Palmar grasp reflex
Palmar grasp reflex (sometimes simply called grasp reflex) is a primitive reflex. A fetus can exhibit the reflex in utero as early as 16 weeks into the gestation period, and persists until five or six months of age. When an object is placed in an infant's hand and the palm of the child is stroked, the fingers will close reflexively, as the object is grasped via palmar grasp. The grip is strong but unpredictable; though it may be able to support the child's weight, they may also release their grip suddenly and without warning. The reverse motion can be induced by stroking the back or side of the hand.
If palmar grasp reflex persists beyond 2 to 4 months, it delays or affects functions like grasping a rattle, releasing objects from hand and also hand manipulation skills. Palmar grasp reflex in adults is a pathological frontal release sign and may signify frontal lobe damage, or may be a sign of anterior cerebral artery syndrome.
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