To study the movements of infants and children, or their parents, we make use of motion tracking. With this method, we accurately register how certain body parts (for example, the arms) move. To achieve this, we place small reflective markers on the body parts we aim to track. Using special infrared cameras, we are able to precisely measure the location of these markers.
We can use this technique, for example, to study the motor control of a one-year-old or to investigate how parents adjust their movements when interacting with a young child.