Pick's disease is a form of dementia characterized by a slowly progressive deterioration of social skills and changes in personality leading to impairment of intellect, memory, and language. Although the disease varies greatly in the way it affects individuals, there is a common core of symptoms among patients which may be present at different stages of the disease. These symptoms include loss of memory, lack of spontaneity, difficulty in thinking or concentrating, and disturbances of speech. Other symptoms include gradual emotional dullness, loss of moral judgment, and progressive dementia. Although the disease usually affects individuals between the ages of 40 and 60, the age of onset may range from 20 to 80. The cause of the disease is unknown.