There was a guy in my class that would literally "fall" asleep in the midst of conversation. I always thought it was fascinating. "How can you just fall asleep like that. How tired can you possibly be". As I progressed through my biomedical engineering career, I was like oooooooo. Makes sense! Good post. Hive account@winstonalden I just followed you. There is a lab by lab that studies this also.