Figure 3. Results from experiment 1.

Biases (a) and thresholds (b) are shown for four observers when the yoked target football was presented alone (red) or in the ‘rich cue’ environment (green) which consisted of a static background and adjacent static objects (see figure 1a and d). Biases and thresholds are given as rotation gains (see figure 2) and hence have no units. The white diamonds show the average (root mean square) threshold for individual runs (see text and figure 4 for explanation).