[Effect of 7-day dry immersion on the mechanisms of ocular saccadic movements generation]

To evaluate the impact of prolonged support deprivation on the mechanisms of ocular saccadic movement generation, four volunteers were tested on the eve of 7-d dry immersion and on the completion day. The task consisted of tapping random light stimuli emerging on the periphery of sensory screen. During testing, the head was kept in a fixed position. To tap stimuli, human subject was either to touch a respective spot on the screen with a finger with gaze shifting and fixation accompanying coordinated hand movement (1) or to press the mouse key after gaze fixation on stimulus (2). Movements of the eyes were registered and analyzed in the infrared frequency of 200 Hz. It is maintained that the similar impact of immersion on the peak saccade velocity-amplitude ratio no matter how stimuli were tapped suggests saccade acceleration after immersion in consequence of the direct effect of prolonged support deprivation.