Disorders of the Nervous System

Psychological disorders : Nervous-system disorders span psychological and specific organic disease. Psychological (mental) disorders are a wide range of conditions affecting mood, thinking or behaviour severely enough to disrupt multiple areas of a person's life and cause real distress; major categories include intellectual disability (ID, formerly called mental retardation), autism spectrum disorder (ASD), bipolar disorder (BD), depression, anxiety disorder, attention deficit hyperactivity disorder (ADHD) and stress-related disorders.

Parkinson's disease and Alzheimer's disease : Parkinson's disease results from progressive degeneration of the dopamine-producing neurons of the CNS; its symptoms -- tremors, stiffness, and difficulty with walking, balance and coordination -- develop gradually over years, and a person's hands may visibly shake or 'rattle' while trying to hold something steady. Alzheimer's disease, the most common form of dementia, has an incidence that rises with age, showing itself as loss of cognitive functioning -- thinking, remembering, reasoning and behaviour -- severe enough to interfere with daily life; …