Perceiving ambiguous point-light actions

Jan Vanrie, Mathias Dekeyser & Karl Verfaillie

Laboratory of Experimental Psychology, K.U. Leuven

Without occlusion, a point-light figure constitutes a perfectly ambiguous stimulus: From all viewpoints, multiple interpretations are possible concerning the figure’s depth orientation. In a first experiment, we demonstrated that a bi-stable point-light walker can indeed be perceived in different orientations. However, we also observed a clear bias to interpret the walker as facing the viewer instead of facing away from the viewer. Another experiment, with a point-light figure walking backwards, indicated that this tendency was not due to the perceived direction of articulatory motion, but might be a more general property of point-light figures. Subsequently, we performed a third experiment, using several point-light actions. The results showed that the facing-bias depends on the actual movement pattern.