What Is the Babinski Reflex?

Medically Reviewed by Dan Brennan, MD on February 15, 2024
3 min read

The Babinski reflex — also called the plantar reflex — is a response to stimulation of the bottom of the foot. It can help doctors evaluate a neurological problem in people over age 2. If your child has this reflex and doesn’t show any other signs of neurological problems, however, there’s probably no need to worry.

The Babinski reflex may show a problem in the corticospinal tract — or CST. CST is a neural pathway that goes from your brain to your spinal cord and helps you control your movements. It is routinely performed as part of a neurological exam.

The Babinski test is used to assess for problems in the CST, and a positive Babinski reflex test may mean that you have a neurological problem.

Joseph Babinski first described this test in 1899. He was the protegé and student of the doctor Jean-Martin Charcot, whose work led to the identification of amyotrophic lateral sclerosis — or ALS. Even though it is over 100 years old, the Babinski reflex test is still an important and widely used neurological test. 

The Babinski test can be done quickly with basic tools. Also, doctors can do this test on you when you’re awake, asleep, or even in a coma. They can also do it if you are awake but can’t follow directions for any reason.

To perform the Babinski test, your doctor will use their finger or a tool like a stick or a hammer to stimulate the bottom of your foot. They’ll run it firmly from the outer edge of the foot at the heel to the bottom of the big toe.

In older children and adults without neurological problems, the foot will remain still, or the toes may curl downward during the Babinski test. If you do have a Babinski sign, your big toe will bend back, and your other four toes will spread out like a fan. 

You might feel a tickle or slightly uncomfortable sensation during the test. Sometimes, people are particularly sensitive and tense up or withdraw because it feels ticklish or uncomfortable. If you feel too ticklish during this test, your doctor will do a different test.

It can sometimes be hard for your doctor to tell the difference between a withdrawal response and a Babinski sign. However, a withdrawal response looks different each time, but the Babinski reflex looks quite similar each time. If your doctor has trouble telling the difference, they’ll do one of the other tests that are supposed to show the same response.

The only time your doctor shouldn’t do the Babinski test is when you have an injury or lesions on the bottom of your feet. If you’re missing your big toe, your doctor will not be able to evaluate the test results properly. They will use a different test in that case.

If you do have an injury on the bottom of your foot, there are other tests your doctor can perform to test for the same response:

  • Chaddock reflex. Your doctor will use a blunt instrument like the opposite end of a reflex hammer and run it along the outer edge of the top of the foot instead of the bottom. They’ll go from just under the ankle up the entire foot.
  • Gordon reflex. Your doctor will ask the child to lie down face up. They’ll then lift the child’s leg and squeeze their calf muscle to look for the Gordon reflex.
  • Oppenheim reflex. Your doctor will run a firm tool along the tibia — the bone that you can feel on the front of your calf.

Some people have an exaggerated or extreme Babinski reflex when they’re in a coma — in some cases, they not only pull back the big toe and fan out the other toes but also bend the knee. These three movements confirm that there’s been a more serious neurological injury.

Your doctor may use this test if they suspect a neurological problem. However, it can be especially useful in emergency situations like a stroke or spinal cord injury. Doctors perform the Babinski test for a quick check on what may be happening before ordering more complex diagnostic tests.