Cortical and spinal motor excitability during the transcranial magnetic stimulation silent period in humans.
WJ Triggs, D Cros, RA Macdonell, KH Chiappa, J Fang, BJ Day
Brain Res | Published : 1993
We investigated the electromyographic silent period in abductor pollicis brevis (APB) and flexor carpi radialis muscles following transcranial magnetic stimulation of human motor cortex. In APB, we measured cortical stimulation silent period (CSSP) duration as a function of stimulus intensity, motor-evoked potential (MEP) amplitude and muscle twitch force. We used peri-stimulus-time histograms to study the effect of cortical stimulation on single-motor unit firing patterns. We compared F-waves, H-reflexes and magnetic MEPs elicited during the CSSP to control responses elicited at rest and during voluntary contraction. CSSP duration depended on the intensity of cortical stimulation. However, ..View full abstract