Catecholamines and opioid peptides oncrease in plasma in humans during possession trances

Naturally induced possession trances have been observed in healthy people of many societies. The neurophysiological basis of this phenomenon remains unknown, however, because of the dif®culty in accessing subjects in trances due to their sacred context. In the present study, we measured the plasma levels of several neuroactive substances from subjects exhibiting or lacking possession trance characteristics during Balinese ded- icatory dramas under natural conditions. The trance group exhibited signi®cant increases in plasma concentrations of noradrenaline, dopamine and â-endorphin, compared with controls who performed the same actions as the trance group. The present ®nding suggests that catecholamines and opioid peptides are involved in possession trances