Fly trajectory metrics for endogenous locomotion (gray bars), Buridan's paradigm with narrow stripes (white bars) or wide stripes (striped pattern).

A. In the presence of visual targets, the fly shows more walks between the stripes than in their absence. B. Median stripe deviation is different in the three groups. Red line denotes the value for random walks C. Centrophobism during pauses is still present in all three groups. D. Centrophobism while moving is eliminated by narrow stripes. E. Median speed is not significantly affected by visual targets. F. The number of pauses is lower in the wide stripe condition as compared to the two other conditions. Asterisks denote significant differences after a MANOVA analysis. Bars represent means and error bars standard errors, n = 20 in each group.