Primitive Reflexes & Brain Growth: What Every Parent Should Know
Based on:
Evaluating Primitive Reflexes in Early Childhood as a Potential Biomarker for Developmental Disabilities
Authors: Gerry Leisman & Robert Melillo
Accepted: March 30, 2025
Published in: Journal of Paediatrics and Child Health
Access: https://doi.org/10.1111/jpc.70053
Why This Study Matters
Many parents exploring developmental functional neurology and the Melillo Method have heard of primitive reflexes (PRs)—but what actually are they? Why do babies have them in the first place? What happens if they don't go away?
This 2025 paper explores those exact questions—and offers a fascinating window into how these early reflexes support the developing brain, and why their persistence can interfere with everything from learning to regulation and immune function.
Primitive reflexes are not just about movement—they’re part of a critical chain reaction that builds your child’s brain from the bottom up.
What the Researchers Did
The authors reviewed decades of neuroscience literature on primitive reflexes, motor development, and brain maturation, making the case that unintegrated reflexes (RPRs) can serve as early biomarkers for developmental disorders like ASD, ADHD, and dyslexia.
They explain exactly why these reflexes exist, what they do in infancy, how they should integrate—and what happens if they don’t.
What They Found
Why primitive reflexes exist:
Primitive reflexes are survival reflexes. They allow a newborn—who has no volitional motor control—to feed, move, seek comfort, and orient to people and sensory input. They generate essential motor and sensory feedback to the brainstem, which activates genes and promotes the earliest stages of brain development.
How they integrate:
As the infant moves, PRs stimulate sensory pathways that promote neuroplasticity, helping higher brain areas grow—from the pons and midbrain all the way to the neocortex. Over time, top-down control from the maturing frontal lobes inhibits these reflexes. This transition allows more complex, voluntary, and socially adaptive behaviours to emerge.
What happens when they don’t integrate:
If primitive reflexes are not inhibited in the first year, they may persist—and continue to interfere with brain development. The result can be global dysregulation across the nervous, immune, endocrine, and autonomic systems.
This persistent “bottom-up noise” can prevent the brain from achieving full maturity and integration.
Why It’s Relevant for Families
If your child skipped tummy time or crawling, struggles with balance, clumsiness, coordination, or still finds catching, cycling, or handwriting hard—primitive reflexes could be part of the picture.
The authors highlight strong correlations between RPRs and:
· ADHD (with markedly greater prevalence of Moro and Galant reflexes)
· Dyslexia (predictive links to ATNR, palmar reflexes, and neck retraction)
· Autism spectrum disorders (linked to delays in motor cortical maturation, social engagement, and cognition)
· Clumsiness and DCD (linked to immature motor responses and cerebellar involvement)
These aren’t just isolated reflexes—they are signs of immature integration across the brain and body.
How I Use This Insight at Flourishing Brains
Primitive reflexes are not routinely checked—but they absolutely should be. In our practice, they’re one of the first things I assess, because they give us a clear window into your child’s neurological maturity.
We don’t just treat symptoms—we work with the underlying brain patterns that affect everything from posture to behaviour.
Once we understand which reflexes are still active, we can begin a process of integration using:
· Gentle, targeted movement and sensory stimulation
· Brain balance exercises
· Supportive therapies like low-level laser to help the brain heal and rewire
These tools help the nervous system shift from “stuck” to adaptable—making space for your child’s potential to unfold.
Want to Keep Learning?
If this article interested you, I’d love to support your journey.
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