Abstract
Causality is a unique feature of human perception. We present here a behavioral investigation of the influence of physical causality during visual pursuit of object collisions. Pursuit and saccadic eye movements of human subjects were recorded during ocular pursuit of two concurrently launched targets, one that moved according to the laws of Newtonian mechanics (the causal target) and the other one that moved in a physically implausible direction (the non-causal target). We found that anticipation of collision evoked early smooth pursuit decelerations. Saccades to non-causal targets were hypermetric and had latencies longer than saccades to causal targets. In conclusion, before and after a collision of two moving objects the oculomotor system implicitly predicts upcoming physically plausible target trajectories.
Highlights
IntroductionIn a natural scene the illumination is expected to come from above
The visual world is organized according to a set of priors (Seriès and Seitz, 2013)
Dependent variables measured and statistical analysis We analyzed saccadic reaction times and saccadic gain defined as the ratio of initial position error to the center of
Summary
In a natural scene the illumination is expected to come from above Another essential set of priors concerns the laws of physics. Humans experience cause-effect relationships even during the observation of very simple collisions referred to as ‘launching events’ (Michotte, 1946/1963). In these events a moving object, referred to as the launcher, makes contact with a stationary one, referred to as the target that subsequently starts to move. Human observers quickly attribute physical causality to this type of event if the trajectories of the objects are in agreement with the laws of mechanics (Young and Sutherland, 2009; Young and Falmier, 2007). Gestalt psychology suggested that causality perception is processed implicitly by a rapid pre-attentional mechanism that is encapsulated within the early visual system (see e.g. Wagemans et al, 2006)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.