 Electrical brain stimulation was first used in the first half of the 19th century by pioneering researchers such as Luigi Rolando (1773–1831) and Pierre Flourens (1794–1867), to study the brain localization of function, following the discovery by Italian physician Luigi Galvani (1737–1798) that nerves and muscles were electrically excitable.The stimulation of the surface of the cerebral cortex by using brain stimulation was used to investigate the motor cortex in animals by researchers such as Eduard Hitzig (1838–1907), Gustav Fritsch (1838–1927), David Ferrier (1842–1928) and Friedrich Goltz (1834–1902).The human cortex was also stimulated electrically by neurosurgeons and neurologists such as Robert Bartholow (1831–1904) and Fedor Krause (1857–1937).