The brain is quite important in the human body as it controls all the functions of the human body whether voluntary or not. The brain is divided into three main parts, the forebrain which controls the ability to feel, learn and remember, the brainstem which consists of the mid-brain and part of the hind- brain and the hind-brain which controls involuntary functions. Disorders which may attack the brain include Alzheimer's disease, epilepsy, Parkinson's disease and meningitis.