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Understanding Childhood Disabilities

Causes and Assessments of Disabilities in Children

"Normal" childhood development spans many parameters, and often even "abnormal" behaviors will disappear in time. In Understanding Cognitive and Social Development in a Newborn, we describe developmental markers that are currently accepted as "normal." If you believe your child's behavior is consistently falling outside the normal range, you should consult your pediatrician. On this page, we explain some of the causes for developmental problems as well as special evaluations and assessments for disabilites.

Developmental Problems: Possible Causes

Some infants have inborn defects, such as brain damage and incomplete development of the brain, that prevent normal development. Others suffer from conditions or diseases that can be treated once they are identified. One rare inherited metabolic disease, for which infants are tested a few days after birth or at their first visit to the doctor, is phenylketonuria (PKU). Untreated, the disease leads to mental retardation, but early detection and prompt treatment through diet usually ensure development of average intelligence. Another test newborns undergo is for congenital hypothyroidism, which is also rare and also capable of causing retardation if untreated.

Infants born with some defects may not appear abnormal immediately, but most display marked delays in development that their parents observe or their doctors notice. At each checkup, your child's doctor observes your child's behavior as a clue to development. He or she, or an assistant, may also do quick screening tests at certain ages in your child's life. In both the observation and the tests, the physician is looking for possible danger signals.

Other infants, normal at birth, suffer later from incompetent or insufficient nurturing. Environmental problems are often more difficult for a doctor to identify than inborn defects, and they can pose serious hazards to a child's development. Some of the clues that alert the physician are these:

  • Disturbances of eating or sleeping (either insufficient or excessive). Both the quantity and the quality of parental care influence an infant's own regulation of eating and sleeping.
  • Physical symptoms, such as frequent vomiting, diarrhea, and skin rashes.
  • Failure to grow normally in height and weight. An infant deprived of loving nurture may fail to grow in spite of adequate food intake. If a lack of nurturing can be ruled out, the physician investigates suppression of growth factors in the baby's brain.
  • Marked delay or deviation in specific areas, such as motor development, verbal ability, intellectual development, and general learning, or in development of relationships to others, a sense of self, or the capacity to play.

Frequently, when the necessary nurturing ingredients are lacking, children develop various medical or psychological problems. For instance, if bonding does not occur between mother and infant, it is not unusual to find failure to thrive behavioral problems as well as a disturbed mother-child relationship. This does not mean there is automatically trouble if the ideal bonding process does not take place immediately following birth. Recent studies have shown that mothers of cesarean-birth, premature, or adopted babies can successfully bond later.

Likewise, parents who are aware of their own imperfections and lack of knowledge need not worry that, because of their shortcomings, their baby's ability to develop is automatically damaged. Babies have a strong drive toward normal development that helps them resist "less-than-ideal" environmental factors. Clearly, the ability of infants to develop can be damaged in situations of poor care, but none of us is without flaws. We should do the very best we can for our children, but we need not be perfect to raise fine human beings.

Parents who are concerned about some aspect of their infant's or child's development or, later, about behavioral problems should turn first to their doctor. Sometimes one's inclination is to avoid bothering the doctor, and it is true time is a precious commodity for a doctor. Still, if the doctor seems unwilling to discuss what the parents see as a problem, or refuses for some reason to become involved in the parents' worries, it is wise to choose another physician. If more than average time is required for an office visit to discuss behavioral problems, some doctors charge more, but you can count extra fees as money well spent if you are able to head off serious problems.

Special Developmental Evaluations

Occasionally a child whose problems may be as specific as slow speech development or as general as overall slow development needs the attention of a developmentalist, a pediatrician whose subspecialty is early childhood development. Parents who suspect a developmental lag in either motor or cognitive development, or see signs their baby refuses to be socialized or is withdrawn and depressed, can ask for an evaluation by such a specialist, or their child's doctor may recommend it. The developmentalist, perhaps working with a team of other professionals, such as social workers and psychologists, observes the child performing various functions in a play-like situation to determine the existence and extent of developmental problems. Other specialists may be called in as consultants.

After an assessment, the developmentalist will discuss with the parents his or her findings and recommendations for treatment. Unfortunately, some parents learn their fears of retardation have been confirmed. Others receive the relief of assurance that their child can develop normally, perhaps with special help. Whatever the outcome of the evaluation, parents should strive for a proper balance in their reactions. Hysterical overconcern helps neither their child nor themselves, and trying to insulate themselves against pain and hurt by noninvolvement is likewise an inappropriate response.

Assessing Disability

All children can learn and develop. But children do not learn and develop in the same way or at the same rate. Sometimes parents notice an overall pattern of slowness in a child's responses to the world around her. Parents may notice the child's general physical growth and achievement seem to lag far behind those of other children.

Some children don't seem to develop normal sensory responses. Children with impaired vision, for instance, may not focus or follow with their eyes. A child with impaired hearing may not respond to sounds or may fail to speak or make prespeech sounds, or she may babble later and less frequently than children with normal hearing.

When parents perceive a consistent pattern of delays, they will want their child evaluated by a professional. Part of that assessment includes an effort to determine possible causes of the problem or problems.

Possible causes of developmental problems are many. Early in the development of the fetus, for example, a spontaneous change in the chromosomes or in individual genes may lead to Down syndrome, a disabling condition that causes affected children to develop and grow more slowly than normal children. Premature birth can sometimes lead to developmental difficulties. Certain infections the mother carried may affect the fetus in its early stages and may lead to retardation and other abnormalities. A trauma suffered during birth or shortly before or after birth may adversely affect a child and can lead to such conditions as cerebral palsy. Certain childhood illnesses, such as encephalitis and meningitis, may also leave a child with mental or physical disabilities.

It is not always possible to determine the cause of a disabling condition; some developmental delays are difficult to diagnose. An IQ (intelligence quotient) score below 69 indicates a child may be mentally retarded (90 to 109 is considered average). But the diagnosis of a disability should not rest solely on an IQ test score. A child's adaptive behavior -- his ability to respond to stimuli, to learn and grow -- should also be measured. There are, however, no absolute tests that can tell us how quickly a child with a disability will move through developmental stages, or how much the child will eventually accomplish.

Common developmental problems are delayed speech and/or hearing loss, which are often related. In the next section, you'll read about identifying the symptoms, testing, and treatments for speech problems and deafness.

This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.