The motor programs of monkey's saccades.

In this report we studied if the visual input by itself or a visual input with an attentional meaning may modify the velocity profiles of saccades. One monkey (Macaca nemestrina) was trained to perform visual fixation and make saccades to visual targets. We analized the velocity profiles of spontaneous saccades in dark and in laboratory light, and of visually guided saccades. We found three different velocity profiles: symmetrical, asymmetrical and irregular. The normalized frequency distribution of the three different velocity patterns displayed no difference between the two rest conditions, contrary, in the work condition, the irregular profiles were absent. These results may suggest that only a visual input with an attentional meaning may modify substantially the motor program of saccades