Figure 3. Short-distance (SD) and long-distance (LD) sampling strategies for texture discrimination.

A and B) Examples of SD sampling (A) and LD sampling (B) during smooth-grooved discrimination (Rat G5R2). Video frames were taken from underneath the rat. Dashed line, 2 mm from surface. LD trials were defined as trials in which the nose remained >2 mm from surface during all frames of sampling. C) Example of LD sampling during sandpaper discrimination. Dashed line, 2 mm from surface. D) Fraction of LD trials for rats performing smooth-grooved and sandpaper discrimination. E) Discrimination accuracy during LD and SD trials for smooth-grooved discrimination (left) and sandpaper discrimination (right, compiled for P150 vs. P1500 or P1200 discrimination). Asterisks, significant differences from chance (binomial exact test) or between grouops (two-sample equal proportion test). ns, no significant difference.