Alzheimer's disease is a progressive condition that damages areas of the brain involved in memory, intelligence, judgment, language, and behavior. (See an
illustration of these areas of the brain.) It is the most common form of mental decline, or dementia, in older adults.
Autism is not a disease, but a developmental disorder of brain function. People with classical autism show three types of symptoms: impaired social interaction, problems with verbal and nonverbal communication and imagination, and unusual or severely limi
Guillain-Barre (ghee-yan bah-ray) syndrome is a disorder in which the body's immune system attacks part of the nervous system. The first symptoms of this disorder include varying degrees of weakness or tingling sensations in the legs. In many instances th