In 1908, Diefendorf and Dodge1 reported "An Experimental Study of the Ocular Reactions of the Insane." Using the corneal reflection method, with the Dodge photochronograph, they recorded the velocity of ocular movements, the reaction time to new peripheral stimuli and the ocular pursuit reactions. They found that the speed of ocular movements does not correspond with the degree of depression or of manic excitement in the manic-depressive cases. However, in extreme cases of manic excitement the speed was greater than normal, and in markedly depressed cases it was less than normal. Cases of dementia praecox and of dementia paralytica showed abnormally rapid ocular movements; cases of chronic epilepsy, notably slow ones. In the manic-depressive psychoses the same tendency held true for the ocular reaction time to new peripheral stimuli as was noted in measurements of the speed of ocular movements. In testing pendular pursuit reactions they observed a typical