David Blaine is terrified his new sleep deprivation stunt will leave him permanently brain damaged. The illusionist has been undergoing strenuous physical workouts in order to prepare himself for the feat of staying awake for a record 12 days. And he admits the obsessive exercising is down to a fear of destroying his brain. Speaking at the New York Premiere of I Am Legend on Tuesday (11Dec07) Blaine - who will embark on the challenge in May (08) - says, "I'm going for the world record. I need to be in good shape for this. "And yes. I am worried that this will cause some serious damage. That's why I'm working out so hard."