Dreams are hallucinations that occur during certain stages of sleep. When we are immersing in deep sleep, we are no longer able to feel our bodies, and the whole night passes like a blink of an eye. However, have you ever wondered what happens to the body as your consciousness immerses itself in the world of dreams?
Scientists still do not agree what is the purpose of the dreams. The most common theories claim that dreams are helping the memory to memorize newly learned things, as well as it is said that dreams are a source of creative inspiration, or even a way for the brain to prepare the body for possible future challenges. While the debate over the nature and necessity of dreams does not hold, the physiological consequences of dreams are clear.
It all starts with a brain strain that puts you into sleep mode and shuts down the muscles when you go into the rapid eye movement stage (REM). All the body except your eyes is temporarily paralyzed. Such a function is extremely important to avoid the factor of translating dreams into reality. If the body were not temporarily paralyzed during sleep, the sleeping person would physically mimic the movements experienced in the dream and that might cause injuries.
The frontal cortex part where the mind lies is also shut down during sleep. Without logic, reasoning, and environmental assessment, the usual rules of space and time are no longer applied. When the signs of the real world disappear, you can see and do unrealistic things in dreams, such as flying. When certain parts of the body turn off, other parts turn on. Although your eyes have nothing to look at, the visual cortex of your brain – the area that interprets images – comes to life. Therefore, you see the whole action in your mind. Sleep is a period during which the brain engages in many of the activities necessary for life, closely related to quality of life.
According to experts, there are two main processes that regulate sleep: circadian rhythms and the driving force of sleep. Circadian rhythms are controlled by a biological clock in your brain. One of the main functions of this clock is to respond to light signals by increasing the production of the hormone melatonin at night and, when light is felt, to stop the production of melatonin. Completely blind people often have sleeping problems because they cannot detect and respond to light.
The driving force of sleep also plays an important role. Your body craves for sleep just like it craves for food. During the day, the tiredness is increasing, and when it reaches a certain limit, you need to sleep. The essential difference between tiredness and hunger is that your body cannot force you to eat when you are hungry, but when you are tired, it can make you fall asleep, even if you are in a meeting or driving. When you are exhausted, your body can even get involved in one or two second microsleep episodes when your eyes are open.
Although people spend one to two hours a night during the REM sleep phase, most of them do not remember their dreams. Scientists do not know exactly why, but it can be a coping-type mechanism: if you remember everything, it would be too difficult for your mind to distinguish between real things and dreams.