Hyperreflexia refers to the expansion of the reflex range during deep reflexes compared to normal. Deep reflexes are most commonly radial periosteal reflexes and knee reflexes. For example, the radial membrane reflex is normally examined by tapping on the lateral side of the radius, the radial membrane, and the patient will experience muscle contraction movements in the upper extremity. If the reflex contraction occurs when the non-radial membrane area, such as the tendon area or the muscle area, is tapped, it is called hyperreflexia. For example, if the knee reflex is tapped on the quadriceps tendon below the kneecap, and if the reflex is tapped on the front of the tibia, and if the reflex is also tapped on the quadriceps muscle, it is called hyperreflexia. Hyperreflexia is often accompanied by active reflexes, the latter of which refers to an expansion of the reflexes, that is, an increase in the strength and range of muscle contractions.