Lateralization of tongue movements during eating in children 2 to 5 years old.

Normative data on skills of the tongue used in eating are presented. Normal children 2 to 5 years old were studied regarding their preference of placing food either on the right or left side when eating, and they were compared with age-matched Down's syndrome children. In addition, the ability to move food from the right to the left side of the mouth was studied. Normal children underwent a transition from predominantly placing food on the right side at 2 years of age to predominantly placing it on the left side at 4 years of age. Among Down's syndrome children females preferred the right side, and males preferred the left side. The ability to move food from right to left (lateralizing) undergoes a developmental progression from tilting the head to rolling, followed by slow and eventually by smooth movement from one side to the other. Only 15% of the 5-year-olds were able to move food smoothly from side to side. These data provide a baseline against which children with eating problems can be compared.