Brain disease leading to mental illness: a concept initiated by the discovery of general paralysis of the insane.

In the early 19th century the prevailing alienist (psychiatrists') view was that organic lesions did not cause madness. The history of general paralysis of the insane (GPI) rests on four early publications which changed this concept: Haslam's Observations on insanity, Bayle's Recherches sur l'arachnitis chronique, Calmeil's De la paralysie considérée chez les aliénés, and Esmarch and Jessen's Syphilis und Geistesstörung. Haslam's account is unconvincing, but Bayle's report linking mental alienation with organic brain disease was a polemic that opposed established teachings. Calmeil and Delaye emphasised clinicopathological correlation and stressed the importance of white matter disease in causing dementia. GPI was to prove a crucial starting point in which the causes of mental illness were slowly transformed from psychogenic disturbances of mind and spirits to organically determined diseases.