Possession trance in a semi-urban community in Sri Lanka.

A survey of possession trance states in a semi-urban population of 7653 identified 37 subjects. The manifestations of the trance, and its course and outcome are outlined. The characteristics of the subjects, including presence of psychiatric disorder, are compared with that of the total population, and significant differences are noted. Four psychodynamic syndromes observed are described with illustrative case vignettes. The functions subserved by possession behaviour are reviewed, and comparisons are drawn between personal possession, ritual possession, and altered states of consciousness in Western society.