The Science of Sleep

Lexile: 950 | Grade: 6

Passage

Have you ever wondered why your body needs sleep? Even though it seems like you're doing nothing, your brain and body are busy during those hours of rest. Scientists have discovered that sleep is essential for memory, learning, physical health, and emotional balance. It’s not just a break—it's an active process that helps you function at your best.

Sleep happens in cycles, each lasting about 90 minutes. These cycles include different stages, such as light sleep, deep sleep, and REM sleep. REM stands for Rapid Eye Movement, and it’s the stage where dreaming usually occurs. During REM sleep, your brain becomes active, almost as if you're awake, even though your body remains still. This stage is especially important for processing emotions and storing memories.

Deep sleep, on the other hand, is when the body focuses on repair. Muscles grow, tissues heal, and energy is restored. Without enough deep sleep, people may feel tired no matter how long they stayed in bed. That’s because not all sleep is equal—quality matters as much as quantity.

Lack of sleep affects more than just your mood. Studies show that not getting enough rest can make it harder to focus, solve problems, or control emotions. Over time, sleep deprivation can even lead to health problems like heart disease, obesity, and diabetes. Children and teenagers are especially affected because their brains and bodies are still developing.

But getting good sleep isn’t just about how long you stay in bed. It’s also about your sleep habits, or what experts call 'sleep hygiene.' Things like turning off screens an hour before bedtime, keeping a regular sleep schedule, and creating a quiet, dark room can help your body know when it’s time to rest.

In a world full of distractions, sleep often gets pushed aside. But science is clear: sleep is not a luxury—it’s a necessity. Understanding how sleep works can help you make better choices and feel your best every day.