Rotating objects cue spatial attention via the perception of frictive surface contact

We report a new attentional cueing effect, which shows how attention models the physical force of friction. Most objects we see are in frictive contact with a 'floor', such that clockwise rotation causes rightward movement and counterclockwise rotation leftward movement. Is this regularity encoded in spatial orienting responses? In Experiment 1, seeing a clockwise-rotating 'wheel' produced faster responses to subsequent targets appearing on the right vs. left (and vice versa for counterclockwise rotation). Thus, when viewing a lone rotating wheel, we orient attention toward where we predict it will move next, assuming frictive floor contact. But what happens if the rotating wheel is seen touching another visible surface? In Experiment 2, rotational cueing was stronger for wheels touching a visible floor, was abolished for wheels near but not touching another surface, and reversed for wheels touching a ceiling. We conclude that the visual system makes an assumption of frictive floor contact, and rapidly analyzes visual cues to frictive contact with other surfaces, in order to orient attention toward where objects are likely to move next.