A reflex is a muscle reaction that happens automatically in response to stimulation. Certain sensations or movements produce specific muscle responses.
The presence and strength of a reflex is an important sign of nervous system development and function.
Many infant reflexes disappear as the child grows older, although some remain through adulthood. A reflex that is still present after the age when it would normally disappear can be a sign of brain or nervous system damage.
Infant reflexes are responses that are normal in infants, but abnormal in other age groups. These include:
Other infant reflexes include:
TONIC NECK REFLEX
This reflex occurs when the head of a child who is relaxed and lying face up is moved to the side. The arm on the side where the head is facing reaches away from the body with the hand partly open. The arm on the side away from the face is flexed and the fist is clenched tightly. Turning the baby's face in the other direction reverses the position. The tonic neck position is often described as the fencer's position because it looks like a fencer's stance.
TRUNCAL INCURVATION OR GALANT REFLEX
This reflex occurs when the side of the infant's spine is stroked or tapped while the infant lies on the stomach. The infant will twitch their hips toward the touch in a dancing movement.
This reflex occurs if you place a finger on the infant's open palm. The hand will close around the finger. Trying to remove the finger causes the grip to tighten. Newborn infants have strong grasps and can almost be lifted up if both hands are grasping your fingers.
This reflex occurs when the baby's cheek is stroked. The infant will turn toward the side that was stroked and begin to make sucking motions.
This reflex occurs in slightly older infants when the child is held upright and the baby's body is rotated quickly to face forward (as in falling). The baby will extend his arms forward as if to break a fall, even though this reflex appears long before the baby walks.
Examples of reflexes that last into adulthood are:
Infant reflexes can occur in adults who have:
The health care provider will often discover abnormal infant reflexes during an exam that is done for another reason. Reflexes that remain longer than they should may be a sign of a nervous system problem.
Parents should talk to their child's provider if:
The provider will perform a physical exam and ask about the child's medical history.
Questions may include:
Reviewed By: Neil K. Kaneshiro, MD, MHA, Clinical Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.