The stepping reflex is an innate alternating leg movement pattern that can be elicited in newborns and infants when they are held upright with their feet touching a flat surface [1][2]. When the balls of the feet contact the surface, it triggers stepping motions of flexion and extension in the legs [3].

This reflex emerges around 2-3 weeks after birth, peaks at 2-3 months, and integrates into voluntary steps by 3-5 months [1][4]. It allows infants to make stepping motions before they can walk voluntarily. The reflex pathways involve sensory input from the limbs signaling spinal central pattern generators, which rhythmically activate flexor and extensor motor neurons [3][5].

Vestibular and tactile inputs help entrain the stepping to maintain balance [2][6]. The reflex diminishes as corticospinal projections develop and voluntary control of stepping emerges. Exaggeration of the reflex beyond 3-5 months can indicate corticospinal tract dysfunction [1][4]. Overall, this reflex demonstrates the early capacity for rhythmic reciprocal leg motions that form the foundation for later voluntary walking.