Rotational movement (circling) in normal humans: sex difference and relationship to hand, foot and eye preference.

An endogenous asymmetry in striatal dopaminergic function has been identified in rats, and related to spontaneous and drug-induced circling (rotation, turning). We have developed an electronic device for measuring in humans the same kinds of rotational movements observed in rats. Our data indicate that, without being aware of the type of information being obtained, normal men and women rotate preferentially to the left or to the right during a routine day. Women had higher average rates of rotation than men. Males that were consistently right-sided (left-hemisphere dominant) for hand, foot and eye dominance rotated more to the right than to the left, whereas left-hemisphere dominant females rotated more to the left than to the right. Subjects tested on two occasions, 6 weeks apart, exhibited consistent (significantly correlated) rotational preferences--this was much more evident in left-hemisphere dominant than in mixed dominance individuals. In view of similar animal data, the device used in this study may become a useful and objective means for obtaining quantitative information regarding the status of basal ganglia function in humans.