The Science Behind Sleep

Sleep is incredibly important in order to function as a normal human being. We all know that the average adult requires around seven hours of sleep, if not more, and adolescents need more time than that in order to rejuvenate their growing bodies and brains. Sleep allows us to recharge our energy, and without it, we wouldn’t be able to get the rest we need to keep going. But what is the science behind sleep?

For starters, sleep is regulated by the circadian rhythm, which is our internal 24 hour clock. When we’re sleeping, there are two phases that we as humans go through: NREM, which is non rapid eye movement sleep, and REM, which is rapid eye movement sleep. The first phase has three stages within it, and the second phase only has one stage, which adds up to a total of four stages of sleep: Stage 1 NREM, Stage 2 NREM, Stage 3 NREM and REM. These different phases are all responsible for different things while we’re unconscious, and they repeat like a cycle until we wake up.

During Stage 1 NREM, we undergo a light level of sleep, where we’re just transitioning from being awake to being asleep. Heart rate slows down and your breaths become heavier and slower, and this stage lasts a few minutes. Next, during Stage 2 NREM, your body continues to head into a deeper sleep, your vitals continuing to slow down as your brain waves decrease in frequency too. Stage 2 is the longest stage of sleep in the cycle. Stage 3 NREM is when the slowed vitals reach it’s final point, as everything in your body has relaxed and slowed down. Finally, during the final stage, which is REM sleep, parts of your body, such as blood pressure, heart rate and breathing, begin to increase. This stage is also the stage in which dreams are most likely to occur, and, as the name suggests, your eyes will be making rapid movements under your eyelids.

Sleep, although very complicated, is important to humans because it ensures that we are functioning well, and it is a necessity, no matter how trivial it may seem.