Primitive Reflexes Explained

Primitive reflexes are the built-in, involuntary movements babies are born with: the startle, the grasp, the rooting that turns a hungry baby toward a cheek touch. They normally fade on a schedule in the first months of life, and professionals read their timing as a window into the developing nervous system. If a provider mentioned a "retained reflex," here is what these are, when they fade, what DMI says, and what to ask.

What are primitive reflexes?

These are involuntary movements, controlled by the brainstem, that are present at birth. They need no thought: a touch on the palm closes the hand into a grasp, and a sudden change of head position brings on the Moro startle. Zafeiriou's review, from the Neurodevelopmental Center at Aristotle University of Thessaloniki, describes the primitive reflexes and postural reactions as "one of the earliest, simplest, and most frequently used tools among child neurologists to assess the central nervous system integrity of infants and young children."

A 2026 StatPearls review groups them by what they do:

• Feeding reflexes (rooting and sucking), which help a newborn feed.
• Protective reflexes (the Moro startle and the asymmetric tonic neck reflex), which give defensive responses.
• Grasp reflexes (palmar and plantar), which support early attachment.
• Lower-body reflexes (Babinski, stepping, and Galant), which support early motor development.

When do they fade, and what does "integration" mean?

Typical development does not keep these forever. As the brain's cortex matures and voluntary control develops, the nervous system gradually suppresses them, mostly between 4 and 6 months of age, according to the StatPearls review. This process is often called integration. There is a range of normal timing, and one lingering reflex is not a diagnosis on its own.

Persistence matters in the bigger picture. The StatPearls review says reflexes that persist beyond the expected age can signal a problem with the nervous system. The 2004 review notes that infants with cerebral palsy have been known to show persistence or a delay in the disappearance of primitive reflexes, and that in several studies, infants with five or more abnormal postural reactions went on to develop cerebral palsy or a developmental disability. That is why the review recommends checking reflexes and postural reactions together as a simple, predictive screening test for infants at risk of cerebral palsy.

What DMI says about primitive reflexes

DMI's own training organization addresses this in its clinical commentary, which opens its primitive reflexes section: "Primitive reflexes originate in the brain stem and are involuntary innate motor movements. They aid basic survival and assist a baby in learning movement. Primitive reflexes are the foundation upon which higher brain function is built." It then describes DMI practice: "With graded and repeated practice, the child becomes less reliant on primitive reflexes to move and begins incorporating new movements into their motor repertoire with improved movement quality."

DMI does not claim to erase reflexes; it describes children becoming less reliant on them as voluntary movement builds. That fits the review's picture, but it is a statement of mechanism from DMI's developers, not a measured outcome. The review dates to 2004, seventeen years before DMI was introduced in February 2021; no controlled study of DMI has been published, so no one can yet tell you from research that DMI changes reflex status. The absence of controlled research is not evidence that it doesn't work, only that the claim is untested.

What it means for your child

If a provider mentions reflexes in your child's evaluation, hear it this way: it is one clue in a full examination, most meaningful alongside how your child moves, holds their head, rolls, and reaches. One retained reflex does not diagnose anything on its own. What persistence can do is prompt a closer look, especially for cerebral palsy, alongside early-detection tools like the HINE.

The timing matters the other way too: a reflex missing when it should be present is also information, which is why this site's hypotonia guide lists absent, rather than simply reduced, reflexes among the signs that call for a workup.

For parents weighing DMI, none of this is a reason to avoid it; it even explains why a DMI therapist talks about reflexive movement, at the level of automatic, gravity-driven responses. Keep claims in proportion: a therapist can describe a mechanism, but only published, controlled research can measure whether it changes outcomes, and none exists yet.

What to ask

• Ask your pediatrician or therapist which reflexes they are checking and what they see; that tells you whether this is routine or being followed.
• Ask what persistence means for a skill: "If it's still present, what does that mean for rolling, sitting, or using both hands together?" Tie it to a milestone you can see.
• Ask a DMI provider how reflexes fit their plan: DMI's own language is becoming "less reliant on primitive reflexes," so ask how that goal will be reached and recognized.
• Ask how change will be measured: a standardized measure like the GMFM-88, milestone tracking, or home video.

What this explainer does not establish

This is a review of an assessment approach, not a treatment study. It tests no therapy, predates DMI by seventeen years, and has no controlled comparison, and the lines from DMI's website are DMI's own description of its approach, quoted so you can see its claims in its own words. None of these sources tells you whether any therapy changes reflex integration; together they give you the vocabulary to understand a provider.

Where it appears on this site

Reflexes come up in several places here. The Shoaib Sensorimotor Development Tool explainer notes that one of its domains scores whether primitive reflexes and righting reactions are integrated, including the Moro, rooting and sucking, and the tonic neck and labyrinthine reflexes. The HINE explainer covers the reflexes and reactions section, the atlantoaxial explainer quotes overactive reflexes among warning signs in Down syndrome guidance, and the hypotonia guide lists absent reflexes as a red flag for a workup.

Sources

• Zafeiriou DI. Primitive reflexes and postural reactions in the neurodevelopmental examination. Pediatric Neurology. 2004;31(1):1-8. PubMed
• Chamarthi VS, Gunasekaran V, Daley SF. Primitive Reflexes: Comprehensive Neurological Assessment Across the Lifespan. StatPearls. Treasure Island (FL): StatPearls Publishing; 2026. PubMed
• DMI Therapy. DMI Clinical Commentary, section on primitive reflexes. dmitherapy.com