Spatiotemporal biases in localization and interception: common underlying mechanisms?

Human perception of space, time and motion is subject to several biases. Lab studies showed such effects in psychophysical judgements of location, but also in action-tasks, like predicting motion and intercepting. Given that similar underlying processes have been proposed for some of these biases, we tested for a shared mechanism by correlating them across observers. Using the classical implied motion sequence, participants either indicated the remembered location of an intermittently presented dot consistently ‘moving’ from one location to the next, or intercepted a predicted future location of the same intermittently presented dot. We examined whether the errors in those tasks are associated by correlating i) the overall amount of overshooting, and ii) the effect of temporal manipulations of the ‘jump’ duration on these biases across participants. We found two medium correlations indicating that these two biases are indeed related to each other. Participants who show a larger effect in one task also show a larger effect in the other task, and participants with larger proneness to temporal features show them consistently across both tasks. This suggests a shared underlying mechanism, and theoretical implications are discussed.