Eye blink responses and an eye movement response were both present in the blind subject, the latter elicited by having the patient imagine himself looking at his index finger raised 30° above or below the horizontal. Sample responses are shown in Fig. 4. Neither dark adaptation nor exposure to the brightest available light altered the amplitude of his movement or eye blink responses. Cross correlation of the 2 curves was 090. Of particular practical significance, however, was the finding that the variation associated with eye movement responses was significantly greater than that of the eyeblink responses (t test for homogeneity of variance of related measures, t= 30.6, p