Motion perception and interpretation plays an important role in the human visual system. It helps us recognize different objects and their motion in a scene, infer their relative depth, their rigidity, etc. MLDs consist of bright spots attached to the joints of an actor dressed in black, and moving in front of a dark background. The collection of spots carry only 2D information and no structural information, since they are not connected.
Biological creatures move through the world with little apparent effort.
Ohya et al. Doc 9 Cyclic Motion Detection - Tsai, Shah et al. Allen et al. Doc 3 Aspects of the Kinematic Simulation of Human Movement - Calvert, Chapman et al. Doc 1 Recognition Using Motion and Shape - Rangarajan, Allen et al.