Stimuli and postures. Image (a) shows an example for a ‘left’ target from the avatar's perspective at 110° (clockwise angular disparity), image (b) shows an example for a ‘right’ target at 160° (anticlockwise), and image (c) shows an example for a ‘visible’ target at 60° (clockwise). In the figure, the target hemisphere is indicated by a brighter shade than the other three, whereas in the experiment colour stimuli were employed and the target changed colour from grey to red. Images (d(i)(ii)) show the two possible postures of the participant: body turned either (i) clock- or (ii) anticlockwise, while gazing straight ahead. The posture of the participant was therefore either congruent or incongruent to the direction of mental rotation on a particular trial.