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Etymology: L, extrudere, to push out, reflectere, to bend back
a normal response in infants to force the tongue outward when it is touched or depressed. The reflex begins to disappear by about 3 or 4 months of age. Constant protrusion of a large tongue may be a sign of Down syndrome.
ex·tru·sion re·flex(eks-trū'zhŭn rē'fleks)
When a spoon is put into an infant's mouth, the tongue automatically thrusts forward.
An infantile reflex in which the tongue moves outward after it has been touched. It is present from birth to 4 months.
See also: reflex