Fig. 4: Optimal sequential actions under perceptual, representational, and motor uncertainties predict seemingly sub-optimal cue-integration behavior in conflict conditions.

a Mean responses for conflict conditions for participants from Chen et al.¹⁶ (left) vs. simulated participants from our computational model (right) for an environment with three landmarks (top) and one landmark (bottom). b Optimal vs. empirical cue weights for participants from Chen et al.¹⁶ (left) vs. simulated participants from our computational model (right). Dots indicate individual (simulated) participants. Optimal cue weights were computed based on observed response variability in single cue conditions, whereas empirical cue weights were computed based on response proximity to either cue location in conflict conditions. Linear regression lines were fitted to (simulated) participants' cue weights for the two environments separately. c The reliance on landmark cues during homing is explained by the integration of egocentric landmark observations with subjective internal beliefs (see Supplementary Movie 4). Initially (t = 0), participants hold beliefs about their own location and that of landmarks. At t = 1, landmarks are covertly rotated, but participants' beliefs about their expected positions remain unchanged. By t = 10, participants turn around, encountering increased uncertainty in heading due to landmark rotation. The sight of landmarks recalibrates their internal heading estimate since they expect landmarks straight ahead, reducing uncertainty in position and heading. From t = 10 to t = 65, during homing, participants utilize their internal beliefs for path planning, employing landmarks to correct motor errors. This reduces positional uncertainty and variability in endpoints, though homing responses are biased. d Response bias in conflict conditions for (simulated) participants from Zhao & Warren¹⁵. Two-sided paired t-tests for angles 15°, 30°, 45°, and 90° with p-values for the proximal environment (n = 5) of 0.33, 0.93, 0.96, and 0.001, and for the distal environment (n = 6) of 0.06, 0.57, 0.71, and 0.25. Error bars show mean homing direction ± 1 SD. e Response variability in conflict conditions for (simulated) participants from Zhao & Warren¹⁵. Two-sided paired t-tests for angles 15°, 30°, 45°, and 90° with p-values of 0.85, 0.72, 0.46, 0.02 for the proximal environment (n = 5) and 0.85, 0.77, 0.41, 0.53 for the distal environment (n = 6). Error bars show mean homing variability ± 1 SD. Endpoint distributions are shown in Supplementary Fig. 14. Source data are provided as a Source Data file.