To quote prominent sleep physician, Dr. William Dement: “Drowsiness is the last step before falling asleep, not the first”. Drowsiness means you are seconds away from falling asleep.
Dr. Dement goes on to explain that “The crucial event that occurs as we fall asleep is an abrupt shut down of the neural processes that allow us to perceive the world around us. At one moment we are awake, and can see and hear. A fraction of a second later we are asleep, and we are completely blind and completely deaf.”
Many sleep experts think of sleep as the “default program”, the state that exists when we are no longer working to maintain wakefulness. When we can no longer resist sleep, when our alerting centers can no longer prevent sleep, we transition to sleep.
In my own experience as medical director of Albany Regional Sleep Disorders Center I frequently am asked to evaluate people who have had their driver’s licenses suspended after a drowsy driving related car accident. It is without exception that the person was aware of being sleepy but not one can recall exactly what happened, they had fallen asleep for a brief moment. These are the people who survive, the people who had the “wake up call” so to speak.
Perhaps you’ve witnessed a child or adult fall asleep. For a period of time they are “drifting off” to sleep, they appear and behave “drowsy” and then they suddenly “fall” asleep, we sometimes say they went “out, like a light”.
No one is aware of the exact moment of their own sleep onset, it occurs in a split second. Somewhere between being awake and being a sleep is this so called “drowsy” state.
Now, imagine what this could mean if you’re behind the wheel of a car. At one moment you’re aware of feeling drowsy and in a split second you can be asleep, completely unaware of this incredibly dangerous situation.
The state of drowsiness itself is a significant impairment while driving and has been shown in several studies to be as dangerous as driving drunk. In driving performance testing, 17hours of sustained wakefulness was equivalent to driving with a blood alcohol content of 0.05%.
The National Highway Traffic Safety Administration estimates that each year drowsy driving results in 1,550 deaths and 71,000 injuries with 55% of these crashes involving drivers 25yo and younger. In fact, the most at risk group are young men ages 19y to 26y.
Drowsiness causes: slow reaction times, impaired judgment and vision, decline in attention, decreased alertness, increased moodiness and aggressive behavior, problems with processing information and short term memory.
According to the National Sleep Foundation, signs of drowsiness while driving may include:
Turning up the radio or rolling down the window
Impaired reaction time and judgment
Decreased performance, vigilance and motivation
Trouble focusing, keeping your eyes open or your head up
Daydreaming and wandering thoughts
Yawning or rubbing your eyes repeatedly
Drifting from your lane, tailgating and missing signs or exits
Feeling restless, irritable or aggressive
The best remedy for avoiding drowsy driving is getting enough sleep, that means 7-9 hours of good quality sleep for most adults, however, most people do not get enough sleep. According to the 2002 Sleep in America poll conducted by the National Sleep Foundation, nearly 40% of adults sleep less than 7 hours a night.
Our personal demands and lifestyle choices are in large part responsible for this trend. But our biggest problem is really our own ignorance about the importance of sleep and the impact that it has on every aspect of our lives.
Simply put, we don’t value sleep, we don’t appreciate or respect our need for sleep. It is what we do when the effects of our caffeine filled day cannot keep us awake any longer. It is a time when we can’t text, twitter, talk on the phone or be entertained.
How much sleep is enough sleep will vary from person to person and changes as we age but an individuals sleep requirement stays consistent throughout their adult life.
Most of us need 7-9 hours of sleep at night to feel rested throughout the day. If every night you deprive yourself of an hour of sleep you create a sleep debt and this lost sleep accumulates progressively over time. This is what leads to sleep deprivation and drowsiness. The larger the sleep debt, the greater the tendency to feel drowsy and fall asleep.
In order to avoid the pressure for sleep we call drowsiness, your sleep debt must be zero! So try every day to give your body the sleep it needs especially if driving for extended lengths of time and distance. Avoid driving alone on long trips and take turns driving. Stop driving if you feel drowsy, pull off the road and take a nap, this is one circumstance when caffeine is recommended to help you stay awake.
Contrary to popular belief, caffeine is not a substitute for sleep but can improve alertness especially when combined with a nap.
In addition to making you a safer driver, avoiding sleep deprivation will make you better able to learn and sleep has been shown to be essential in the process of developing memory.
Why do we need sleep? Wouldn’t it be nice if we didn’t? Imagine a truly 24 hour day, a day 1/3 longer! Oh the people you could “friend” if only you had 8 more hours in the day!
No one actually knows for sure why we sleep, it is one of Sciences great frontiers. Sleep affects every part of our life including health, safety, mood, learning, appearance, relationships and productivity.
All animals sleep and we know a lot about what happens when you deprive human beings or other animals of sleep, but why this is essential for life is actually not well understood.
Sleep is critical to our ability to stay awake and alert. Sleeping 7-9 hours a night can help us keep our sleep debt low and improve on our health and safety. Driving when drowsy is extremely dangerous as it impairs our judgment and puts the driver and those around us at risk for injury and even death.
Make sleep a priority tonight and every night!
For more information and a link to a video news report on drowsy driving, visit our Sleep Center Page.