What Happens When You Sleep?
Source: Hartford Insurance email list
Sleep is a mysterious and complex part of our lives, and not at all the passive state it appears to be. Some functions of the body and brain are actually more active during sleep than they are during waking hours, busily performing a collection of housekeeping tasks necessary for health and homeostasis.
During sleep, your brain consolidates the information you have taken in during the day, cementing new memories in long-term storage. It also clears away toxins that have built up in your brain during your waking hours that could otherwise lead to neurodegenerative diseases, such as Alzheimer’s.
The rest of your body also undergoes its own nightly tune-up as you sleep. The immune system is strengthened, tissue and nerve cells are renewed and repaired, and hormones are synthesized. When you get the right amount of rest, you awaken with your body restored and ready to take on the demands of a new day.
The Sleep Research Society says that sleep influences nearly all of the body’s molecular, cellular, physiological and neurobehavioral processes. Meeting our bodies’ need for sleep is essential to life, health and productivity.
Source: https://www.sleepadvisor.org/why-do-we-sleep/
Every night when you lie down to sleep, your body and brain undergo a variety of changes that are cued by your circadian rhythm, or your internal biological clock. In response to external and internal factors, your circadian rhythm dictates the release of hormones that encourage your brain to transition from wakefulness to a sleep state.
When you begin to fall asleep, your body temperature begins to drop as your brain waves slow. Your brain then cycles through the four stages of sleep which consists of two types of sleep: non-rapid eye movement (non-REM) sleep and rapid eye movement sleep (REM) sleep.
The third stage of non-REM sleep is referred to as deep sleep. This sleep stage is central to our ability to recover from exercise and injury. This is followed by a single stage of REM sleep.
REM sleep is different, with brain waves similar to those that occur when we’re awake. Experts believe both non-REM and REM sleep are important for memory consolidation.
Each of these non-REM/REM cycles lasts about 90-110 minutes, and we continue to cycle through each stage while we sleep. To reap the full benefits of a night’s rest, healthy adults should experience a sleep duration of around 7-9 hours each night.