Drivers might not realize how fatigued they are. Other motorists might experience micro-sleep, which are short periods of inattention that can last about four to five seconds. This is all the time that is needed for a vehicle to travel 100 yards or the length of a football field. Signs of fatigued driving include drifting in and out of lanes, missing exists, and not remembering the past few miles driven. Repeatedly running off the road and frequent yawning and blinking are also signs of drowsiness behind the wheel. Certain medications can create feelings of drowsiness too.