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What is a Motor Reflex?

Troy Holmes
Troy Holmes

Reflexes are an involuntary response or motion that occurs in humans based on conditions or stimulus response. A motor reflex is something that happens with the joints of the human body when specific pressure points are stimulated. The most common reflexes reviewed by doctors involve the ankle, knee, and elbow. They are typically tested with a special reflex tendon hammer.

The knee motor reflex test is one of the most common reflex tests. This is accomplished by having a doctor hit the pressure point below the kneecap with a reflex hammer. If the reflexes are working properly, the knee should involuntarily rise slightly with the tapping sensation of the pressure point.

The ankle jerk reflex test is an example of an automatic motor reflex test.
The ankle jerk reflex test is an example of an automatic motor reflex test.

Most toddlers go through a Nero exam when they are between two and three years of age. This exam is meant to test the reflexes of the arms, knees, and ankles. Additional testing is typically necessary if the reflex testing shows abnormalities. This could include special neurological tests designed to determine underling reflex issues.

A motor reflex is a involuntary response to stimulus. This automatic reflex is due to a special neural path that is connected to pressure points of the body. When these points are pressed, the muscles of the body will contract or extend, depending on the muscle being stimulated.

The bicep reflex test is an example of a muscle stretch reflex test. This reflex is exercised by hitting the lower area of the bicep tendon with a tendon hammer. If the reflex is working properly, the muscle should contract, causing the arm to close.

A reflex hammer is commonly used in a knee motor reflex test.
A reflex hammer is commonly used in a knee motor reflex test.

There are many exercises designed to improve the reflexes of children and adults. These exercises stimulate muscle and brain neurological pathways. A good exercise routine and sensory motor rehabilitation can also greatly assist in the improvement of motor reflexes in humans.

The ankle jerk reflex test is another example of an automatic motor reflex test. This test is completed by tapping the back of the ankle tendon above the foot. If the reflex is working properly, the foot should move in an open jerking motion.

Most motor reflexes tend to weaken with age. This is often seen in the ankle jerk test in adults older than 60. It is not known what causes the decrease in reflexes with age, but exercise and a healthy lifestyle may prolong these automatic responses.

Discussion Comments

stoneMason

@SteamLouis-- I agree with you, motor reflexes can help doctors diagnose problems. But sometimes, the presence of the reflex is a problem rather then its absence. For example, a strong jaw jerk reflex is a sign of a problem with the upper motor nerves.

SteamLouis

@ddljohn-- It is important to test motor reflexes in children regularly. Since they are still growing and developing, doctors will want to make sure that their neurological reflexes are developing properly as well.

For adults, checking various motor reflexes may not be necessary during every check up. But they are absolutely necessary if an individual has symptoms that suggest problems with the nerves. A simple motor reflex test in that part of the body can tell the doctor the presence and extent of the problem so that further testing can be done.

Although motor reflex testing seems very simple, almost like a game, they have great significance as far as physical symptoms are concerned.

ddljohn

My general practitioner loves testing motor reflexes. Every time I go in for a routine checkup or something like the flu, he gives me the motor reflex tests. I tell him that he did it last time but he does it again. I don't know much about medicine, but I don't really see the point of testing these during every doctor's visit. If someone's motor reflexes are working fine, they will probably stay that way right?

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    • The ankle jerk reflex test is an example of an automatic motor reflex test.
      By: WavebreakMediaMicro
      The ankle jerk reflex test is an example of an automatic motor reflex test.
    • A reflex hammer is commonly used in a knee motor reflex test.
      By: nooneoui
      A reflex hammer is commonly used in a knee motor reflex test.
    • Between ages two and three, toddlers typically have a Nero exam where their reflexes are tested.
      By: jolopes
      Between ages two and three, toddlers typically have a Nero exam where their reflexes are tested.
    • The bicep reflex test is an example of a muscle stretch reflex test.
      By: Protosom
      The bicep reflex test is an example of a muscle stretch reflex test.