Monday, December 26, 2011
Sleepiness During Real Driving at Night
We know that driving while sleepy is dangerous. Driving in the middle of the night is especially dangerous. Most studies of driving while sleepy have been on driving simulators, which are not the same as real driving. In the October edition of the Journal Sleep, a study was done to assess sleepiness on real driving. Researchers measured subjective sleepiness, the position of the car relative to the driving lane, objective measure of sleep by measuring brain waves, the duration of eye blinks, line crossing, and speed of vehicle. There were 18 normal sleepers in good health. Study subjects were monitored while driving during the day and night.
Results showed that subjective sleepiness, eye blink duration, and brainwave-measured sleepiness were higher during nighttime driving compared to daytime driving. Also, drivers were more likely to veer toward the middle of the road at night, and this is a new finding. The authors thought it could be due to desire not to go off the shoulder from sleepiness and from reduced visibility of the shoulder. Another new finding was that speed was slower at night and the authors thought this could be due to sleepiness and/or a need to be safer because of decreased visibility.
This study gives us more evidence of the dangers of nighttime driving. And the subjects in this study were healthy and not sleep-deprived. Imagine how much more dangerous these drivers would be if they had a sleep disorder and/or were sleep-deprived. Try to limit nighttime driving if possible. If you do drive at night, be safe and smart about it.