What Happens During Sleep?

Most people are well aware that sleep is essential to their health and well-being. A good night’s sleep leaves them feeling refreshed and ready to face the day. Sleep is also important for a person’s brain function, maintaining their physical health, and supporting their growth and development. Over time, not getting enough quality sleep can raise the risk for chronic (long-term) health problems such as heart disease, high blood pressure, diabetes, depression, and obesity.

While we all know that sleep is important, not many people have a clear understanding of what exactly happens during slumber. In fact, even a slight misperception about how sleep works can lead to poor habits that can have lasting negative effects on a person’s health. It is also a common misconception that sleep only occurs during the night, when in reality it is an active process that takes place throughout the entire 24 hours of every day.

There is no universal answer as to how much sleep each person needs, as the amount varies from one individual to another. However, there are some common practices that can help ensure healthy sleep, such as going to bed and waking up at roughly the same times each day and following a nightly routine that includes calm activities, like reading or relaxing exercises. It is also helpful to avoid the use of electronic devices, especially those that emit blue light, close to bedtime, as these can inhibit the release of melatonin.

The first stage of non-REM (NREM) sleep is characterized by the slowing down of heart and breathing rates, the reduction of muscle activity, and the fading away of eye movements. The duration of this phase gradually decreases through the night as you move into deeper stages of NREM sleep.

During the second NREM sleep stage, your eyes will remain closed and all other motor activity will cease. During this time, your heart rate and breathing will continue to slow down, muscle tension will decrease, and the electrical activity in your brain will begin to slow down and eventually become completely quiet (with the exception of brief moments of higher frequency activity).

This is the final NREM sleep stage where your body will prepare itself for awakening. Your heart rate will return to its normal level, and your body temperature will rise slightly. The electrical activity in your brain will reach its lowest levels, and your muscles will become more relaxed.

The importance of good quality sleep is widely recognized in healthcare, but more work must be done to incorporate sleep goals into education, family life, and public health. There is also a need to develop new and easily accessible resources that advise people on what they can do to improve their own sleep.