(A−I) Examples of sequential changes in position of 9 different pixels (each 2.5 × 2.5 nm), where the center of mass positions of corresponding different particles are located. In each frame, the pixel positions were recorded 3 times, i.e., before ATP application, during ATP application, and after complete exhaustion of applied ATP. The changes in the pixel position in the first (red), second (blue), and the third record (yellow) represent the changes in the myosin head position before ATP application, during ATP application, and after complete exhaustion of ATP. Direction of each myosin head movement is indicated by arrows. Note that myosin heads return towards their initial position after exhaustion of ATP. From Sugi et al., [6].