No abstract

SUMMARY Eight adult volunteers had EEG recordings and serial serum prolactin estimations performed both before and after a session of transcutaneous stimulation of the central motor pathways using the technique of Merton and Morton. No significant changes in either the EEG traces or in the serum prolactin values were detected.The ability to study function in central motor pathways, using techniques of transcutaneous stimulation through the intact scalp, is an important recent development in clinical neurophysiology. In a conscious subject, a single large shock from a purpose-built device is applied to the scalp over the motor cortex with disc or pad electrodes. The resulting contraction in peripheral muscles can be recorded using conventional apparatus.' Studies on normal adults23 and on patients with multiple sclerosis4 have recently been published.The technique appears to be safe, and no adverse effects have been reported from amongst the several hundred subjects who have been tested. In addition, some of the original investigators have themselves received hundreds of stimuli without ill-effect. However, there have been no studies to delineate possible transitory physiological effects of transcutaneous stimulation.Electroencephalograms (EEGs) taken immediately after unilateral electro-convulsive therapy (ECT) show marked slowing (1-4Hz activity reaching