Individual recognition from biological motion: Structural versus dynamic information

A familiar person can be recognized by the way he or she moves. We investigated this ability using point-light displays of seven different walkers shown from three different viewpoints. Each observer was presented with only one viewpoint and was trained to name the walkers. During training, diagnostic information was gradually reduced by normalizing the stimuli with respect to their size, their shape, and their speed. We evaluated the influence of those manipulations on the learning curve and on the performance in separate non-reinforced test sessions. Finally, the fully normalized walkers were shown in different orientations in order to test the observer’s ability to generalize to new viewpoints.