Primitive Reflexes and Their Role in Nervous System Development

Primitive reflexes form the foundation of the human nervous system, acting as building blocks for complex motor and cognitive functions. These automatic, involuntary movements present at birth gradually integrate as the child matures. Controlled by cranial nerves in the brainstem, these reflexes establish a balance between the parasympathetic and sympathetic nervous systems, supporting motor movement, decision-making, and emotional regulation. Cranial nerves reside in the brainstem, a more primitive part of the brain, and are resource-intensive, demanding oxygen, glucose, and yin. When reactive, they block vagal nerve signals, leaving the body in a heightened state of arousal that flood the brain with stress hormones along the HPA axis.

Integrating Movement and Emotional Health- Developing the Limbic System

Primitive reflexes evolve into postural reflexes, shaping the myofascial patterns as children grow. The cranial nerves, originating in the more primitive regions of the cervical spine and brainstem, regulate these reflexes. They play a critical role in early development by directing movement patterns that support higher-order functions like walking, running, and fine motor function in the fingers. The cranial nerves integrate into the central nervous system, regulate the developing middle jiao, and coordinate the body's fight-or-flight response. These reflexes also contribute to the development of the limbic system, the central hub of our emotional brain. Infants often experience movements and external stimuli as life-threatening. Each developmental milestone, such as achieving head control, or sitting involves exploring movement, biochemical self-regulation, and establishing new vagal pathways to ensure a parasympathetically neutral environment.

The Impact on Children's Development: Socialization and Sensory Overload

Post-pandemic, many school teachers reported that children appeared stunted in their development, lacking proper socialization. Socialization is a higher-order function of the autonomic nervous system, dealing with primitive reactions related to social engagement. The trauma of not attending school during formative years was significant, but the greater trauma was the sensory overload from excessive screen time before their brains were ready.[1] As I mentioned, the brain will begin to ignore and then diminish afferent sensory pathways in an attempt to reduce sensory input. A developing child has not finished their limbic or emotional regulation, which is part of the educational process. In an attempt to reduce their own overwhelm, children will first resist and then refuse subjects that overwhelm their autonomic nervous system (ANS). While it looks like defiant behavior, many times it is self-preservation.