Transcranial magnetic stimulation of the sensorimotor cortex alters kinaesthesia

Tendon vibration is known to evoke perception of illusory movements, together with motor responses in the muscles antagonistic to those vibrated. In the present study, we assessed the perceptual and motor effects of transcranial magnetic stimulation of the sensorimotor cortex during illusions of hand movements evoked by vibration of wrist muscle tendons. The results showed that transcranial magnetic stimulation could accelerate or decelerate the illusory movements, depending on the site and intensity of magnetic stimulation. Whenever transcranial magnetic stimulation decelerated illusory movements, motor responses decreased, whereas whenever it accelerated illusory movements, motor responses increased. We conclude that motor responses associated with movement illusions have a cortical stage, because they are affected by experimentally induced disruption of activity in intracortical networks.