Chronic All-Nighters?

"When you're chronically drunk, you can't tell when you're drunk. If you're chronically sleep deprived, you can't tell when you're sleepy. You lose the ability to detect how tired you are. It's not unusual to fall asleep behind the wheel," said Dr. David Schulman, the current medical director of the Emory Clinic Sleep Disorders Laboratory.

Sleepiness, like alcohol, slows reaction time, impairs  judgment, and decreases awareness. All these significantly increases the risk of a crash. Source

Most of us would like to think we'd pull over if we were too tired. But most of the symptoms of being too tired are difficult to notice, particularly when sleep deprived. We react to sleep deprivation long before we actually fall asleep at the wheel. So, how many of these things have happened to you behind the wheel?

• Difficulty focusing, frequent blinking, or heavy eyelids
  
• Daydreaming; wandering/disconnected thoughts
  
• Trouble remembering the last few miles driven; missing exits or traffic signs
  
• Yawning repeatedly or rubbing your eyes
  
• Trouble keeping your head up
  
• Drifting from your lane, tailgating, or hitting a shoulder rumble strip
  
• Feeling restless and irritable

Source: National Sleep Foundation

how anti-sleep alarms work