher when a fan is blowing, lights are flickering, and a lawn more if outside. It helps one to be able to focus and attend, and tells us which neural signals to ignore.

Sensory Integrative Dysfunction

This occurs when the nervous system cannot efficiently process incoming sensory information. For example, if a student was distracted by the seams of his socks, the label in his shirt, the kids playing outside, his nervous system might not be able to distinguish between the important from the unimportant. System overload might occur as the student cannot attend to every random stimulus and still listen to the teacher. Some people need huge doses of sensory input in order for them register. Both ends of the continuum can cause difficulties. Over or underreactivity to stimuli, clumsiness, distractibility and poor attention span, seeking out and/or avoidance of certain movements or activities, immature social and emotional responses, difficulty in understanding or using language, lack of muscle strength or tone, and difficulty with transitions might all be signs of a sensory integration disorder.

Down Syndrome

A chromsomal condition (an extra partial or complete 21st chromosome) which occurs 1 in every 800 to 1000 births. Some physical characteristics of the syndrome are slanted eyes with folds at the inner corners, low muscle tone and hyperextensible joints, a flat nasal bridge, enlarged tongue, broad feet with short toes, and short broad hands with single crease across the palm. Congenital heart defects and respiratory problems are often associated with Down Syndrome. Mental retardation is associated with Down Syndrome, though usually in the mild to moderate range. With improved medical care, the life expectancy of individuals with Down Syndrome can be increased.

Cerebral Palsy

A term used to describe a group of chronic conditions affecting body movement and coordination. Mental retardation, perceptual impairments, seizures, feeding, and bowel and bladder problems can also be associated. CP is caused by damage to one or more specific areas of the brain usually during fetal development: before, during, or shortly after birth, or during infancy. CP is non-progressive. As individuals mature varied support services may become vital in attaining and maintaining independence.

Spina Bifida

Also known as “myelmeningocele”, spina bifida is an incomplete closure in the spinal column. The spinal chord and surrounding tissues can protrude and become damaged. This results in varying degrees of paralysis depending on the location and the severity. Hydrocephalus is also associated with spina bifida which is treated by shunting the extra fluid from the brain. Functionally, there may be motor and sensory limitations or loss, perceptual difficulties, and a disruption in bowel and bladder control.

Mental Retardation

A significantly sub average of intellectual functioning diagnosed before 18 years of age. This can be accompanied by impairments in communication, self-care and daily living skills, and/or social skills. Mild retardation is measured as 50-55 to 70, moderate as 35-40 to 50-55, severe as 20-25 to 35-40 and profound as below 20-25.