History of Evoked Potential Recording in Humans

In 1875 Richard Caton at the Royal Infirmary School of Medicine in Liverpool, while searching for the cerebral counterpart of du Bois-Reymond’s action potential in nerve, not only found it, but, recording bipolarly with a Thomson’s galvanometer from cerebral cortex in animals, noticed that there was a continuous waxing and waning of cerebral potentials19 Superimposed on those waves Caton found potential swings related to sensory stimulation and realized that these were a sign of impulses reaching the brain from the periphery. In the following years, he was able to find responses to stimulation of limbs and to light stimulation. After Caton, Beck5; in Cracow, and Danilewsky28 and Larionov61 in St. Petersburg were successful in recording potential related to light and sound. Because they had no cameras, their findings were presented by verbal descriptions or as sketches. Thus, the potentials evoked by peripheral stimulation had already been discovered when the first pictures of cortical activity and sensory evoked potentials in animals were published by Neminsky in 1913 (Fig. 1). Detailed information on those early workers can be found in Rusinov and Rabinovich82, and in Brazier12,13.