The Importance of Sleep
Sleep is an essential component of healthy living. Without it, you can suffer from a range of health problems that affect both your physical and mental well-being.
Insufficient or inconsistent sleep can lead to heart disease, high blood pressure, diabetes, obesity and depression. It can also impact your ability to concentrate and make good decisions. Sleep deprivation is linked to poor work performance and increased risk of accidents at home or on the road, and can have a significant negative effect on your memory.
Throughout the night, you cycle through several phases of sleep, starting with non-REM (NREM) or deep sleep and moving to REM or dreaming sleep as the night progresses. Each stage of sleep is associated with a different set of brain waves and changes in body functions, such as heart rate, breathing and body temperature. On average, you spend about two thirds of the night in NREM sleep and one third in REM sleep. On a normal night, you will cycle through about four or five cycles of this sleep pattern.
Sleep provides the body and mind with a time to rest, repair and regenerate. It strengthens the cardiovascular and immune systems, rebalances hormones, helps regulate metabolism and promotes a sense of wellbeing. In addition to this, the brain processes and organizes the information you take in during the day and converts short-term memories into long-term ones. Without adequate sleep, this process is impaired and can result in a loss of memory.
The need for sleep is universal in all animal species and is necessary for survival. The reason for this is not fully understood but could be due to an evolutionary advantage of being less active at night when there was a greater chance of being attacked by predators. Another theory is that sleep protects the brain from damage. Research has shown that the brain is able to restore cells that have been damaged or used during the day.
For the past half-century or so, scientists have been trying to understand the nature of sleep and its importance. Early studies focused on identifying the slow brain wave activity that characterizes NREM sleep. These were discovered to be primarily generated by local cortical networks, rather than by the thalamus. This led to the hypothesis that slow sleep waves are a fundamental default mode of cortical activity, regulated at the local level and not the global level (Krueger and Obal, 1993). A more recent study supported this hypothesis and showed that the thalamic gating mechanism that blocks sensory inputs during sleep is modulated locally, to preserve the homeostasis of the relevant local cortical networks (Cirelli and Tononi, 2014).
Insufficient or inconsistent sleep can negatively affect your quality of life in many ways. It can cause you to feel irritable, moody and lethargic, and can make it difficult to concentrate and remember things. It can even lead to weight gain and poor eating habits, as you are more likely to overeat when tired. In fact, researchers estimate that insufficient or inconsistent sleep causes more than 50-70 million Americans to experience symptoms of sleep deprivation each year. The good news is that by prioritizing a regular sleep schedule and getting a good night’s rest, you can improve your physical and mental health.