Brain plasticity, intended as the pattern of functional and structural changes in responses to environmental physiological or pathological events, is underlined by several mechanisms. Besides cortical changes such as changes in synaptic and representational patterns, morphologic and functional changes at the neuronal level have been hypothesised. Among the non-invasive techniques utilised in humans, electrophysiological methods allow description of the temporal dynamics of cortical activation and their inhibitory or excitatory functional significance. We will focus on the main applications of these techniques, mainly electroencephalography and transcranial magnetic stimulation, in the study of brain plasticity in humans following motor learning or lesions of the nervous system.