Though we all have varying needs for sleep (one person's five-hour beauty sleep may leave another person drowsy), you should generally get between seven and nine hours of sleep in a single day. You create a sleep debt when you fall an hour or two short of your needed sleep day after day. Sleep deprivation over the course of a week can lead to cognitive difficulties that are similar to those experienced by stroke patients [source: Stevens]. The result can be dangerous for those working long hours. Studies show medical residents experience more accidents after putting in long shifts [source: Durmer].
Drivers who are sleep deprived are as bad as -- and sometimes worse than -- intoxicated drivers in studies that have tested both groups using driving simulators. According to the National Highway Traffic Safety Administration, there are around 100,000 traffic accidents a year due to sleep deprivation and 1,550 fatalities [source: Breus].
Sleep deprivation affects your body and mind in myriad ways. As a sleep debt builds, your ability to concentrate decreases. Thinking becomes labored, and vision becomes blurry. You may experience headaches or feel especially agitated or moody. You start to forget things.
The immune system takes a hit as well. When sleep deprived, you have fewer white blood cells, and those you do have aren't very effective in destroying unwanted antigens in the body. Your body temperature drops, and your heartbeat can become erratic. The greater the sleep debt, the more difficult it is to process visual information.
You're feeling weak, distracted, foggy and upset. You have a headache, and you can't see straight. Think these are bad circumstances for making decisions? Research shows that when you're sleep deprived, there's more activity in the parts of your brain that analyze positive outcomes and less activity in parts responsible for weighing negative outcomes.
Whether you're caring for patients in a hospital, pulling a double shift at the factory, piloting a passenger plane or driving a truck, you're more likely to make an error [source: Durmer].
In what other ways does sleep deprivation affect decision making? Odds are, you're not ready for a weekend in Vegas.