Perception of Body Tilt

In the experimental runs the subject sat in a chair on a platform about five feet square. The platform could be tilted either by the experimenter or by manipulations on the part of the subject. The amount of tilt was controlled by means of a hydraulic system, which was relatively silent. The subject was carefully blindfolded during all trials. For each trial the experimenter set the platform at a pre-determined angle of tilt and then signalled the subject to bring himself back to the level position. Measurements were made for both longitudinal (forward-backward) and lateral (sidewise) tilt. The principal finding was that errors of adjustment were less for lateral than for longitudinal directions of tilt