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Last June, a truck driver for Wal-Mart struck a car carrying Tracy Morgan, seriously injuring the comedian and killing his close friend. According to police, the truck driver had been awake more then 24 hours at the time of the crash.
On Jan. 26, 2008, Virginia Tech University freshman Nicole Lee was killed as she returned to campus after a day of skiing with four friends when the 1999 Nissan Pathfinder they were in hit a tree head-on in West Virginia. State police said alcohol or excessive speed were not factors in the crash and that they believed the driver fell asleep at the wheel.
"There were no skid marks or [signs of] braking; [the driver] hit a tree on my sister's side of the car at full speed," said Jennifer Pearce, Nicole's older sister. "My sister was an amazing young woman full of life, and she was taken from us instantaneously." Today Nicole's family educates drivers on the dangers of drowsy driving.
Drowsy driving causes more than 100,000 crashes a year, according to the National Highway Traffic Safety Administration. DrowsyDriving.org, part of the National Sleep Foundation, says it causes an estimated 1,550 deaths and 71,000 injuries every year.
To demonstrate the danger, NBC national investigative correspondent Jeff Rossen tested his skill on a technical obstacle course at the Skip Barber Driving School in Lakeville, Connecticut. First he drove the course while rested and wide awake, pulling off tight turns and last-minute lane changes without hitting a single traffic cone.
Then Rossen went home and kept himself awake for nearly 30 hours before returning to tackle the course again. Though tired, he said, "Actually, I feel fine. I feel like this is the kind of situation that a lot of people drive in. Maybe I could too."
But this time Rossen failed the course badly, hitting traffic cones — each one simulating a crash — over and over again.
Dr. Charles Czeisler of Boston's Brigham and Women's Hospital, one of the country's leading authorities on sleep, analyzed video of Rossen's driving tests. "It's a dramatic difference," Czeisler said of the second test. "He's certainly impaired and is struggling to stay awake, and at any moment could lose that struggle."
Just a few moments of what experts call micro-sleep could be the difference between life and death, Czeisler explained. "Most people don't realize that part of the brain can be asleep while another part of the brain is awake. So you may be able to keep your foot full throttle on the accelerator and even negotiate certain turns and yet not have the judgment area of the brain engaged."
In a final test, a fatigued Rossen began driving for several miles, simulating a long highway trip. When he encountered an unexpected line of cones on his final lap, he was unable to avoid them.
"That could have been a car," Rossen said. "That could have been a person. It's scary."
Doctors warn that losing sleep for one night is the equivalent of being legally drunk. And experts say the best indicator that you're about to fall asleep at the wheel is actually having it happen: Many drivers have experienced a moment when they feel themselves nodding off, then jolt awake and get a false sense of security, once their adrenaline is going, that they're good to drive. But doctors say you're likely to nod off again within minutes.
To learn more about the effort by Nicole Lee's family to educate the public on the dangers of drowsy driving, click here.