Visual Action Recognition Study: Orientation Specificity in Mental Representations of Upright and Inverted Biological Motion

Research on biological motion, using point-light displays to present the motions, have been unravelling what information factors are still embedded in those impoverished stimuli and which of these factors are essential in visual processing of biological motion. Earlier studies suggest that orientation is a crucial factor in biological motion processing. The short-term priming experiment presented in this paper will further investigate the legitimacy of the primacy of orientation and suggest different solutions based on contradicting findings in previously published studies. In a serial two-choice reaction-time task, participants were presented with a patch-light display of a human engaged in one of three possible actions: climbing up a rope, jumping jacks, and walking. Participants had to identify the in-plane orientation of the human figure emerging from the moving patch-lights. Reliable facilitation effect was established for transitions containing same-oriented upright trails and same-oriented inverted trials. Interestingly, transitions of same-oriented upright trials produced significantly greater facilitation effect than transitions of same-oriented inverted trials