Saccadic latencies for achromatic and chromatic targets

The purpose of this experiment was to compare saccadic latencies for supra-threshold achromatic and chromatic targets of equivalent contrast. Two experiments were performed. In the first experiment, subjects made saccades to horizontal and vertical chromatic (red, green, and blue) targets. The luminance of these targets was matched to the luminance of the white background. In the second experiment, subjects made saccades to horizontal and vertical achromatic targets whose luminance contrast was matched to the chromatic contrast of the targets in the first experiment using the CIE L*a*b* color space. In the first experiment, the saccadic latencies did not vary significantly (p = 0.074) for the different target colors. However, in the second experiment the mean latency for achromatic targets (268.6 ms +/- 53.1) varied significantly from the pooled latency for color targets (318.4 ms +/- 75.1).