Safety and Feasibility of St. Mark's Electrode for the Hypoglossal Nerve and Cortico-lingual Pathway Study

The possibility of registering the M-response and the motor evoked potential (MEP) from the muscles of the tongue by using the St. Mark's electrode will be evaluated. The safety of method will be confirmed. Registered parameters will be compared with other known methods and comparative effectiveness of proposed method will be determined. The study will involve healthy volunteers without clinical symptoms of hypoglossal nerve and cortico-lingual pathway lesions and without surgical interventions in the tongue .The volunteers will be examined once for the parameters of the amplitude and latency of the M-response and MEP, as well as the difference between these indicators at different sides of the examination during nerve conduction study (NCS) and transcranial magnetic stimulation (TMS) of the hypoglossal nerve and the cortico-lingual pathway.