A reflex is a response to a stimulus and that occurs without conscious thought. Examples of adult reflexes include pulling your hand away from a hot stove and jerking your lower leg when the area below your kneecap is tapped.
Babies are born with a unique set of reflexes that can tell a physician about their health and development. Within the first minutes after birth, nurses and doctors assess these reflexes.
Some reflexes from infancy last into adulthood. These include the gag reflex, which causes gagging when the throat is stimulated. However, other reflexes are unique to infants, and they typically grow out of these reflexes within a few months of birth. These reflexes include:
- asymmetrical tonic neck reflex
- Babinski reflex
- grasp reflex
- Moro or startle reflex
- rooting reflex
- step reflex
- truncal incurvation or Galant reflex
Several of these reflexes may be noted immediately after birth. If an adult experiences a brain injury, they may exhibit infant reflexes once more. Examples of injuries that cause these symptoms include brain damage and stroke.
Tests for neonatal reflexes check if babies react appropriately to certain stimuli.
Asymmetrical tonic neck reflex
A baby shows the asymmetrical tonic neck reflex when they are lying down and the head is turned gently to the side. This causes the baby to take on a “fencer” position. This means if the head is turned to the left, the right arm flexes and the left arm reaches straight away from the body with the hand slightly opened. If the baby’s head is turned to the right, the baby will assume the opposite position.
The Babinski reflex is tested by stroking the underside of the baby’s foot, from the top of the sole toward the heel. The baby’s toes will fan out and the big toe will move upward. In an adult, the foot and toes will curl inward.
The grasp reflex is tested by placing a finger in the baby’s open palm. The baby should grasp the finger and may even maintain a firm grip on the finger.
The Moro reflex is tested by gently positioning a baby in a seated stance with the head supported. The professional administering the test lets the baby’s head drop backwards slightly, and then catches the head before it hits the pillow or mat behind it. If a baby’s Moro reflex is present, the baby should appear startled and lift its palms upward, with its thumbs out. When the baby is caught, the baby will bring its arms back to its body.
The rooting reflex is commonly used to achieve a breastfeeding latch. When a baby’s cheek is stroked, the baby will turn toward the cheek that was stroked and will make a gentle sucking motion.
A healthcare provider tests the step reflex by holding the baby upright and gently touching the baby’s feet to a surface. The baby will appear to step or dance.
Truncal incurvation or Galant reflex
The Galant reflex is tested by holding the baby face-down in one hand while using the other hand to stroke the baby’s skin along either side of the spine. The baby’s spine should curve in response, causing the head and feet to move towards the side being stroked.
When to see your doctor
Reflexes that return after they have previously gone away may be cause for concern. If you are concerned about your child’s development, you can ask a doctor to check these reflexes.