There’s almost nothing better than waking up feeling rested and refreshed after a good night of sleep. It’s hard to imagine why anyone would want to skimp on sleep. After all, research has shown that getting a full night’s rest can make you feel more focused and productive, while lack of sleep can leave you feeling sluggish and anxious. What’s more, the brain is incredibly active during sleep, with many different kinds of changes taking place throughout the night. And it’s not just the brain that benefits from a good night’s sleep; the entire body takes advantage of restful sleep, including helping you digest food, eliminate waste, regulate your heart rate, and more.
The study of sleep is a very young science. Its history goes back only about a century, but the importance of getting adequate sleep is widely recognized and supported by both the medical community and public health authorities. Insufficient or inadequate sleep can negatively impact your quality of life and lead to many serious diseases and conditions, including heart disease, stroke, high blood pressure, diabetes, and obesity. Getting enough sleep can even help you manage stress and depression, improve your memory, and protect your mental health in the long run.
Insufficient or poor-quality sleep can also interfere with how your immune system works, making you more susceptible to infections. And if you’re not sleeping well, you may be more likely to develop chronic inflammation, which can contribute to conditions such as arthritis and cardiovascular disease.
During the first phase of sleep, known as stage 1 non-REM (non-rapid eye movement) sleep, your heart rate and breathing slow down, muscles relax, and you enter a period of relatively light slumber. This preliminary stage is marked by the appearance of EEG tracings with low voltage and considerable representation of ta-wave activity (4-7 Hz). Some experts have also begun to include in this category the very brief bursts of 11-15 Hz activity called sleep spindles, which are associated with a certain degree of wakefulness.
The next stage of sleep is REM (rapid eye movement) sleep, which is distinguished by the rapid, repetitive movements of the eyes that mimic those of awake people. This is a highly activated state, characterized by diffuse bodily activation, and it produces EEG tracings with lower amplitude and more frequency than those of NREM sleep stages 2 and 3. The occurrence of this activation has led to the view that REM is not part of the normal restful sleep cycle.
During this stage, you also experience dreaming. Whether you remember the details of your dreams or not, this part of sleep is important because it’s thought to play an important role in the formation of memories and emotions. In addition, it’s believed that REM sleep plays a critical role in maintaining and promoting mental health and emotional stability, and in supporting normal growth and development during childhood, adolescence, and adulthood. It is also believed to help boost muscle mass and strength and supports healthy pregnancy and childbirth in women.