The effect of loading on position sense in the tongue.

The position sense of the tongue and aftereffects on the position sense subsequent to loading were directly investigated. Nine subjects judged the straightahead with the tongue before and after straining laterally with the tongue against the horizontal force induced by a 29.5-g weight. Two of these subjects also participated in the experiment after the surface of the tongue had been anesthetized. Prior loading of the tongue biased the subjects' subsequent judgment of the straight-ahead; following loading, the tongue was placed farther in the direction of the previous effort. The results are discussed with reference to postcontraction effects from experiments on loading the limb and eye.