Learning to Learn Part 2: Primitive Reflexes

In Learning to Learn Part 1 two fifth graders sat through the same lesson and earned the same quiz score. The difference between them was not intelligence or effort but how much work each child’s body had to do to get there. That developmental sequence starts before a baby is born.

Key takeaways

• Primitive reflexes are automatic brain-stem movement patterns that help a baby survive birth and early infancy.
• Most fade during the first year; several should be gone by 4 to 6 months (Chamarthi et al., 2026).
• The reflex-integration model holds that a lingering reflex costs a child effort to hold back, leaving less attention for reading and desk work. That is the field’s working explanation, not a measured finding.
• The research linking retained reflexes to learning is small and mostly correlational. We treat a retained reflex as a screening observation, never a diagnosis.

What primitive reflexes are

Development begins with automatic movement patterns generated in the brain stem. They are essential during birth and the first weeks of life, and they lay down muscle tone, head control and early sensory experience. As the brain matures, movement becomes voluntary and these reflexes give way to refined, cortically directed control. Child neurologists have long used them as a simple check on whether an infant’s nervous system is on schedule; persistence or delayed disappearance is a classic finding in cerebral palsy (Zafeiriou, 2004).

A typical integration timeline

Ranges differ by source; a standard clinical summary gives (Chamarthi et al., 2026):

• Moro — 28 weeks of gestation to about 4 to 6 months.
• Asymmetric tonic neck reflex (ATNR) — 35 weeks, integrated by 3 to 4 months.
• Spinal Galant — 32 weeks, gone by 4 to 6 months.
• Rooting and palmar grasp — 28 weeks, gone by 4 to 6 months.
• Plantar grasp — 28 weeks, lasting to about 9 to 12 months.

Clear persistence past 4 to 6 months is associated with neurodevelopmental conditions, particularly cerebral palsy and autism spectrum disorders (Chamarthi et al., 2026), and belongs with your pediatrician. What we see more often is subtler: a faint remnant of a pattern in an otherwise healthy child.

Why a lingering pattern is thought to cost energy

The reflex-integration model holds that when a reflex outstays its span, the body spends effort suppressing it, leaving less attention for reading, copying from the board or sitting through a lesson. That is the field’s explanation rather than a demonstrated one; none of the studies below measured the effort or attention a retained reflex actually consumes. The same literature blames stress in pregnancy, limited movement in utero, long stretches in car seats or walkers, illness, and other delays for the retention itself. Those too are proposed explanations, not established causes.

Five patterns we watch for

The signs below are what clinicians in this field look for, not proven cause and effect.

• Moro. The startle response: head back, limbs out and then in, set off by sudden movement or noise. Linked clinically with sound sensitivity and lost visual attention.
• Tonic labyrinthine reflex (TLR). Looking up straightens the limbs; dropping the head folds them in. It feeds the vestibular system; retention is associated with poor posture, balance and sequencing.
• Symmetric tonic neck reflex (STNR). Looking up straightens the arms and bends the legs; looking down reverses it. Integrating it is part of crawling, which builds eye-hand coordination and tracking. Associated with slow copying and a propped desk posture.
• Spinal Galant. Stroking the lower back near the spine curves the hip outward. Associated with fidgeting and trouble sitting still.
• ATNR. Turning the head straightens the limbs on the face side and bends the others. It is among the reflexes most often examined in this literature, alongside the STNR and the tonic labyrinthine reflex (Provazník et al., 2026), and is associated with midline crossing, tracking, balance and handwriting.

What this looks like at a desk

A child writing drops the head to see the page, and a retained STNR pulls the arms toward flexion just when a quiet, stable arm is needed. Turn the head to the side instead and a retained ATNR nudges the writing arm to straighten and the fingers to open. Either way the grip tightens, and the child may shift the whole body or rotate the paper 90 degrees to escape the pattern. On this model that effort comes out of the same pool the brain needs for spelling and ideas, which is why a child with strong verbal skills who freezes at writing sends us looking at posture.

Back in the classroom, Student A sits with both feet flat, crosses the midline easily and moves from board to page without losing the place. Student B wraps their feet around the chair legs, avoids the midline and writes illegibly, which is what makes us look at STNR and ATNR; the restlessness raises the Galant, the sound sensitivity the Moro and TLR. None of it is a diagnosis. It tells us where to look during the evaluation.

What the research actually shows

We use this framework in the clinic, and families deserve to know how thin the evidence behind it is.

• A double-blind randomized trial of 60 children aged 8 to 11 with reading difficulties found that a movement program replicating primary reflex patterns reduced the ATNR, while placebo movements and no movement did not (McPhillips et al., 2000). One small trial, more than 25 years old, and the outcome it quantified was the reflex itself.
• Drawn from a cross-sectional sample of 409 nine- and ten-year-olds, three groups of 41 were reflex-tested: the bottom 10% of readers showed more persistent ATNR (mean 1.56) than the middle (0.56) or top (0.59) 10%. The same authors concluded that reflex persistence “cannot be used as a causal model for reading difficulties, including dyslexia” (McPhillips & Sheehy, 2004).
• The rest is observational and thin: 65% of 35 healthy preschoolers showed residual reflex activity, with greater severity tied to lower motor efficiency (Gieysztor et al., 2018); four small studies (229 children) pooled to moderate correlations with ADHD symptoms (Wang et al., 2023); a review of 27 preschool studies found only three with reflex data at all (McWhirter et al., 2024); and a 2026 review called the intervention studies “promising” rather than proven (Provazník et al., 2026). Correlation is not causation.

Professional bodies disagree here too. The 2009 joint statement of the American Academy of Pediatrics, the American Academy of Ophthalmology and allied groups says that most experts believe dyslexia is a language-based disorder, and that scientific evidence does not support eye exercises or behavioral vision therapy for learning disabilities (AAP/AAO/AAPOS/AACO, 2009). The optometric position is that “vision problems can and often do interfere with learning,” and that optometric care is one part of a multidisciplinary approach (AAO/AOA, 1997).

Our view sits inside that second position, offered as our clinical perspective. Reflex observations tell us how a child’s body is supporting the visual work of school. They are not a treatment for dyslexia, ADHD or a learning disability, and we never promise that integrating a reflex will change a reading score.

Where vision fits

Early movement and eye teaming develop over the same stretch of infancy. The American Optometric Association puts the start of three-dimensional vision at around the fifth month, describes the crawling most babies begin near 8 months as helping to develop eye-hand-foot-body coordination, and expects eye-hand coordination and depth perception to be well developed by age 2 (American Optometric Association). We follow that overlap in The Intriguing Connection Between Primitive Reflexes and Vision and on our primitive reflexes page, and set out the wider picture of infant visual development in What Can My Baby See?. The senses come next, in Learning to Learn Part 3.

If your child’s posture, handwriting or attention looks more like Student B than Student A, an evaluation is the sensible next step. Learn about our developmental vision evaluations or Schedule an evaluation.