Geschwind changed to the Department of Social Relations and studied a combination of social/personality psychology and cultural anthropology.
At this time, his clinical interest in aphasia developed into his lifelong study of the neurological basis of language and higher cognitive functions.
In 1969, he was chosen as Harvard Medical School's James Jackson Putnam Professor of Neurology, a position previously held by his old mentor, Derek Denny-Brown.
At Harvard he continued to research aphasia and epilepsy, as well as dyslexias, the neuroanatomy of cerebral lateral asymmetries, and other areas of neurological dysfunction.
He also credited with the discovery of Geschwind syndrome, which describes an interictal behavior pattern seen in some people with temporal lobe epilepsy.
In later years, Geschwind worked with a number of neurologists to whose future research careers in behavioral neurology he gave significant direction; among these were Albert Galaburda,[2] Kenneth Heilman, Elliott Ross, and David N. Caplan.
Several of his trainees went on to train other neurologists in behavioral neurology, including Albert Galaburda,[2] D. Frank Benson, Antonio Damasio, Marsel Mesulam, Kenneth Heilman, and Elliott Ross.