Raena Morgan: Dr. Hajal, a silly question. Can you sleep with one eye open? Dr. Rizan Hajal: But I do find this question about some people don't close their eyelids all the way. But that has to do with the shape of their face and the purpose of it is to have your eyelids relaxed all the way so it doesn't really close. Its not a big thing but in human beings no, you would have to be awake. We know this is tremendous research showed in reptiles and in birds they do sleep with half their brain and the other half is still awake and including fish and dolphin for instance, the mammal fish, they actually sleep with one half of their brain asleep and the other half still awake and we think it may have to do with, they have to always be watching for predators, including at night. So they rest one half of the brain and then the other time they would rest the other half of the brain. It's amazing research that's going on right now. Raena Morgan: That is. So they sleep with one half of their brain awake. Dr. Rizan Hajal: Exactly. Raena Morgan: But humans need to close both their eyes. Dr. Rizan Hajal: No, I think. They sleep on both eyes, absolutely. Raena Morgan: Thank you Dr. Hajal.