The Asymmetrical Tonic Neck Reflex (ATNR): Developmental Significance, Functional Impact, and What Parents Should Know

Author: Earl Mamaril, MS, OTR/L (Pediatric Occupational Therapist)
Article type: Educational review for parents 

Abstract

The Asymmetrical Tonic Neck Reflex (ATNR) is a primitive, brainstem-mediated reflex that emerges prenatally and typically integrates in early infancy. Appropriate integration supports early postural control, midline awareness, and the foundations of eye–hand coordination. When the ATNR persists beyond infancy, studies associate it with fine- and gross-motor challenges, oculomotor (eye movement) inefficiencies, attention and reading difficulties, and higher rates of retained reflexes in certain neurodevelopmental conditions (e.g., ADHD, ASD). This review summarizes ATNR development and purpose, functional impact when poorly integrated, common co-occurring diagnoses, and proposed contributing factors to retention. It also outlines practical next steps for parents considering pediatric occupational therapy evaluation. (Modrell, 2023; Gieysztor et al., 2018; Konicarova & Bob, 2013; McPhillips & Jordan-Black, 2007; Melillo et al., 2022). PMC+4NCBI+4PMC+4

Keywords

ATNR reflex; primitive reflexes; child development; fine motor skills; gross motor skills; oculomotor control; reading; ADHD; autism; pediatric occupational therapy

Introduction

Primitive reflexes are automatic motor responses originating in the brainstem that support survival and early neurodevelopment. They normally become inhibited as cortical control matures in the first months of life (Modrell, 2023). The ATNR—often called the “fencer’s posture”—links head rotation with extension of the arm/leg on the face side and flexion on the skull side. It typically appears late in gestation and is expected to integrate during early infancy, making way for voluntary, symmetrical movement and bilateral coordination (Modrell, 2023). NCBI

Developmental Meaning and Purpose of ATNR

Functionally, ATNR helps the infant practice coupling head movement with limb activation, laying groundwork for midline awareness, early reaching, eye–hand coordination, and later skills like crossing midline and handwriting (Modrell, 2023). It supports transitional postures and the shift from reflex-driven movement to volitional control as corticospinal pathways mature. In short: ATNR is a temporary “training wheel” that should fade as higher-level control emerges. NCBI

What Happens When ATNR Is Poorly Integrated?

1) Motor development (fine and gross)

Multiple studies show that higher levels of retained primitive reflexes, including ATNR, correlate with lower motor efficiency in otherwise healthy children (Gieysztor et al., 2018). Findings include clumsiness, immature bilateral coordination, and reduced fine-motor precision affecting tool use and handwriting. (Gieysztor et al., 2018). PMC

2) Visual function (oculomotor control, reading)

A retained ATNR is associated with midline crossing difficulty and inefficient eye movements. Research links reflex persistence—particularly ATNR—with poorer core literacy skills and reading performance (McPhillips & Jordan-Black, 2007). Emerging work also shows changes in eye-movement performance in children evaluated before and after reflex-inhibition therapies, suggesting a relationship between primitive reflex status and oculomotor control (Domingo-Sanz et al., 2024). inpp.info+1

3) Attention and self-regulation

In clinical samples, persistent primitive reflexes (including ATNR) have been associated with ADHD symptoms (Konicarova & Bob, 2013) and, in broader analyses, with attention/balance deficits—showing sex-specific patterns for ATNR and STNR (Bob et al., 2021). These are correlational findings; they do not prove causation, but they help explain why some children with attention challenges also show retained reflexes on screening. PMC+1

Associations With Neurodevelopmental Diagnoses

Retained primitive reflexes are reported more frequently in certain neurodevelopmental conditions. Reviews in autism spectrum disorder (ASD) describe close relationships between retained reflexes and cognitive/motor function and discuss the potential for change when reflex activity decreases (Melillo et al., 2022). Reflex persistence is also frequently studied in ADHD cohorts (Konicarova & Bob, 2013; Bob et al., 2021) and has been described in children with coordination and learning difficulties (McPhillips & Jordan-Black, 2007). inpp.info+3PMC+3PMC+3

Contributing Factors (What Might Keep ATNR “On”)

The most robust medical literature ties persistent primitive reflexes to central nervous system immaturity or injury (e.g., in cerebral palsy) and uses reflexes as part of neurologic examinations (Zafeiriou, 2004). Occupational therapy clinical sources propose additional perinatal and environmental contributors—such as cesarean/assisted delivery, limited tummy time, early walking with minimal crawling, chronic ear infections, or head injury—but rigorous causal evidence is limited, and these should be viewed as hypotheses that warrant further study (Zafeiriou, 2004; Frauwirth, 2021). PubMed+1

Balanced takeaway for parents: if your child had perinatal complications or missed early movement experiences, reflex persistence is possible, not guaranteed. A skilled pediatric OT can screen for retained reflexes within a broader, function-focused evaluation.

Screening and Occupational Therapy Approach

• Screening: Pediatric OTs observe posture, crossing midline, handwriting mechanics, and oculomotor skills, then perform simple head-turn tests for ATNR while the child is in stable positions. Findings are interpreted alongside functional goals—not in isolation (Modrell, 2023; AOTA Everyday Evidence, 2022). NCBI+1
• Intervention: Therapy plans emphasize functional, play-based activities that build postural control, bilateral coordination, eye–hand coordination, and self-regulation. Reflex-reduction activities (e.g., rhythmic movement patterns) may be included as preparatory methods, but clinical goals remain occupation-centered (reading, dressing, classroom participation).
• Evidence note: The evidence base linking reflex-integration techniques to broad academic or behavioral outcomes is evolving. Parents should expect individualized treatment plans with measurable, functional outcomes.

Parent Checklist: Signs That May Warrant an OT Evaluation

• Tires quickly with handwriting; “floating elbow” or head/torso turns with writing/reading
• Avoids crossing midline; inconsistent hand dominance after age 6–7
• Clumsy in sports requiring two-handed coordination (e.g., catch/throw)
• Skips words/lines, loses place when reading; difficulty tracking across pages
• Distractibility or motor restlessness that worsens with desk tasks

(A retained ATNR is one possible contributor among many; an OT evaluation looks at the whole child.)

Limitations of the Evidence

• Many studies are cross-sectional (correlational). They show associations, not causation.
• Sample sizes can be small, with variable protocols for reflex testing across studies.
• While some interventional studies and clinical reports describe improvements in motor/oculomotor function alongside decreased reflex activity, high-quality randomized controlled trials remain limited.
• Professional guidance (AOTA) emphasizes function-focused care and careful interpretation of reflex findings within comprehensive, family-centered practice (AOTA Everyday Evidence, 2022). AOTA

Practical Next Steps for Families (Bangor–Brewer, ME and beyond)

1. Talk with your pediatrician and request an OT referral if concerns persist about handwriting, reading endurance, motor coordination, or self-regulation.
2. Schedule a pediatric OT evaluation. Ask that screening include posture/core strength, bilateral coordination, oculomotor skills, and—if appropriate—primitive reflexes, including ATNR.
3. Focus on function at home: tummy time for infants; cross-lateral play (crawling, climbing), ball games, drawing/coloring, and calm-body routines (deep pressure, heavy work) for older children.
4. Track what matters to your child: fewer meltdowns during homework, improved stamina for writing, smoother ball skills, or easier page tracking.

Conclusion

ATNR is a normal, temporary building block of infant development. When it lingers, it may be one factor among many that makes schoolwork, sports, or attention harder. Evidence-based pediatric OT looks at how ATNR relates to your child’s real-life goals—and then uses targeted, playful, and family-centered strategies to build the skills that matter most. (Modrell, 2023; Gieysztor et al., 2018; McPhillips & Jordan-Black, 2007; Konicarova & Bob, 2013; Melillo et al., 2022). PMC+4NCBI+4PMC+4

References (APA 7th)

• Bob, P., Konicarova, J., & Raboch, J. (2021). Disinhibition of primitive reflexes in attention deficit and hyperactivity disorder (ADHD). Frontiers in Psychiatry, 12, 430685.
• Domingo-Sanz, V. A., et al. (2024). Persistence of primitive reflexes associated with oculomotor function in children. BMC Ophthalmology, 24, 204.
• Frauwirth, S. (2021). Understanding primitive reflexes: How they impact child development. OccupationalTherapy.com (CE article).
• Gieysztor, E. Z., Choińska, A. M., & Paprocka-Borowicz, M. (2018). Persistence of primitive reflexes and associated motor problems in healthy preschool children. Frontiers in Psychology, 9, 450.
• Konicarova, J., & Bob, P. (2013). Persisting primitive reflexes in medication-naïve girls with ADHD. Neuropsychiatric Disease and Treatment, 9, 1393–1397.
• McPhillips, M., & Jordan-Black, J.-A. (2007). Primary reflex persistence and reading difficulties. Neuropsychologia, 45(4), 748–754.
• Melillo, R., et al. (2022). Retained primitive reflexes and potential for intervention in autism spectrum disorders. Frontiers in Neurology, 13, 922322.
• Modrell, A. K. (2023). Primitive reflexes. In StatPearls. StatPearls Publishing.
• Zafeiriou, D. I. (2004). Primitive reflexes and postural reactions in the neurodevelopmental examination. Pediatric Neurology, 31(1), 1–8.