抄録
Convergence eye movement is slow adduction of both eyes normally elicited by an approaching visual target as a part of the near response (convergence eye movement, lens accommodation and pupillo-constriction), one of the cerebral reflex. While the most important cue for convergence eye movement is binocular disparity, convergence eye movement before target movements (anticipatory convergence) have been also reported in cats (Toda et al., 2006) and human (Kumar et al., 2002). In this study, we used unseen target to evoke and examine pupil reaction of anticipatory convergence in human. The subjects are nine healthy human (all male, 22 to 64 year-old, five are naiive to the purpose of the experiment). A video eye tracker (30fps) was used to record positions and diameters of both pupils. The visual targets were two LEDs at the front of the subject with distances of 114cm and 24cm. They were alternatively turned on and off in a regular timing (1.6 to 4Hz). The room was darken enough (under 1lx) to make both LEDs were unseen by the subject. Anticipatory saccadic convergence were found in all nine subject and differences between mean onset times of convergence eye movement and pupillo-constriction were significantly elongated in anticipatory convergence than in case of normal convergence. Reflecting functional segregation in the cerebral near response controllers, these results suggest that convergence eye movement system is more directly affected by higher centres corresponding to anticipation. [J Physiol Sci. 2008;58 Suppl:S196]
