What Exactly Happens When You Fall Asleep

What Exactly Happens When You Fall Asleep

There's a lot we do not know about sleep yet. Why do we fall asleep cycles, why we dream, and why we even need sleep in the first place are questions scientists are still pondering and researching the answers to. But one thing is for certain- after we sleep, and sleep well, we feel better physically and mentally and perform better during the day. 

What happens when you fall asleep?

When you fall asleep, your body undergoes a series of changes that enable the processes that are vital for your overall health. Sleep allows the brain and body to bog down and process recovery, promoting better physical and mental performance the subsequent day and over the long-term.

What happens after you don’t sleep? These fundamental processes are prevented, which can affect your thought process, concentration, energy and mood. As a result, getting the sleep you wish and need- seven to nine hours for adults and even more for youngsters and teenagers- is crucial.

Sleep cycles

During a standard sleep period, you progress through four to five sleep cycles. Each sleep cycle is formed of four individual sleep stages. The four stages of sleep are further condensed into two categories- rapid eye movement (REM) and non-REM sleep. These categories are important because what happens during rapid eye movement sleep is dramatically different from what happens during non-REM stages.

Non-REM stages

The first three stages of sleep are non-REM activities. Stage one is brief, representing the act of dozing off and transitioning into sleep. In stage two the body and mind weigh down as you get into sleep. It’s easiest to be woken up during these first two stages.

In stage three, also referred to as deep sleep, the body is in recovery mode, slowing down even further. At the same time, overall brain activity slows and shows a tell-tale pattern of pulses of activities that are believed to assist prevent unwanted awakenings.

REM stage

The fourth stage is REM sleep. During REM periods, brain activity shoots signals to duplicate levels kind of like when you’re awake- which explains why REM is related to the most intense and realistic dreams. While breathing and pulse increase during REM, most muscles are paralyzed, which keeps us from acting out those vivid dreams.

Each sleep cycle takes between 70 and 120 minutes. Within the first sleep cycles of the night, longer is spent in non-REM sleep. The bulk of REM sleep happens during the second half of the night. The progression of sleep stages and cycles in one sleep period is thought of as sleep architecture.

Your brain when you fall asleep

Virtually every part of the body experiences notable changes during sleep. Upon falling asleep, thousands of neurons within the brain switch from waking to a sleeping state, sending signals throughout the body. While our understanding of the biological role of sleep is still limited, we know it regulates the cardiovascular and immune systems and in turn, metabolism. What happens during sleep is often seen in notable changes in core bodily processes.


Breathing slows during non-REM sleep, respiration reaching its lowest rates during deep sleep stage three. Breathing ramps up and will become irregular during rapid eye movement sleep.

Heart Rate

As with breathing, the vital sign begins to slow during stage one and reaches its slowest pace during stage three. On the opposite hand, during REM sleep, the heartbeat quickens to almost the same rate as when awake.

Muscle Tone

Muscles gradually relax during each stage of non-REM sleep, and therefore the body’s total energy consumption drops. During the REM stage, most muscles are paralyzed in a very condition referred to as atonia. This keeps the legs and arms from flailing in response to your dream’s content. Respiratory and eye muscles stay active, though, and also the darting of the eyes behind closed eyelids is the inspiration for the name rapid eye movement sleep.

Brain Activity

When measured during sleep, brain waves show clear patterns related to each sleep stage. Within the early parts of non-REM sleep, brain waves slow down considerably. However, in stage 2 and stage 3, there are numerous quick bursts of brain activity.

In rapid eye movement, brain activity accelerates, showing markedly different kinds of brain waves. Heightened brain activity is why REM sleep is thought of as the stage most related to vivid dreaming. REM sleep is assumed to enable critical cognitive abilities, including memory consolidation, but non-REM sleep, even with reduced brain activity, is additionally believed to play a job in facilitating proper brain function while awake.


It is during the REM stage of sleep that dreams are more common and intense, but they can occur any time when you're asleep. That said, dreams that happen during non-REM and rapid eye movement sleep tend to indicate different patterns, with REM dreams often being more fanciful, immersive, or bizarre.

Hormone Levels

Sleep and also the body’s internal clock, or biological time, play a crucial role in regulating the assembly of diverse hormones including:

  • Melatonin, which helps you to fall asleep easily
  • Growth hormone, which supports bone and muscle development furthermore as metabolism
  • Cortisol, which is an element of the body’s stress response system
  • Leptin and ghrelin, which regulate appetite

Hormone levels fluctuate during different sleep stages, and quality of sleep may additionally affect daytime hormone production.

What happens if you don’t get enough sleep?

Without enough sleep, your body has a hard time functioning properly. Sleep deficiency is linked to chronic health problems affecting the digestive system, kidneys, blood, brain, and psychological state. Sleep deprived adults and youngsters have an increased risk of injury. Driver drowsiness, as an example, can contribute to serious car accidents and even death. In older adults, poor sleep can lead to falls and broken bones.

Specific consequences of sleep deprivation can include:

  • mood changes
  • anxiety
  • depression
  • poor memory
  • poor focus and concentration
  • poor motor function
  • fatigue
  • weakened immune system
  • weight gain
  • High blood pressure 
  • insulin resistance
  • chronic illnesses like diabetes and heart disease
  • increased risk of early death, etc.

Make your bedroom environment sleep-friendly

Your bedroom should be your sleep sanctuary. You should not use it for anything other than sleeping and sex. When you condition yourself to do that, you will slowly get into a routine and hence stay away from sleep deprivation. Get yourself into a bedtime routine to get a good night’s sleep, every night. 

To make your bedroom sleep-friendly, you just need to visit Livpure’s website to buy extra luxurious, hotel-like bedding without creating a hole in your pockets. Right from plush memory foam mattresses to cloud-like pillows, blankets to cozy into, and Egyptian cotton bed sheets to curl on to- you will get everything you need for your bedroom right there! Do not restrict yourself from getting good sleep anymore! 

The bottom line

Sleep keeps us healthy and functioning well. It lets your body and brain repair, restore, and re-energize. If you don’t get enough sleep, you would possibly experience side effects like poor memory and focus, weakened immunity, and mood changes. If you are having trouble sleeping, ask your doctor or a sleep specialist. They will determine the underlying cause and help improve the standard of your sleep. You deserve good health, so don’t wait anymore to get some decent sleep! 

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