The brain has fascinated scientists and philosophers for centuries. Although it comprises only 2% of the body’s total weight, each beat of the heart delivers 20% to 25% of the body’s blood to the brain where nerve cells use, on average, 20% of the body’s oxygen and fuel. There are over 400 billion capillaries in the brain. These blood vessels carry oxygen, glucose, nutrients, and hormones to the brain for its use, and they help rid the brain of waste products (Alzheimer’s Association, 2017).
The brain receives information through the five senses of sight, smell, touch, taste, and hearing. As the main organ of the human body used to interpret the senses, initiate body movement, and control behavior, the brain is the source of all the qualities that define our humanity—it is the crown jewel of the human body (Mayfield Clinic, 2016; NIH, 2017).
Currently, there is an acceleration of research in neurological and behavioral science with a goal of providing new insights into the mysteries of the brain and developing new treatments for mental and physical conditions. At the forefront of research on the brain and other elements of the nervous system is the National Institute of Neurological Disorders and Stroke (NINDS), which conducts and supports scientific studies in the United States and around the world (NIH, 2017).