Evaluating Primitive Reflexes in Early Childhood as a Potential Biomarker for
Developmental Disabilities
Gerry Leisman and Robert Melillo
This article was originally published in the Journal of Paediatrics and Child Health. It is published here under a Creative Commons license and with the kind permission of the authors.
Abstract
We aim to understand better the significance of retained primitive reflexes( RPRs) and examine the effect of RPRs in children, adolescents, and adults, focusing on autism spectrum disorder( ASD) and other neurodevelopmental conditions, as well as examine a basis for future treatment alternatives. We included a history section to better recognise the way that the scientific and medical communities have studied and understood the importance of RPRs. We review findings indicating that aspects of these disorders are related to the presence of functional disconnectivities related to a cortical maturational effect on neuronal networks. Cortical maturational delay within specific networks may lead to enhanced growth and maturation in other networks, resulting in asynchronous development and inconsistency in functional skills. There has been reported an overconnectivity of short-range, more immature connections and an underconnectivity of long-range, more mature connectivities. We review the relationship between motor and cognitive impairments and RPRs. A crucial conclusion will be that inhibiting these RPRs is representative of treatment targets.
1. Primitive Reflexes: What Are They, and What Is the Controversy?
Primitive reflexes( PR) are neonatal motor and sensory reflexes. Many are present in utero [ 1 ] to assist the infant in“ birthing itself” [ 2 ]. The major role of PRs is to enable the neonate and infant to move and respond to its surroundings before maturation of the motor cortex. The infant needs to feed, move, obtain nourishment, receive protection, and orient to people and objects to stimulate its senses and muscles, thereby generating motor and sensory feedback to activate genes at a foundational level essential for bottom-up brain development [ 3 ]. The regulation of PRs originates from several brainstem areas [ 2, 3 ]. The medulla ' s lower reflexes are thought to be the first to activate, succeeded by reflex regulation linked to the mesencephalon and pons [ 4 ].
216 | vol31 | no4 | AJNM