The National Institute of Neurological Disorders and Stroke (NINDS), the National Institute on Aging (NIA), the National Institute of Mental Health (NIMH) and the National Heart, Lung, and Blood Institute (NHLBI) invite applications for studies on the plasticity and behavior of human stem cells, and regulation of their replication, differentiation and function in the nervous system. Because of their ability to generate neurons and glia, stem cells are promising candidates for the development of cellular and genetic therapies for neurological disorders, including congenital, neurodevelopmental, neuropsychiatric and neurodegenerative diseases, as well as neuroregulatory problems in heart, lung, and blood diseases, and sleep disorders.