Sleep is not just a “resting brain.” It is a basic necessity of life and is as essential to our health as air, food, and water. When we sleep well, we feel refreshed, alert, and ready to face the challenges of life. If we don’t get enough sleep, our jobs, relationships, health, and safety can suffer (National Sleep Foundation, 2018).
- Occupying approximately 30% of each day, sleep is a complex, highly organized, physiological state and it is crucial to the proper functioning, restoration, and repair of our bodies.
- Sleep is a term derived from the Latin word “somnus,” meaning a natural, periodically recurring physiological state of rest for the body and mind. Sleep is defined as a behavioral state characterized by little physical activity and virtually no awareness of the outside world.
- Meiner (2014) defines sleep as a state of inactivity that is required to remain active.
Sleep and wakefulness are regulated by the hypothalamus, which contains both a sleep center and a wakefulness center. Both are also influenced by the thalamus, limbic system, and reticular activating system (Meiner, 2014). While the quantity and quality of sleep vary from person to person, the amount of sleep we need to stay healthy is related to the amount of sleep we need to not feel sleepy the next day (National Sleep Foundation, 2018).
Yet, the processes and function of sleep are not completely understood. In the aging population, these processes and functions are even less understood since “normal” sleep can be defined in a variety of ways and the definitions are often inconsistent.
Our sleep needs remain constant throughout our lives, although we may meet those needs in a variety of ways. It is a common misconception that sleep needs decline with age. Whether a person is 2 years old or 82 years of age, most people still require 7 to 9 hours of sleep each night in order to remain healthy. When we sleep well, we awake refreshed and alert (National Sleep Foundation, 2018; Neikrug & Ancoli-Israel, 2010). When we don't sleep well, every aspect of our lives can be affected.
In the same way that our bodies change gradually over time, so, too, does our experience of sleep change as we age. Physical, medical, and psychological changes associated with aging, lifestyles and behaviors, stress, poor sleep habits developed over the years, and medications can all affect the quality and quantity of our sleep (National Sleep Foundation, 2018).
As United States society has changed, we work more and sleep less. Businesses and entire industries are open 24 hours a day, every day of the year. Our bodies' need for sleep, however, has not changed. The result is that millions of Americans suffer from a "sleep debt."