Electrical activity within the brain changes depending on the current mental state of an individual. For example, the brainwaves of a sleeping person are vastly different than the brainwaves of an individual that is wide awake.

Simply, viewing the brainwave patterns will provide great insight into that individual’s mental state. For example, those suffering from attention deficit disorder (ADD) or attention deficit hyperactivity disorder (ADHD) tend to produce an overabundance of slower Alpha/Theta brainwaves.

From years of research, it is clear that not only are brainwaves related to specific functions of the body and mind, but they can be stimulated to change a person's mental state, and even help treat a variety of physical and mental disorders. By stimulating the brain to produce or decrease certain brainwave bands, it is possible to induce a variety of mental states and emotional reactions.