plantar response

physiology

Also known as: Babinski reflex, Babinski response

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Last updated

June 17, 2026

Quick Summary

The plantar response, also known as the Babinski reflex, is a neurological test. Normally, when the sole of the foot is stimulated by drawing a stick across it, the big toe curls downward. This indicates healthy central nervous system function, specifically intact pyramidal tracts.1

However, if the big toe turns upward and the other toes fan out, it suggests damage to the central nervous system, particularly the pyramidal tracts. This abnormal response is more common in infants, as their nervous systems are still developing, but it signifies a problem in adults. The muscles of the lower leg and foot are complex and involved in various movements, including those tested by the plantar response.213

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human behaviour
The newborn infant
…age; one example is the Babinski reflex, in which the infant bends his big toe upward and spreads his small toes when the outer edge of the sole of his foot is stroked.
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…age; one example is the Babinski reflex, in which the infant bends his big toe upward and spreads his small toes when the outer edge of the sole of his foot is stroked.
Read More

nervous system disease
Reflex activity
The plantar, or Babinski, response is the only abnormal reflex that is routinely detected. Normally, the big toe curls downward when the examiner draws a stick up the sole of the foot. In the presence of a corticospinal tract lesion, it curls upward instead, and the…
Read More
The plantar, or Babinski, response is the only abnormal reflex that is routinely detected. Normally, the big toe curls downward when the examiner draws a stick up the sole of the foot. In the presence of a corticospinal tract lesion, it curls upward instead, and the…
Read More