Prediction of clinical efficacy of zopiclone by utilizing two psychophysiological tools in healthy volunteers.

Abstract

The clinical effects of zopiclone were predicted by using two psychophysiological tests: the averaged photopalpebral reflex and the frontal midline theta activity. Zopiclone at 5 and 10 mg showed a rapid, dose-dependent, moderately lasting prolongation of the latencies of the averaged photopalpebral reflex related to the lowering of the arousal level. Diazepam 5 mg increased markedly the frontal midline theta activity, the appearance of which seems to be related to the relief from anxiety, while zopiclone 10 mg only slightly modified the frontal midline theta activity. The results suggest that zopiclone possesses a potent hypnotic effect, whereas its anxiolytic potential in humans is probably low.