Recognising Sleeping Behavior
Most people thought sleep was a passive activity in which the body and brain were asleep before the 1950s. According to neurologist Mark Wu, M.D., Ph.D., a sleep expert at Johns Hopkins, “yet it turns out that sleep is a period during which the brain is involved in a variety of critical to life activities—which are directly tied to quality of life.”
Many of the hours that researchers like Wu are awake are spent trying to learn more about these processes and how they impact both physical and mental health.
Here is a glimpse into the significant (and frequently unexpected) findings made by sleep scientists as well as what they are currently striving to learn about the science of sleep.
Not Every Sleep Is the Same
Your brain will alternate between REM (rapid-eye movement) sleep and non-REM sleep during the duration of your sleep.
Non-REM sleep, which consists of four stages, is the first phase of the cycle. The first phase occurs between the awake and sleeping states. The second is light sleep, during which respiration and heart rate are in control and body temperature decreases. Deep sleep occurs in the third and fourth stages. Newer research indicates that non-REM sleep may be more crucial for learning and memory than REM sleep, which was traditionally thought to be the most significant sleep stage for these functions. Non-REM sleep may also be more relaxing and restorative than REM sleep.
The eyelids move quickly beneath closed lids as you cycle into REM sleep, and your brain waves resemble those of alertness. As we dream, our breathing quickens and we experience momentary paralysis of the body.
The cycle then repeats again, but with each iteration you spend more time in REM sleep and less time in the deeper phases three and four of sleep. You’ll go through four or five times on a regular night.
Built-In Sleep Controls in Your Body
According to Wu, circadian rhythms and sleep drive are the two fundamental mechanisms that control sleep.
The biological clock that regulates circadian rhythms is housed in the brain. One important function of this clock is responding to light cues by increasing melatonin production at night and turning it off when it detects light. Total blindness makes it difficult for some people to fall asleep because they are unable to recognise and react to these light cues.
The need for sleep, like the need for food, is a major factor in sleep drive. Your need for sleep increases during the day, and at some point, you must go to bed.
A significant distinction between hunger and sleep
One significant distinction between hunger and sleep is that your body cannot compel you to eat when you are hungry, whereas it may put you to sleep when you are exhausted, even if you are in a meeting or driving. When you’re worn out, your body is even capable of short bursts of microsleep that last just one or two seconds. By reducing your body’s drive to sleep, taking a nap later in the day for longer than 30 minutes can disrupt your night’s sleep.
Why Sleep Is Important
The fact that sleep has a substantial impact on brain function won’t come as a surprise to you if you’ve ever felt hazy after a restless night. First, adequate sleep is essential for “brain plasticity,” or the brain’s capacity to change in response to stimulus. Too little sleep makes it difficult for us to digest what we’ve learnt during the day and makes it more difficult for us to recall it afterwards. Additionally, it’s thought that sleep may facilitate the elimination of waste materials from brain cells, which happens less effectively when the brain is awake.
The remainder of the body also needs sleep. The threats to a person’s health increase when they don’t get enough sleep. Seizures, migraines, high blood pressure, and depressive symptoms all get worse. Immunity is weakened, which raises the risk of disease and infection. The metabolism is influenced by sleep as well; a person who is otherwise healthy can develop prediabetes after just one night of interrupted sleep. Wu asserts that there are very significant correlations between sleep and health.