It was a controlled experiment, as Clayton went out for a drive with a Virginia Tech research team after staying awake for 24 hours.
The specially designed car was able to track Clayton's eyes and head positioning, and had an event recorder, along with a brake on the passenger's side just in case he dozed off.
After just 15-20 minutes on the road, he was already having trouble keeping his speed at 35 mph. Over the course of an hour and 10 minutes, the research team recorded 24 instances in which he displayed diminished driving ability.
Drowsy driving caused 1,550 deaths and more than 40,000 injuries last year. Sixty percent of Americans admit to drowsy driving on a daily basis.
Watch the full, eye-opening segment above.