Our brain is one of the most complex and perplexing organs of the human body. It controls all of our thoughts, actions, memories, and emotions without taking a single break. All these are done by our brain when we are awake. But do you think that this is the same case while we are asleep? Read out this blog to know about the science of sleep.



Sleep is considered a time for rest, a break from all our stress. Sleep helps us cleanse our minds, support learning, and memory. Sleep is divided into two categories based on brain activity.

Non-Rapid Eye Movement (Non-REM) Sleep

Non-REM sleep has 3 stages that usually last between 5-15 minutes. All of these stages happen before the REM sleep.

I stage Our eyes remain closed, but it is easy for us to wake up. This stage usually lasts for about 10 minutes but can vary with individuals.

II stage The preparatory phase where the body makes itself ready for deep sleep. It lasts for around 10-25 minutes.

III stage – This is the stage in which you one is in deep slumber. It is difficult to wake someone who is in this stage.

Rapid Eye Movement (REM) Sleep

REM sleep happens about 90 minutes after we fall asleep. Dreams arise for us in this type of sleep.


Unlike us (us refers to our conscious part), our brain doesn’t go offline while we are asleep. The brain pulls out a highly coordinated string of events in order to maintain the sleep stages properly. The HYPOTHALAMUS is responsible for cutting off some biosignals and transcending to sleep. Neurons in these areas are called the ventrolateral preoptic nucleus (VLPO). These control the arousal-promoting centres. By shutting these centres, the VLPO promotes sleep.


Circadian rhythm forms the body’s internal clock . It is a 24-hour cycle. The sleep-wake cycle is one of the most important circadian rhythms in the body. The circadian rhythms are synchronized by the master clock in the brain, it is influenced by the environmental factors especially light.

The master clock is referred to as the ‘Circadian pacemaker’. It is found in the Suprachiasmatic nucleus (found in the hypothalamus).

During the day, the master clock sends signals that generate alertness to keep us awake. At night it induces the production of melatonin (a hormone that promotes sleep) which helps us sleep at night.


Melatonin is a hormone produced by the pineal gland in the brain at night. Our body’s circadian rhythm is influenced by the level of melatonin produced, hence melatonin can be considered the regulator of the sleep-wake cycle. During the day, the amount of melatonin produced is less, and high during the night.


Dreams are our subconscious thoughts. It is a universal experience that involves thoughts, images and sensations. Researchers believe that dreaming helps in improving memory processing where the brain concise the information received while we are conscious. Dreams often occur during REM sleep.


It would be amazing if we could control our dreams right!? Wait, what! Is this actually possible?

Actually, the answer is YES!! The type of dream where the person is aware that they are dreaming and can control the upcoming events is called lucid dreaming. This type of dreaming feels vivid and real. It is like a person kept in a Virtual Reality chamber or placed in a video game. 

So how do we know if we are lucid dreaming:

  • Awareness that we are actually sleeping.
  • Dreams tend to be vivid
  • We exert control over our dream
  • We can actually feel the stuff happening in the dream.
  • It can be a bit intense.

 The following are the most common triggers for lucid dreams:

  • Desires
  • Memories
  • Fears
  • Healing

Studies show that there is an increase in activity in the dorsolateral prefrontal cortex, bilateral frontopolar, prefrontal cortex, the precuneus, the inferior parietal lobules, and the supramarginal gyrus of the brain which are associated with higher cognitive functions.


  • Lucid dreamers are said to be more creative than their peers
  • Helps overcome nightmares
  • Relieve anxiety


  • It may lead to sleep problems.
  • Our brain may not get proper rest since it keeps stimulating conditions of your desire.
  • Sleep deprivation due to lucid dreaming may also lead to depression.
  • It might lead to confusion and can lessen the ability of a person to differentiate the real world from that of their dream.

Bonne lecture et bonne nuit 🙂

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