A spokesman at Jerusalem's Haddasah Hospital said Sharon blinked both eyes, but the medical significance of this is not clear.
Sharon is still listed in critical but stable condition. However, outside experts question his ability to recover because he has failed to respond to efforts to awaken him from a medically-induced coma.
Yesterday, the 77-year-old Israeli leader underwent a tracheotomy that doctors hoped would help wean him off a respirator that has been helping him breathe since the stroke.
He also has been taken off sedatives.
(AP, Reuters)