A compact equipment package for vestibular experiments during spaceflight.

A compact measurement and stimulus equipment package for vestibular testing is described. The package is designed on a modular concept so that a customised version can be assembled for each experimental situation. Although primarily conceived for space-related research, the equipment has also been introduced successfully into the clinical diagnostic procedure. An essential function of the equipment is the recording and evaluation of eye movements. This is performed by a video-based measurement system which permits evaluation of horizontal, vertical and torsional components of eye movement. Objective testing of the vestibulo-ocular reflex in all three orthogonal planes is therefore possible. Furthermore evaluation of the otolithic function in weightlessness is made feasible by the possibility of measuring dynamic ocular counterrolling. Some applications of the equipment are described.