Best Answer: St. Augustine (Florida) is the oldest continually occupied European settlement in the continental United States, only San Juan, Puerto Rico predates the city as the oldest settlement within the territory of the United States.
Finally in 1980 the American Psychiatric Association officially recognized multiple personality disorder as a genuine emotional illness. Today, MPD is a relatively popular diagnosis with 20,000 cases recorded between 1980 and 1990. Researchers currently believe that from 0.01-10% of the general population has this mental illness.
Neugarten (1964), investigated the personality development of adults aged 40 to 80 over a ten-year period in Kansas City, Missouri. Gazzaniga (1970), described the behavior of the split-brain patient W. J. who had had his cerebral hemispheres separated in order to control epilepsy.