What Is the Definition of Deep Sleep?

During deep sleep, your body undergoes several critical processes necessary for the brain to operate well. When you are deep asleep, you will discover that awakening is complex and that even when you do, you will feel confused and foggy. According to some studies, your mental function may be affected for many minutes or even hours after you arise from the deeper phases of sleep, and you will have a strong urge to return to sleep. This is referred to as sleep inertia.

While in a deep sleep, your declarative memory improves, which refers to your recollections of facts and experiences from your daily life. Your pituitary gland also produces growth hormones that aid in organ, muscle, and tissue healing. If you are recuperating from an injury, this is the time when your body is doing most of its healing. When you fall asleep, your body does not immediately enter a state of profound slumber. Instead, you will pass through several phases of sleep during the night. The two primary stages are non-REM and REM.

The first stage of sleep is non-REM sleep, which consists of three phases. Following that comes REM sleep.

Sleep in the non-REM state

The non-REM stage of sleep is divided into three stages: The first stage occurs when you fall asleep. It usually lasts just a few minutes, and you may quickly reawaken during this time. You may feel rolling eye movements or abrupt muscular spasms during this period.

The second stage comes just before your body enters profound sleep. Your body temperature drops, your heart rate slows, and your breathing becomes shallow. Additionally, the rolling eye motions that occurred during the initial stage will cease.

The third stage is deep sleep, during which your heart rate and breathing rate decrease even more, and your brain and body begin self-repair.

REM sleep

When your body begins to cycle out of deep sleep, you enter REM sleep. Your pulse rate and respiration rate increase, which is when you are most likely to dream.

Around 80 minutes after you go to bed, the first cycle of REM sleep begins. Both REM and non-REM periods of sleep cause changes in your brain and body. Your body will continue to cycle through these phases throughout the night until you awaken. Each cycle, you’ll spend less time in the deepest phases of sleep. This cycle is most likely to repeat four to five times each night. The most straightforward strategy to guarantee that your body receives enough time for deep sleep is to ensure that you have adequate sleep overall. According to the Centers for Disease Control and Prevention (CDC), adults should try to get at least seven hours of sleep every day.