Central motor conduction time to bulbocavernosus muscle: evaluation by magnetic brain stimulation and testing of bulbocavernosus reflex.

Magnetic brain stimulation and bulbocavernosus reflex (BCR) testing were performed to evaluate the central motor conduction time (CMCT) to the bulbocavernosus muscle (BC). In six healthy subjects CMCT ranged from 13.81 ms to 16.9 ms with a mean value of 15.77 ms (SD 1.38 ms). This equals a central motor conduction velocity of about 40 m/s, which can only be realized in fast conducting pyramidal tract fibres. Testing of pyramidal tract function by BC-CMCT might improve the diagnosis of male sexual dysfunction.