Types of Developmental Delays in Children
Pediatric specialists at Hassenfeld Children’s Hospital at NYU Langone identify several types of developmental delays in children. These delays can affect a child’s physical, cognitive, communication, social, emotional, or behavioral skills.
Often, developmental delays affect more than one area of a child’s development. When a child has delays in many or all of these areas, it is called global developmental delay.
Some developmental delays have an identifiable cause. However, for many children, the cause of the delay, or multiple delays, is not clear.
Cognitive delays may affect a child’s intellectual functioning, interfering with awareness and causing learning difficulties that often become apparent after a child begins school. Children with cognitive delays may also have difficulty communicating and playing with others.
This type of delay may occur in children who have experienced a brain injury due to an infection, such as meningitis, which can cause swelling in the brain known as encephalitis. Shaken baby syndrome, seizure disorders, and chromosomal disorders that affect intellectual development, such as Down syndrome, may also increase the risk of a cognitive delay. In most cases, however, it is not possible to identify a clear reason for this type of delay.
Delays in motor skills interfere with a child’s ability to coordinate large muscle groups, such as those in the arms and legs, and smaller muscles, such as those in the hands. Infants with gross motor delays may have difficulty rolling over or crawling; older children with this type of delay may seem clumsy or have trouble walking up and down stairs. Those with fine motor delays may have difficulty holding onto small objects, such as toys, or doing tasks such as tying shoes or brushing teeth.
Some motor delays result from genetic conditions, such as achondroplasia, which causes shortening of the limbs, and conditions that affect the muscles, such as cerebral palsy or muscular dystrophy. They may also be caused by structural problems, such as a discrepancy in limb length.
Social, Emotional, and Behavioral Delays
Children with developmental delays, including those with related neurobehavioral disorders such as autism spectrum disorder and attention deficit hyperactivity disorder, often also have social, emotional, or behavioral delays. Due to differences in brain development, they may process information or react to their environment differently than children of the same age. These delays can have an impact on a child’s ability to learn, communicate, and interact with others.
It is common for children with developmental delays to have difficulty with social and emotional skills. For example, they may have trouble understanding social cues, initiating communication with others, or carrying on two-way conversations. They may also have difficulty dealing with frustration or coping with change. When the environment becomes too socially or emotionally demanding, children with developmental delays may have prolonged tantrums and take longer than other children to calm down. This behavior can be a signal that the child needs more support by modifying his or her environment or learning skills to cope with social and emotional challenges.
Some speech delays are receptive language disorders, in which a child has difficulty understanding words or concepts. Children with this type of speech delay may have trouble identifying colors, body parts, or shapes. Others are expressive language disorders, in which a child has a reduced vocabulary of words and complex sentences for his or her age. A child with this type of speech delay may be slow to babble, talk, and create sentences. Often, a child with a speech delay has a combination of receptive and expressive delays.
Children with an oral motor problem—such as weakness in the muscles of the mouth or difficulty moving the tongue or jaw—that interferes with speech production have what is known as a speech production disorder.
Children may have speech delays due to physiological causes, such as brain damage, genetic syndromes, or hearing loss. Other speech delays are caused by environmental factors, such as a lack of stimulation. In many instances, however, the cause of a child’s speech delay is unknown.