Gall, Franz Joseph

(born March 9, 1758, Tiefenbronn, Baden—died Aug. 22, 1828, Paris, Fr.) German anatomist and physiologist, founder of phrenology. Convinced that mental functions reside in specific brain areas and determine behaviour, he assumed that the skull surface reflected development of these areas. The first concept was proved correct when Paul Broca located the brain's speech centre in 1861. The second was invalidated when it was found that the skull's thickness varies, so its shape does not reflect the brain's. Gall was the first to identify gray matter with active tissue (nerves) and white matter with conducting tissue.