BIOLOGY | MEDICAL | HEALTH on Instagram: "The Babinski sign is a neurological reflex commonly seen in babies under one year old. It occurs due to the immaturity of the corticospinal tract, the nerve pathway that connects the brain to the spinal cord. When the sole of a baby’s foot is gently stroked, the big toe moves upward while the other toes fan out — a curious response that’s actually a healthy sign of neurological development. As the central nervous system matures, typically by the end of t