Transcranial magnetic stimulation (TMS) is a non-invasive and painless method of stimulating neural activity within the corticospinal system (Tazoe and Perez, 2015). A coil is placed on the scalp over an area of interest (e.g. motor cortex) to generate an electromagnetic field, which alters electrical fields within the brain (Peterchev et al., 2012; Tazoe and Perez, 2015). Accordingly, this causes a change in neural membrane polarization, leading to an increase in neuron activity, transmission and activation of neural networks (Peterchev et al., 2012). This activity can be easily assessed using electromyographic recording electrodes to detect motor-evoked potentials (MEPs) – the output of the primary motor cortex (Tazoe and Perez, 2015). TMS may be applied as a single pulse or repetitively (rTMS) to elicit long-lasting significant improvements in aspects of sensory and motor function (Tazoe and Perez, 2015). The three main applications of rTMS in SCI are focused on improving sensory and motor function impairments, spasticity and neuropathic pain (Tazoe and Perez, 2015).
The methodological details and results from five TMS studies are listed in Table 16.