title: The optic trajectory is not a lot of use if you want to catch the ball.
abstract: According to linear optic trajectory (LOT) theory, fielders use the direction of curvature of theoptic trajectory to control the way they run to intercept the ball. Data presented by D. M. Shaffer and M. K. McBeath (2002) as support for LOT theory show that the optic trajectory of balls that will fall behind the fielder provide the cue that LOT theory predicts would send the fielder running forward, not backward. In this article, the authors show that watching these balls would provide the fielder with the cue that the optic acceleration cancellation (OAC) theory of interception predicts would send the fielder running backward. It appears that the fielders studied by Shaffer and McBeath were following the cue predicted by OAC theory, not that predicted by LOT theory.
authors.affiliation: Department of Experimental Psychology, Oxford University, Oxford, United Kingdom. peter.mcleod@psy.ox.ac.uk
authors.forename: Peter
authors.initials: P
authors.lastname: McLeod
authors.forename: Nick
authors.initials: N
authors.lastname: Reed
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Dienes
mesh_terms: D003463:Cues; D005403:Fixation, Ocular; D006801:Humans; D009039:Motion Perception; D011582:Psychological Theory; D011597:Psychomotor Performance; D013997:Time Factors; D014796:Visual Perception