Like the knee jerk reflex, the<unk>  is an example of a reflex mediated by a reflex arc—a neural pathway which passes via the spinal column but not through the brain. As a consequence, the movement is possible in brain-dead patients whose organs have been kept functioning by life-support machines, precluding the use of complex involuntary motions as a test for brain activity. It has been suggested by neurologists studying the phenomenon that increased awareness of this and similar reflexes "may prevent delays in brain-dead diagnosis and misinterpretations." The reflex is often preceded by slight shivering motions of the patient's arms, or the appearance of goose bumps on the arms and torso. The arms then begin to flex at the elbows before lifting to be held above the sternum. They are often brought from here towards the neck or chin and touch or cross over. Short exhalations have also been observed coinciding with the action.
Lazarus sign
Froment's sign
Munson's sign
Schwartz sign
Palla's sign
Amsler sign
Larrey's sign
Dahl's sign