Table 1. Contrasts of right versus left go trials.

Anatomical location	Cluster size	Z value	XYZ (mm)
Go right minus left
L ventral occipital	189	4.29	-4 -82 -4
L dorsal occipital*	443	4.46	-24 -84 22
L middle temporal	18	3.35	-44 -74 -10
Go left minus right
R ventral occipital	249	4.34	12 -82 -8
L dorsal occipital*	150	4.07	-22 -104 6
L dorsal occipital*	54	3.85	-8 -92 18

^*The left dorsal occipital activations most likely reflect the presence of the visible light associated with the light-source for the near-infrared eye-tracker (ASL 504a, Applied Science Laboratories), which always appeared in the bottom right visual field and therefore shifted position along the retina in different directions for upper-left and upper-right executed saccades (while always remaining in the bottom-right quadrant, due to its eccentricity of approximately 14 degrees). Note that such retinal changes due to saccades did not arise on no-go trials, which provide a further critical test of our hypotheses, see main text.