ORIGINAL ARTICLE Movement kinematics affect action prediction: comparing human to non-human point-light actions Waltraud Stadler • Anne Springer • Jim Parkinson • Wolfgang Prinz Received: 18 July 2011 / Accepted: 29 February 2012 / Published online: 13 March 2012 Ó Springer-Verlag 2012 Abstract The influence of movement kinematics on the accuracy of predicting the time course of another individ- ual’s actions was studied. A human point-light shape was animated with human movement (natural condition) and with artificial movement that was more uniform regarding velocity profiles and trajectories (artificial condition). During brief occlusions, the participants predicted the actions in order to judge after occlusion whether the actions were continued coherently in time or shifted to an earlier or later frame. Error rates and reaction times were increased in the artificial compared to the natural condition. The findings suggest a perceptual advantage for movement with a human velocity profile, corresponding to the notion of a close interaction between observed and executed move- ment. The results are discussed in the framework of the simulation account and alternative interpretations are pro- vided on the basis of correlations between the velocity profiles of natural and artificial movements with prediction performance. Introduction In the present article, we take a closer look at the ability to predict full-body movement of a character with human shape but non-human movement kinematics. We are interested in action prediction on the kinematic level (see Grafton and Hamilton, 2007 for different levels to describe action), which implies predicting the course of a movement in space and time rather than predicting its goals or the intentions of the agent. Action prediction on the kinematic level is essential in the context of complementary inter- action. For instance, a handshake can only be successful if both partners engage in prediction to arrive simultaneously at the appropriate location. Would they be equally effective when shaking hands with a virtual character in a computer animation? On the kinematic level, certain regularities have been found to characterise human movement kinematics (Vivi- ani & Flash, 1995). More specifically, human movement tends to smoothness (minimum jerk; Flash & Hogan, 1985) and exhibits a typical relation between the curvature of the movement trajectory and the velocity described in the so called ‘‘two-third power law’’ (Lacquaniti, Terzuolo, & Viviani, 1983). This general rule applies to various kinds of human movement such as pointing (Lacquaniti et al., 1983), locomotion in space, as an example of full-body movement (Hicheur, Vieilledent, Richardson, Flash, & Berthoz, 2005) and foot movement during walking (Iva- nenko, Grasso, Macellari, & Lacquaniti, 2002). Electronic supplementary material The online version of this article (doi:10.1007/s00426-012-0431-2) contains supplementary material, which is available to authorized users. W. Stadler Á A. Springer Á J. Parkinson Á W. Prinz Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany W. Stadler (&) Department of Sports and Health Science, Human Movement Science, Technische Universita ¨t Mu ¨nchen, Georg-Brauchle-Ring 60-62, 80992 Munich, Germany e-mail: waltraud.stadler@tum.de A. Springer Faculty of Human Sciences, Cluster of Excellency in Cognition Sciences, Department of Sports and Exercise Psychology, University of Potsdam, Potsdam, Germany J. Parkinson Institute of Cognitive Neuroscience, University College London, London, UK 123 Psychological Research (2012) 76:395–406 DOI 10.1007/s00426-012-0431-2