The Science of Sleep: Understanding What Happens When You Sleep
Sleep helps your body, particularly your brain, to heal itself and perform important functions like the removal of waste and hormone release. Sleep is necessary for optimal health. If you are suffering from any sleep disorder or want to make your sleep better, visit us at the Koala® Center For Sleep & TMJ Disorders. For more information, contact us or book an appointment online. We have convenient locations across the U.S. in Bloomington IL, Peoria/Dunlap IL, Mishawaka IN, Kansas City MO, El Paso TX, and Wausau WI.
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While you sleep, your body undergoes a series of processes. Contrary to popular belief, the brain remains active while you sleep. Sleep is extremely important for “brain plasticity,” which is the brain’s ability to process information. Additionally, while you sleep, your brain removes waste and toxic byproducts that accumulate while you’re awake.
Simultaneously, at the cellular level, the body engages in repair and restoration. The cells undergo repair, addressing any damage or wear incurred during waking hours. If you don’t get enough sleep on a regular basis, you are at a higher risk of various physical and emotional health problems. Sleep plays a role in your immunity, metabolism, hormone levels, stress resilience, and many other health markers.
Overall, there are many important ways in which the quality of our sleep is linked to our health and quality of life. That’s why humans sleep for about a quarter to a third of their lifespan. If you’re having trouble sleeping or don’t feel well-rested after you wake up, you may have a sleep disorder. It’s important to have sleep disorders diagnosed before they significantly affect your wellness.
While scientists used to believe that people’s brains and bodies were inactive while they slept, this is untrue. While we sleep, our brains and bodies do quite a bit of work to keep us healthy. Sleep provides time for the brain and body to decelerate and focus on the processes involved in recovery. Everyone needs sleep to allow their brain to store and process information acquired throughout the day, solidify memories, clear waste, and restore focus and energy levels.
The consequences of inadequate sleep can be very serious. When you don’t sleep enough, fundamental recovery processes are disrupted. This has a significant effect on cognitive functions such as problem-solving, rational thinking, emotional regulation, and concentration. In summary, it’s crucial to get enough sleep, as it is directly correlated with proper daily functioning.
Sleep happens in four unique stages, which are:
– Stage 1 or N1 – This stage marks the initial moments of sleep. N1 is a light sleep stage that lasts about 1 to 7 minutes, during which you can be easily awakened. If you are not disturbed during this stage, you will quickly enter N2.
– Stage 2 or N2 – In N2, you enter a deeper level of sleep where eye movement ceases, and the body prepares for rest by relaxing the muscles and slowing breathing and heart rate. While this stage is still considered a light sleep stage, people usually spend around half their sleep in N2. On the first sleep cycle, this stage lasts 10 to 25 minutes but tends to increase in duration throughout the night.
– Stage 3 or N3 – Is also known as slow-wave sleep, N3 is a crucial stage for restorative sleep. During this deep sleep phase, the body repairs tissues, builds bone and muscle, and strengthens the immune system.
– Rapid eye movement (REM) sleep – REM sleep is characterized by rapid eye movements as well as vivid dreams. This stage is essential for learning, memory and creativity. Normally, you do not enter REM until at least 90 minutes into your sleep.
These stages repeat several times throughout your sleep in a process known as the sleep cycle. Sleep cycles last from 1 to 2 hours and vary based on your age, sleeping patterns, and sleep hygiene.
Your body knows when it’s time to wake up thanks to a special part of the brain called the suprachiasmatic nucleus, or SCN. The SCN, located in the hypothalamus, regulates your sleep-wake cycle. The optic nerve, located in the eyes, sends messages to the SCN. When morning light comes in, the optic nerve communicates this to the SCN. In response, the SCN sets off a series of actions to let your body know it’s time to wake up.
This whole process is part of your body’s internal clock, which is also called the circadian rhythm. When your body is exposed to light in the morning, it releases cortisol, which is called the “awakening hormone.” In short, your body is wired to wake up when the morning light shines through your window.