On the possible causal relation between perceived spatial orientation and induced motion.

In 1994 Brooks and Sherrick showed that both the rod-and-frame effect and frame-and-spot-induced motion increase as the inducing frame is made larger. This suggests that change in perceived spatial orientation causes induced motion. Here it is argued that the rod-and-frame effect is more appropriately compared with induced rotation, which differs from frame-and-spot-induced motion in a number of ways. It is argued that the rod-and-frame effect may inhibit induced rotation.