Final answer:
The stepping reflex, also known as the walking reflex, is an automatic response observed in newborn babies when held upright with their feet touching a solid surface. When the soles of their feet touch the surface, they instinctively make stepping movements as if attempting to walk.
Step-by-step explanation:
The stepping reflex is a primitive reflex observed in newborns, typically disappearing around two months of age. When a baby is held upright with their feet touching a flat surface, they demonstrate rhythmic and alternating stepping movements resembling walking. This reflexive behavior is an indication of the innate ability to take steps and is an early precursor to actual voluntary walking.
The neural pathways involved in the stepping reflex aren't fully developed at birth. However, the stimulation of the soles of the feet triggers a response from the spinal cord, prompting the leg muscles to contract and create stepping motions. This reflex is vital as it suggests the groundwork for future motor skills related to walking.
The stepping reflex's disappearance aligns with the gradual development of voluntary control over leg movements and the strengthening of neural connections. This reflex's presence at birth and subsequent disappearance is a fundamental part of the infant's neurological and motor development.