The eyes and inner ear must work together smoothly to allow the eyes to stay fixed on an object while the body is moving. Reflexes exist within the nervous system that link the eyes with the vestibular system (vestibulo-ocular reflex). This link is modified in space. Drs. Gilles Clement and Bernard Cohen are using a rotating chair (the off-axis rotator) to study how microgravity changes the vestibulo-ocular reflex and the effects this may have on spatial orientation and postural function.