Symptoms of Children with Intellectual Disability

“Mental retardation” (an outdated term) generally refers to intellectual disability. Intellectual disability is a group of neurodevelopmental disorders characterized clinically by significantly impaired intellectual functioning and difficulties in adaptive behavior. It typically manifests before the central nervous system has fully matured. So, what are the symptoms observed in children with intellectual disability? The following section addresses this question.

Symptoms of Intellectual Disability in Children

1. Absence or lack of smiling

Typically developing infants begin to smile by age 2 months and may laugh aloud when stimulated by 4 months. In contrast, children with intellectual disability often do not smile—or may only exhibit aimless, inappropriate smiling.

2. Delayed motor development

Infants may still be unable to lift their heads at 4 months, sit independently at 10 months, or use their fingers to grasp small objects after 12 months. When beginning to walk, they may display uncoordinated, erratic kicking of both legs.

3. Delayed language development

After age 1 year, affected children may still fail to produce purposeful vocalizations; instead, they may emit random, nonfunctional sounds. Tongue protrusion and drooling—often persisting into ages 2–3 years—may occur during wakefulness.

4. Poor visual tracking and limited eye contact

After 6 months of age, these children may fail to attend to caregivers speaking to them. They often show diminished attention to people and objects in their surroundings, with a fixed, vacant gaze.

5. Feeding difficulties

When introduced to solid foods (e.g., rice or steamed buns) between 6–8 months of age, affected infants frequently experience nausea and vomiting, demonstrate poor chewing ability, and commonly choke or cough during feeding.

6. Absent or abnormal crying response

In response to stimuli, these children may not cry immediately; crying may be delayed or require repeated stimulation. Their cries often differ from those of typically developing infants—either abnormally shrill or weak and feeble.

The above outlines common signs associated with intellectual disability in children. We hope this information is helpful to you.