James A. (Jim) Pawelczyk, payload specialist, participates in a sensory motor and performance test by using a simple, but effective, ball-catching experiment which evaluates the ability of the central nervous system to accept and interpret new stimuli in space. Astronaut Dafydd (Dave) R. Williams, mission specialist representing the Canadian Space Agency (CSA), is in the background. The experiment uses the kinelite system, an apparatus developed by the Centre National d'Etudes Spatiales (CNES or the French Space Agency).