Asymmetrical Tonic Neck Reflex (ATNR)
The Asymmetrical Tonic Neck Reflex, or ATNR, emerges en utero around 13 weeks of gestation. During pregnancy, the ATNR helps facilitate kicking, develop muscle tone, and stimulate the vestibular system. During birth, the ATNR, in combination with several other reflex patterns, help the baby move through the birth canal. The compression of the birthing process, in turn, reinforces this reflex to make sure it is firmly established and active for the first few months of life (Goddard, 2005, p.10).
Once born, when a baby turns its head to one side, the ATNR reflex allows for air to freely be inhaled and exhaled. The ATNR also helps increase muscle tone, trains one side of the body at a time, and prepares the baby for reaching movements later in life (Goddard, 2005, p.10). This reflex should integrate by 6 months of age.
If the ATNR persists beyond the first six months, the baby will have a difficult time crossing the midline of the body, such as passing an object from one hand to another or using both sides of the body at the same time. This is called bilaterality.
Children with an active ATNR will have an unusual gait, as turning the head will create movement in the hips and a shortening of one leg. Thus, participation in activities like running, playing soccer or playing basketball will be very challenging.
Academically, the ATNR can impact reading and learning in several ways. First of all, a child's visual pursuits will be poor, particularly at the midline. A child must be able to fluidly move their eyes across the page hundreds of times when reading during the day. Poor crossing of the midline also means that neural transmissions are not getting across the corpus callosum effectively, impacting processing and memory. Many of these students end up with a diagnosis of dyslexia. Furthermore, children with an active ATNR may have poor handwriting and/or written expression.
The ATNR is a key reflex pattern in the development of the auditory processing system, which plays a key role in reading and classroom achievement. Phonemic awareness, the ability to hear, identify, discriminate and manipulate the sounds of the language, is a subset of auditory processing and the foundational skill for reading. The ATNR will also impact auditory-visual integration (looking and listening at the same time; looking and speaking at the same time) (Masgutova, 2012)