POST-MOVEMENT BETA-SYNCHRONIZATION - A CORRELATE OF AN IDLING MOTOR AREA

Post-movement beta (around 20 Hz) synchronization was investigated in 2 experiments with self-paced finger extension and flexion and externa lly paced wrist movement. The electrodes were fixed over the sensorimo tor area in distances of 2.5 cm. It was found that after a brisk finge r movement the desynchronized beta rhythm displayed a fast recovery an d a short-lasting synchronization within 1 sec. This post-movement bet a synchronization was maximal over the contralateral hemisphere and lo calized slightly more anterior to the maximal desynchronization of the hand area mu rhythm. The post-movement beta synchronization is interp reted as a correlate of ''idling'' motor cortex neurons.