Marshall Hall (1790-1857), who graduated from the University of Edinburgh's Medical School in 1812, was considered one of the greatest physiologists of his day. He advanced knowledge in various areas of medicine, in particular elucidating the mechanism of reflex activity in 1833. Hall suggested that convulsive epileptic seizures arose from heightened activity in the afferent limb or the central component of the reflex arc. From 1838 onwards he developed the idea that reflex-mediated neck muscle spasm in seizures obstructed cerebral venous return, congested the brain and thus caused unconsciousness. Associated reflex-mediated laryngeal spasm then caused convulsing. This was the most comprehensive physiologically based explanation of the major features of the convulsive epileptic seizure then available. Hall subsequently advocated and employed tracheotomy to prevent epileptic convulsing. His idea was taken up, modified and made more acceptable by others, and for a generation was the widely acknowledged basis for interpreting epileptogenesis. However, from 1870 onwards it was superseded by John Hughlings Jackson's accumulating evidence that epileptic seizures often arose in the cerebral cortex