Table of ContentsView AllTable of ContentsWhat Is a Reflex?Normal vs. PathologicalStrange ReflexesFrequently Asked Questions
Table of ContentsView All
View All
Table of Contents
What Is a Reflex?
Normal vs. Pathological
Strange Reflexes
Frequently Asked Questions
A reflex is an automatic or involuntary body movement. Thenervous systemtells your body to kick a leg, curl the toes, or move in some other way because something has touched you or alerted your senses. Some reflexes, like pulling your hand away from a hot pan, are normal. Other automatic movements are not normal and may be a sign of a medical condition.
This article explains the differences between normal and abnormal reflexes and explains how doctors check for specific types of reflexes that can point to health issues.
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Reflexes are movements that occur automatically, sometimes without the brain even being involved. They let your body carry out essential actions like standing upright without you having to think about them.
The most familiar reflex is straightening your knee when a doctor taps on the tendon below your kneecap with a reflex hammer. A stimulus (the hammer) causes a signal to be sent via a sensory nerve to the spinal cord. From the spinal cord, a response is immediately sent back via a motor nerve, which results in the kick.
This communication that goes from a sensory nerve to the spinal cord and on to a motor nerve without involving the brain is known as a reflex arc.
Any muscle can be tested for a reflex as long as there’s a tendon that can be acted on with a stimulus.
Normal vs. Abnormal Reflexes
Many reflexes are normal. For example, the knee jerk is a normal reflex and the absence of this reflex would be considered abnormal.
Having an unusual reflex reaction could be a sign of disease. However, abnormal reflexes also occur fairly often in healthy people who don’t have anyneurologicaldisorders or problems with their nervous system.If there are no clear issues with the nervous system that would cause abnormal reflexes, doctors consider other symptoms, tests, or observations to determine what’s causing the problem.
Pathological Reflexes
Newborns display a number of unique reflexes, but babies outgrow these. If reflexes that are specific to babies occur in adults, they’re consideredpathological, which means they’re not normal and may point to an underlying condition.
RecapA reflex is an automatic physical reaction to stimuli, which could include a noise, physical sensation, taste, sight, or smell. Whether or not your reflexes are normal may depend on your age or circumstances. Unusual reflexes, though, could be a sign of a neurological (nervous system) disorder or other health condition.
Recap
A reflex is an automatic physical reaction to stimuli, which could include a noise, physical sensation, taste, sight, or smell. Whether or not your reflexes are normal may depend on your age or circumstances. Unusual reflexes, though, could be a sign of a neurological (nervous system) disorder or other health condition.
The body is capable of many types of reflexes. The following are some of the lesser-known and seemingly strange, but totally normal, body reflexes.
The Babinski Reflex
TheBabinskireflex is one of the most common reflexes that a neurologist may test for. In this exam, a neurologist scratches the bottom of your foot with something irritating.
In an adult, the toes will normally curl down. Yet typically in children age 2 and under, the toes instead turn up and fan out. Adults may have the same reaction as babies. When that happens, it may be a sign of astroke, a tumor, inflammation around the brain, or a spinal cord injury.
The Snout Reflex
If an adult has the same reflex response when their upper lip is tapped, it’s considered abnormal and may indicate that the frontal lobes of the brain are damaged. This type of problem can result fromfrontal lobe head traumaor afrontal lobe stroke.
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The Glabellar Reflex (Myerson’s Sign)
The area of the forehead above the nose and between the eyes is called theglabella. Most people automatically blink when they’re tapped on the glabella.
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The Palmomental Reflex
Along with the snout reflex, the palmomental reflex in adults indicates that there may be damage to the frontal lobes of the brain. However, healthy people without brain damage may also display palmomental reflexes.
The Anal Reflex
The anal reflex may also be called the anal wink, theperinealreflex, or theanocutaneousreflex.
It’s a normal reflex in which the anal sphincter, the ring of muscles around the bottom of your anus, tightens when something irritating stimulates the area. This can include something as simple as the skin around the anus being stroked.
If your muscles don’t tighten in response to a stimulus, it may mean that you have spinal cord damage that is affecting the main nerve in your pelvis, thepudendalnerve.
The Cremasteric Reflex
Thecremastericreflex is a response to being lightly stroked on the inside of the thigh. In men, this causes the cremaster muscle to contract and the testes to elevate.
This reflex can disappear for many reasons. Damage to the brain or spinal cord may result in a loss of the cremasteric reflex. Problems that aren’t related to the nervous system such as a twisting of the testicles (known astesticular torsion) can cause it as well.
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Clonus
Clonus may be related to upper motor neuron disorders and mood issues such as:
Hoffman’s Reflex
A Hoffman’s reflex that is stronger on one side of the body often signifies an injury or abnormality in the spinal cord around the neck or upper back.
Hoffman’s reflex could be due to a tumor or a number of other conditions including:
Imaging scans are often used when trying to diagnose a spinal cord problem. However, a physical exam that checks for Hoffman’s reflex can also be used to help identify early spinal cord dysfunction.
Summary
Evaluating your reflexes can give doctors valuable clues to your health. While some areas such as the knee and the foot are common places to test, there are many other less common areas where doctors can check your reflexes.
Testing reflexes may be the first step to diagnosing a spinal cord injury or neurological disorder as doctors observe how your nervous system responds to different stimuli. If you don’t respond as you should to certain tests, or if you have excessive twitching, your doctor will send you for additional tests to see if there are underlying illnesses or an injury.
If your knee doesn’t kick out when the patellar tendon is tapped, it’s called Westphal’s sign. The lack of a reaction is usually a sign of neurological problems specifically related to the peripheral nervous system.A wide range of disorders can affect the peripheral nervous system, including inherited degenerative diseases, autoimmune diseases, alcohol abuse, and cancer.Learn MoreUnderstanding the Peripheral Nervous System
If your knee doesn’t kick out when the patellar tendon is tapped, it’s called Westphal’s sign. The lack of a reaction is usually a sign of neurological problems specifically related to the peripheral nervous system.A wide range of disorders can affect the peripheral nervous system, including inherited degenerative diseases, autoimmune diseases, alcohol abuse, and cancer.
Learn MoreUnderstanding the Peripheral Nervous System
Learn MoreHealth and Development of Premature Infants
This may be due to hyperactive reflexes, a condition in which muscles move or twitch in response to little or seemingly no stimuli. The most common cause is a spinal cord injury.It may also be the result of other problems such as a thyroid condition, multiple sclerosis, or electrolyte imbalance.Learn MoreGuide to Multiple Sclerosis
This may be due to hyperactive reflexes, a condition in which muscles move or twitch in response to little or seemingly no stimuli. The most common cause is a spinal cord injury.It may also be the result of other problems such as a thyroid condition, multiple sclerosis, or electrolyte imbalance.
Learn MoreGuide to Multiple Sclerosis
12 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Sanders RD, Gillig PM.Reflexes in psychiatry.Innovations in clinical neuroscience. 2011;8(4):24-9.MedlinePlus.Babinski reflex.Hamedani AG, Gold DR.Eyelid dysfunction in neurodegenerative, neurogenetic, and neurometabolic disease.Front Neurol. 2017;8. doi:10.3389/fneur.2017.00329Gabelle A, Gutierrez LA, Dartigues JF, Ritchie K, Touchon J, Berr C.Palmomental reflex a relevant sign in early Alzheimer’s disease diagnosis?Journal of Alzheimer’s disease: JAD. 2016;49(4):1135-41. doi:10.3233/JAD-150436Reeves A., Swenson, R.Reflex evaluation. 5th ed.Disorders of the nervous system: A primer. Hanover, NH: Dartmouth College.Mellick LB, Al-Dhahir MA.Cremasteric reflex. In:StatPearls. StatPearls Publishing; 2024.Kasahata.Bilateral finger jerks as a useful sign for diagnosis of cervical compressive myelopathy.J Neurol Res. Published online 2011. doi:10.4021/jnr15wBhimani R, Anderson L.Clinical understanding of spasticity: Implications for practice.Rehabilitation Research and Practice. 2014;2014:1-10. doi:10.1155/2014/279175Tu J, Vargas Castillo J, Das A, Diwan AD.Degenerative cervical myelopathy: Insights into its pathobiology and molecular mechanisms.Journal of Clinical Medicine. 2021;10(6):1214. doi:10.3390%2Fjcm10061214Jakobi J, Kohn S, Kuzyk S and Fedorov A.When kicking the doctor is good—A simple reflex.Frontiers for Young Minds.2017;5:10. doi:10.3389/frym.2017.00010Mount Sinai Medical Center.Infant reflexes.Xu D, Guo X, Yang CY, Zhang LQ.Assessment of hyperactive reflexes in patients with spinal cord injury.BioMed Research International. 2015;2015:e149875. doi:10.1155%2F2015%2F149875
12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Sanders RD, Gillig PM.Reflexes in psychiatry.Innovations in clinical neuroscience. 2011;8(4):24-9.MedlinePlus.Babinski reflex.Hamedani AG, Gold DR.Eyelid dysfunction in neurodegenerative, neurogenetic, and neurometabolic disease.Front Neurol. 2017;8. doi:10.3389/fneur.2017.00329Gabelle A, Gutierrez LA, Dartigues JF, Ritchie K, Touchon J, Berr C.Palmomental reflex a relevant sign in early Alzheimer’s disease diagnosis?Journal of Alzheimer’s disease: JAD. 2016;49(4):1135-41. doi:10.3233/JAD-150436Reeves A., Swenson, R.Reflex evaluation. 5th ed.Disorders of the nervous system: A primer. Hanover, NH: Dartmouth College.Mellick LB, Al-Dhahir MA.Cremasteric reflex. In:StatPearls. StatPearls Publishing; 2024.Kasahata.Bilateral finger jerks as a useful sign for diagnosis of cervical compressive myelopathy.J Neurol Res. Published online 2011. doi:10.4021/jnr15wBhimani R, Anderson L.Clinical understanding of spasticity: Implications for practice.Rehabilitation Research and Practice. 2014;2014:1-10. doi:10.1155/2014/279175Tu J, Vargas Castillo J, Das A, Diwan AD.Degenerative cervical myelopathy: Insights into its pathobiology and molecular mechanisms.Journal of Clinical Medicine. 2021;10(6):1214. doi:10.3390%2Fjcm10061214Jakobi J, Kohn S, Kuzyk S and Fedorov A.When kicking the doctor is good—A simple reflex.Frontiers for Young Minds.2017;5:10. doi:10.3389/frym.2017.00010Mount Sinai Medical Center.Infant reflexes.Xu D, Guo X, Yang CY, Zhang LQ.Assessment of hyperactive reflexes in patients with spinal cord injury.BioMed Research International. 2015;2015:e149875. doi:10.1155%2F2015%2F149875
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Sanders RD, Gillig PM.Reflexes in psychiatry.Innovations in clinical neuroscience. 2011;8(4):24-9.MedlinePlus.Babinski reflex.Hamedani AG, Gold DR.Eyelid dysfunction in neurodegenerative, neurogenetic, and neurometabolic disease.Front Neurol. 2017;8. doi:10.3389/fneur.2017.00329Gabelle A, Gutierrez LA, Dartigues JF, Ritchie K, Touchon J, Berr C.Palmomental reflex a relevant sign in early Alzheimer’s disease diagnosis?Journal of Alzheimer’s disease: JAD. 2016;49(4):1135-41. doi:10.3233/JAD-150436Reeves A., Swenson, R.Reflex evaluation. 5th ed.Disorders of the nervous system: A primer. Hanover, NH: Dartmouth College.Mellick LB, Al-Dhahir MA.Cremasteric reflex. In:StatPearls. StatPearls Publishing; 2024.Kasahata.Bilateral finger jerks as a useful sign for diagnosis of cervical compressive myelopathy.J Neurol Res. Published online 2011. doi:10.4021/jnr15wBhimani R, Anderson L.Clinical understanding of spasticity: Implications for practice.Rehabilitation Research and Practice. 2014;2014:1-10. doi:10.1155/2014/279175Tu J, Vargas Castillo J, Das A, Diwan AD.Degenerative cervical myelopathy: Insights into its pathobiology and molecular mechanisms.Journal of Clinical Medicine. 2021;10(6):1214. doi:10.3390%2Fjcm10061214Jakobi J, Kohn S, Kuzyk S and Fedorov A.When kicking the doctor is good—A simple reflex.Frontiers for Young Minds.2017;5:10. doi:10.3389/frym.2017.00010Mount Sinai Medical Center.Infant reflexes.Xu D, Guo X, Yang CY, Zhang LQ.Assessment of hyperactive reflexes in patients with spinal cord injury.BioMed Research International. 2015;2015:e149875. doi:10.1155%2F2015%2F149875
Sanders RD, Gillig PM.Reflexes in psychiatry.Innovations in clinical neuroscience. 2011;8(4):24-9.
MedlinePlus.Babinski reflex.
Hamedani AG, Gold DR.Eyelid dysfunction in neurodegenerative, neurogenetic, and neurometabolic disease.Front Neurol. 2017;8. doi:10.3389/fneur.2017.00329
Gabelle A, Gutierrez LA, Dartigues JF, Ritchie K, Touchon J, Berr C.Palmomental reflex a relevant sign in early Alzheimer’s disease diagnosis?Journal of Alzheimer’s disease: JAD. 2016;49(4):1135-41. doi:10.3233/JAD-150436
Reeves A., Swenson, R.Reflex evaluation. 5th ed.Disorders of the nervous system: A primer. Hanover, NH: Dartmouth College.
Mellick LB, Al-Dhahir MA.Cremasteric reflex. In:StatPearls. StatPearls Publishing; 2024.
Kasahata.Bilateral finger jerks as a useful sign for diagnosis of cervical compressive myelopathy.J Neurol Res. Published online 2011. doi:10.4021/jnr15w
Bhimani R, Anderson L.Clinical understanding of spasticity: Implications for practice.Rehabilitation Research and Practice. 2014;2014:1-10. doi:10.1155/2014/279175
Tu J, Vargas Castillo J, Das A, Diwan AD.Degenerative cervical myelopathy: Insights into its pathobiology and molecular mechanisms.Journal of Clinical Medicine. 2021;10(6):1214. doi:10.3390%2Fjcm10061214
Jakobi J, Kohn S, Kuzyk S and Fedorov A.When kicking the doctor is good—A simple reflex.Frontiers for Young Minds.2017;5:10. doi:10.3389/frym.2017.00010
Mount Sinai Medical Center.Infant reflexes.
Xu D, Guo X, Yang CY, Zhang LQ.Assessment of hyperactive reflexes in patients with spinal cord injury.BioMed Research International. 2015;2015:e149875. doi:10.1155%2F2015%2F149875
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