The asymmetric tonic neck reflex prepares babies for movements such as turning from back to front and vies versa, as well as hand eye coordination and activities involving crossing the midline of the body. This reflex also facilitates the birthing process, allowing the baby to move in a way where they can pass through the birth canal. When this reflex is present, turning the head to one side while lying on their back will cause the arm and leg on the same side to straighten, and to flex on the other side. This reflex is present at birth and should integrate at 4-6 months.

When retained, symptoms may include:

• Possible scoliosis
• Poor handwriting
• Difficulty expressing ideas in written form
• Difficulty with eye tracking
• Difficulty with hand eye coordination and activities involving crossing the midline 
• Difficulty with tasks that require both sides of the body
• Chronic or recurrent shoulder or neck pain