Sleep is a state of reduced mental and physical activity in which consciousness is altered and certain sensory activity is inhibited. During sleep, there is a marked decrease in muscle activity …

Sleep is a body process that allows your body to rest, repair and restore itself. You need sleep to function properly. Lack of sleep has links to many health issues.

Jul 10, 2025 · Everyone needs sleep, but about one in three American adults don’t get enough of it. The consequences of sleep deprivation are serious, so it’s worth learning why sleep …

May 15, 2024 · About Sleep Key points Good sleep is essential for our health and emotional well-being. Getting enough sleep and good sleep quality are essential for healthy sleep. The …

Feb 25, 2025 · Sleep is a complex and dynamic process that affects how you function in ways scientists are now beginning to understand. This webpage describes how your need for sleep …

Nov 5, 2025 · Sleep usually requires the presence of relaxed skeletal muscles and the absence of the overt goal-directed behaviour of which the waking organism is capable. The characteristic …

1 day ago · Sleep is critical to your health and well-being. Learn about why you need sleep, how much you need, and how you can get better sleep.

What exactly does sleep do for your body and mind? Here’s what researchers know about the science of sleep—including the stages of sleep, your biological clock, health connections and …

Jul 27, 2025 · Sleep is composed of two major types: non-REM (NREM) sleep and REM (rapid eye movement) sleep. Each plays a unique role, and both are critical for mental and physical …

Sleep is largely driven by the body’s internal clock, which takes cues from external elements such as sunlight and temperature. The body’s natural sleep-and-wake cycle is reasonably attuned to...