Behind stress and colds, CU students cited sleep as one of the main factors influencing academic performance in a 2002-2003 survey. Some experts estimate that about half of the adult population is sleep deprived, and college students are especially at risk of not getting enough sleep. But what exactly is sleep, and why do we need it?

Sleep is a part of your body's internal clock (called a circadian rhythm), which regulates wakefulness, body temperature, and hormones. Sleep is a period of decreased consciousness, and is broken up into various stages. These are categorized as either rapid eye movement (REM) or non-REM. During non-REM sleep, body temperature drops and heart rate decreases as your body prepares for deep sleep. This occurs in the beginning of the sleep cycle. Your muscles may show spontaneous periods of tension and relaxation during this phase. REM sleep occurs toward the end of the sleep cycle, and is when you are most likely to have dreams. Your eyes literally move rapidly back and forth during this phase. It's thought to be the time when your brain commits items to long-term memory and attends to other mental processes, as well.

Sleep is a necessary component of our lives for various reasons. During sleep, memories are consolidated, hormones related to growth and the immune system are released, and the body can devote energy to muscle and tissue repair. Clearly, sleep is not a waste of time. Getting enough sleep will positively contribute to your health and academic success.

For more information about sleep, use the following links:

National Institutes of Health

National Sleep Foundation