Facilitatory motor cortex plasticity induced by paired associative stimulation in the awake rhesus monkey

Externally induced neuroplastic changes of cortical excitability may be of therapeutic value in several neuro-psychiatric disorders. However, potent stimulation paradigms leading to therapeutically relevant after-effects are required. In order to enable the shaping of advanced stimulation protocols we developed a primate model of transcranial magnetic stimulation (TMS). To evaluate the model, we measured the after-effects of paired associative stimulation on motor-cortical excitability using focal TMS. Two male rhesus monkeys were trained to tolerate the fixation of the forearm and to relax the hand muscles. Sur…