Inability to Concentrate
If you've ever dragged yourself into the office on Monday after a restless weekend and had to feign interest in a long meeting, you may be familiar with another sign of sleep deprivation -- an inability to concentrate.
Sleep-deprived subjects in studies are not only more likely to perform poorly on tests requiring concentration, but also, they're more likely to overestimate their performance. They underestimate the effects of sleep deprivation on their ability to concentrate [source: Downs].
Those effects increase as our sleep debt builds. A person getting five hours of nightly sleep for a week will perform better on tasks requiring concentration than a person who gets four hours a night for a week.
Caffeine offers a quick fix and improves concentration (for a little while, at least), with effects peaking within about an hour of consumption [source: Lieberman].
If you've noticed a change on the scale, you may have recently had a change in your sleep habits. Keep reading to learn about the connection between sleep and appetite.