Occasionally, brain-dead patients make movements, owing to the fact that the spinal reflexes are still intact. The most complex, and presumably the most terrifying, is called the Lazarus Sign. It is where the brain-dead patient extends their arms and crosses them over their chest – Egyptian mummy style.
About 20% to 40% of brain dead patients can show spontaneous movements particularly when the body is pricked with sharp objects.
While these movements are usually brief twitches, occasionally the movements can be in an extended sequence, as reported in this 1992 Journal of Neurosurgery case study about a 67-year-old lady who died from a brain haemorrhage.
At 11:15 am on February 20, brain death was declared and consent for final respirator removal was obtained from the patient’s family. The possibility of the appearance of Lazarus’ sign was explained to the family, and a video recording was made.
Five minutes after respirator removal, respiratory-like movements occurred three times; both shoulders adducted and slow cough like movements were identified. Lazarus’ sign immediately followed these respiratory-like movements. The forearms were pronated and the wrist joints extended bilaterally. Fingers on the left hand were extended, but those on the right were flexed as if grasping. Subsequently, flexion and extension in the knee and foot joints were repeatedly observed. Slow supination of both feet occurred. Finally, the left forearm was adducted to the side of the body, and the right hand pronated.
The movements continued for about 3.5 minutes, during which time blood pressure was 46/35 mm Hg and pulse rate was about 90 beats/min with a regular sinus rhythm. Cardiac arrest occurred at 11:35 am.
Link to PubMed entry for case study.
Link to brief popular article on Lazarus sign.
Mind Hacks 
Fascinating! And so, of course, it is not that the brain dead patients make movements like a resurrected Egyptian mummy (or a Vampire, or a Zombie, which just raises its arms but doesn’t get to the crossing stage) — probably our cultural traditions about what these mythical living dead do are informed by rare experiences of the Lazarus Sign in the past. Possibility?