pects of the manual tilting task facilitated imagery performance. As indicated in Fig. 1, the judgment
task differs from the manual tilting task in that it does not provide any visual information about the
glass movement that could serve as a reference frame for the imagination of the water level. In addition,
the judgment task does not provide any motor information about the tilting movement because
there is no active ‘‘hands-on” movement taking place. This implies that the judgment task also lacks
haptic information about the glass diameter, and this could make the dimension less salient. The following
experiments were designed to further probe the question of which one of these task differences
accounts for the observed performance dissociation. They tested whether not executing the
movement (Experiment 2) and not seeing the tilting movement (Experiment 3) would reduce performance
in the manual tilting task.