you might expect to see their corresponding arm on that side straightening while the other arm bends up.
The babys hand on the straightened arm should be open, and the other hand will be tightly clenched.
The tonic neck reflex is subtle, and babies do not perform it when upset or crying.
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See a healthcare provider orpediatricianif your baby demonstrates this reflex on one side but not the other.
The asymmetric tonic neck reflex differs from the symmetric one.
The symmetric tonic neck reflex allows a baby to hold their head on all fours, leading to crawling.
This reflex usually appears around 6 to 9 months.
They wont be able to perform the reflex if they are upset or crying.
This is a subtle reflex and it can be challenging to recognize it.
Consult with a healthcare provider if you have tried a few times and still cannot elicit a response.
Additional Reflexes to Recognize
Your baby is born with severalreflexesthat fade over time.
Additional reflexes to recognize include:
The asymmetric tonic neck reflex is often referred to as the fencing posture.
Causes of Ongoing Tonic Neck Reflex as Children Age
The tonic neck reflex disappears on its own.
When a baby continues to demonstrate this reflex after 9 months, its time to see a healthcare provider.
The tonic neck reflex helps a baby to develop muscle strength and hand-eye coordination.
Babies who keep this reflex may have trouble withmotor functionand balance.
In most cases, a missing tonic neck reflex is not a cause for concern.
Healthy babies cannot perform this reflex if upset, crying, or falling asleep.
Babies born without certain reflexes may have experienced an injury or infection.
They are experts at testing for newborn reflexes.
It is present at birth and lasts until 3 to 9 months.
Choose a time when your baby is alert and calm.
If you do not see the reflex, have another go later.
If you develop concerns, call a pediatrician.
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American Academy of Pediatrics.Newborn reflexes.
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