CINGULECTOMY IN THE TREATMENT OF AGITATED MENTAL DEFECTIVES

　 (1) The effects of bilateral lesion of the anterior cingulate gyrus on agitated mental defectives were reported. The restless, impulsive and aggressive states were markedly relieved by the operation with-out apparent intellectual impairment.

　 (2) Electrical stimulation of the gyrus during the procedure failed to show mark-ed responses expected, possibly due to anesthesia. Photoelectric plethysmography before, during and after the procedure revealed remarkable influences of the area on peripheral circulatory conditions. Name ly, transient vasoconstriction immediately after the anterior cingulate lesion and subsequent pronounced vasodilatation, ap-pearing contralaterally to the side of the lesion.

　 (3) It was postulated that there are two kinds of circuits in the prosencephalon, ergotrope and trophotrope, in relation to-the ergotrope and trophotrope sectors of Hess. The anterior cingulate cortex, its posterior portion in particular, may well be regarded as one of the most important links of the ergotrope circuits. The effect of anterior cingulectomy could be explained on this basis.