Developmental Delay

Any delay in a child's physical, cognitive, behavioral, emotional, or social development, due to any number of reasons.

Developmental delay refers to any significant retardation in a child's physical, cognitive, behavioral, emotional, or social development. The two most frequent reasons for classing a child as having developmental delay involve those psychological systems for which there are good norms. This is especially true for motor development and language development. Because it is known that all children begin to crawl by eight months of age and walk by the middle of the second year, any child who was more than five or six months delayed in attaining those two milestones would probably be classified as developmentally delayed and the parents should consult the pediatrician.

Most children begin to speak their first words before they are eighteen months old and by three years of age the vast majority are speaking short sentences. Therefore, any child who is not speaking words or sentences by the third birthday would be considered developmentally delayed and, as in motor development delay, the parent should consult the pediatrician.

The other developmental problems that children show are more often called disabilities rather than delays. Thus, the small group of children with autism do not show normal social development but these children are usually called disabled or autistic rather than developmentally delayed. Similarly, most children are able to read single words by the second grade of elementary school. Children who cannot do that are normally labeled dyslexic or learning disabled, or in some cases academically delayed, rather than developmentally delayed.

Physical development is assessed by progress in both fine and gross motor skills. Possible problems are indicated by muscles that are either too limp or too tight. Jerky or uncertain movements are another cause for concern, as are abnormalities in reflexes. Delays in motor development may indicate the presence of a neurological condition such as mild cerebral palsy or Tourette's syndrome. Neurological problems may also be present when a child's head circumference is increasing either too fast or too slowly. Although physical and cognitive delays may occur together, one is not necessarily a sign of the other.

Important cognitive attainments that physicians look for in infants in the first 18 months include object permanence, an awareness of causality, and different reactions to strangers and family members. Cognitive delays can signal a wide variety of problems, including fetal alcohol syndrome and brain dysfunction. Developmental milestones achieved and then lost should also be investigated, as the loss of function could be sign of a degenerative neurological condition.

Delays in social and emotional development can be among the most difficult for parents, who feel rejected by a child's failure to respond to them on an emotional level. They expect such responses to social cues as smiling, vocalization, and cuddling, and may feel angry or frustrated when their children do not respond. However, a delay in social responses can be caused by a number of factors, including prenatal stress or deprivation, prematurity, birth difficulties, including oxygen deprivation, or a hypersensitivity of the nervous system (which creates an aversion to stimuli that are normally tolerated or welcomed).

Many physicians routinely include developmental screening in physical examinations. Parents concerned about any aspect of their child's development are generally advised to seek the opinion of a pediatrician or appropriate specialist. Specific assessment instruments such as the Gesell Development Scales and the Bayley Scales of Infant Development are used to help determine whether an infant is developing at a rate appropriate to the child's age.