Sleep differs from wakefulness in terms of the ability to react to stimuli, consciousness is altered and during sleep there is reduced mental and physical (muscle) activity, certain sensory activity is inhibited and interactions with the surrounding environment are decreased, but the brain patterns are still active.
Sleep is an important part of your daily routine—you spend about one-third of your time doing it. Quality sleep and getting enough of it at the right times, is as essential to survival as food and water. Without sleep you can’t form or maintain the pathways in your brain that let you learn and create new memories, and it’s harder to concentrate and respond quickly.
During sleep our body´s systems are in an anabolic state, helping to restore the immune, nervous, skeletaland muscular systems; these are vital processes that maintain mood, memory, and cognitive function, and play a large role in the function of the endocrine and immune systems.
Sleep is important to a number of brain functions, including how nerve cells (neurons) communicate with each other. Recent findings suggest that sleep plays a big role, when it removes toxins in your brain and in the body that build up while you are awake.
Research shows that a chronic lack of sleep, or getting poor quality sleep, increases the risk of disorders including high blood pressure, cardiovascular disease, diabetes, depression, and obesity.
Humans may suffer from various sleep disorders, including: 1) dyssomnias such as insomnia, hypersomnia, narcolepsy and sleep apnea; 2) parasomnias such as sleepwalking and rapid eye movement sleep behavior disorder, bruxism; and 3) circadian rhythm sleep disorders.
Nowadays, with the lightning from the screens of electronic devices such as smartphones and televisions, typically associated with daytime, people have trouble with sleeping as this light disrupts the release of the hormone melatonin, which is needed to regulate the sleep cycle.
Sleep is a complex and dynamic process that affects how you function in ways scientists are now slowly beginning to understand.