{"pk":28844,"title":"Perception of Continuous Movements from Causal Actions","subtitle":null,"abstract":"We see the world as continuous with smooth movements of\nobjects and people, even though visual inputs can consist of\nstationary frames. The perceptual construction of smooth\nmovements depends not only on low-level spatiotemporal\nfeatures but also high-level knowledge. Here, we examined the\nrole of causality in guiding perceptual interpolation of motion in\nthe observation of human actions. We recorded videos of natural\nhuman-object interactions. Frame rate was manipulated to yield\nshort and long stimulus-onset-asynchrony (SOA) displays for a\nshort clip in which a catcher prepared to receive a ball. The\nfacing direction of the catcher was either maintained intact to\ngenerate a meaningful interaction consistent with causality, or\nwas transformed by a mirror reflection to create a non-causal\nsituation lacking a meaningful interaction. Across three\nexperiments, participants were asked to judge whether the\ncatcher’s action showed smooth movements or sudden changes.\nParticipants were more likely to judge the catcher’s actions to be\ncontinuous in the causal condition than in the non-causal\ncondition, even with long SOA displays. This causal\ninterpolation effect was robust to manipulations of body\norientation (i.e. upright versus inverted). These findings indicate\nthat causality in human actions guides interpolation of body\nmovements, thereby completing the history of an observed\naction despite gaps in the sensory information. Hence, causal\nknowledge not only makes us see the future, but also fills in\ninformation about recent history.","language":"eng","license":{"name":"","short_name":"","text":null,"url":""},"keywords":[{"word":"causality; causal action; motion interpolation;\nhuman action; human interaction"}],"section":"Papers with Poster Presentations","is_remote":true,"remote_url":"https://escholarship.org/uc/item/49d107s3","frozenauthors":[{"first_name":"Yujia","middle_name":"","last_name":"Peng","name_suffix":"","institution":"University of California, Los Angeles","department":""},{"first_name":"Nicholas","middle_name":"","last_name":"Ichien","name_suffix":"","institution":"University of California, Los Angeles","department":""},{"first_name":"Hongjing","middle_name":"","last_name":"Lu","name_suffix":"","institution":"University of California, Los Angeles","department":""}],"date_submitted":null,"date_accepted":null,"date_published":"2019-01-01T18:00:00Z","render_galley":null,"galleys":[{"label":"PDF","type":"pdf","path":"https://journalpub.escholarship.org/cognitivesciencesociety/article/28844/galley/18715/download/"}]}