Infant reflexes

Answer 1

Definition

A reflex is an involuntary muscle reaction to a certain type of stimulation. Certain sensations or movements are known to produce specific muscular responses.

Alternative Names

Primitive reflexes; Reflexes in infants; Tonic neck reflex; Galant reflex; Truncal incurvation; Rooting reflex; Parachute reflex; Grasp reflex

Considerations

The presence and strength of a reflex is an important sign of neurological development and function.

Many infant reflexes disappear as the child grows older, although some remain throughout adulthood. The presence of an infant reflex after the age at which the reflex normally disappears can be a sign of brain damage or damage to the nervous system.

Infant reflexes are reflexes that are normal in infants, but abnormal in other age groups. Such reflexes include:

• Moro reflex
• Sucking reflex (sucks when area around mouth stimulated)
• Startle reflex (pulling arms and legs inward after loud noise)
• Step reflex (stepping motions when sole of foot touches hard surface)

Other infant reflexes include:

The TONIC NECK REFLEX is elicited when the head of a relaxed child, lying on his back, is rotated to the side. The arm toward which the infant is facing extends straight away from the body with the hand partially open, while the arm on the side away from the face is flexed and the fist is clenched tightly. Reversing the direction in which the face is turned reverses the position. The tonic neck position is often described as the fencer's position because it resembles the stance of a fencer.

The TRUNCAL INCURVATION or Galant reflex is elicited by stroking or tapping along the side of the spine while the infant lays on the stomach. The infant will twitch his or her hips toward the side of the stimulus in a "dancing' movement.

The GRASP REFLEX is elicited by placing a finger on the infant's open palm. The hand will close around the finger. Attempting to remove the finger causes the grip to tighten. Newborn infants have strong grasps and can almost be lifted from the examination table if both hands are used.

The ROOTING REFLEX is elicited by stroking the cheek. The infant will turn toward the side that was stroked and begin to make sucking motions with its mouth.

The PARACHUTE REFLEX occurs in the slightly older infant, and is elicited by holding the child upright then rotating the body quickly face forward (as if falling). The arms are reflexively extended as if to break a fall even though this reflex appears long before walking.

Examples of reflexes that persist into adulthood are:

• Blinking reflex -- you blink your eyes when they are touched or when sudden bright light appears
• Cough reflex -- you cough when your airway is stimulated
• Gag reflex -- you gag when the throat or back of mouth is stimulated
• Sneeze reflex -- you sneeze when nasal passages are irritated
• Yawn reflex - you yawn when the body needs additional oxygen

Common Causes

Abnormal presence of infant reflexes can occur in adults with:

• Brain damage
• Stroke

Call your health care provider if

Abnormal infant reflexes are usually discovered by the health care provider during exams performed for other reasons. The parents of an infant may be aware of the condition.

What to expect at your health care provider's office

The health care provider will perform a physical examination and ask questions about the child's medical history.

Questions may include:

• What reflexes were present?
• At what age did each infant reflex disappear?
• What other symptoms are also present? (For example, decreased alertness or seizures.)

Answer 2

Definition

A reflex is a muscle reaction that happens automatically in response to a certain type of stimulation. Certain sensations or movements produce specific muscle responses.

Alternative Names

Primitive reflexes; Reflexes in infants; Tonic neck reflex; Galant reflex; Truncal incurvation; Rooting reflex; Parachute reflex; Grasp reflex

Considerations

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 throughout adulthood. The presence of an infant reflex after the age at which the reflex normally disappears can be a sign of brain damage or damage to the nervous system.

Infant reflexes are reflexes that are normal in infants, but abnormal in other age groups. Such reflexes include:

• Moro reflex
• Sucking reflex (sucks when area around mouth is touched)
• Startle reflex (pulling arms and legs in after hearing loud noise)
• Step reflex (stepping motions when sole of foot touches hard surface)

Other infant reflexes include:

The TONIC NECK REFLEX occurs when you move the head of a child who is relaxed and lying on his back to the side. The arm on the side where the head is facing reaches straight 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.

The TRUNCAL INCURVATION or Galant reflex occurs when you stroke or tap along the side of the spine while the infant lays on the stomach. The infant will twitch his or her hips toward the touch in a “dancing' movement.

The GRASP 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.

The ROOTING REFLEX occurs when you stroke the baby's cheek. The infant will turn toward the side that was stroked and begin to make sucking motions with the mouth.

The PARACHUTE REFLEX occurs in slightly older infants, when you hold the child upright and then rotate his body quickly face forward (as if 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:

• Blinking reflex -- blinking the eyes when they are touched or when a sudden bright light appears
• Cough reflex -- coughing when the airway is stimulated
• Gag reflex -- gagging when the throat or back of the mouth is stimulated
• Sneeze reflex -- sneezing when the nasal passages are irritated
• Yawn reflex - yawning when the body needs more oxygen

Common Causes

Infant reflexes can occur in adults who have:

• Brain damage
• Stroke

Call your health care provider if

The health care provider usually discovers abnormal infant reflexes during an exam that is done for another reason. Reflexes that last after they are supposed to have gone away may be a sign of a nervous system problem in the child.

Parents who are worried about their child's development, or who notice that baby reflexes continue in their child after they should have stopped should tell their health care provider.

What to expect at your health care provider's office

The health care provider will perform a physical examination and ask questions about the child's medical history.

Questions may include:

• What reflexes did the baby have?
• At what age did each infant reflex disappear?
• What other symptoms are also present (for example, decreased alertness or seizures)?

Reviewed By

Review Date: 12/01/2011

John Goldenring, MD, MPH, JD, Pediatrician with the Sharp Rees-Stealy Medical Group, San Diego, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.