sentences:  Supranuclear motor innervation of the facial musculature is difficult to examine because the circuitry is quite complex, only a few cases are described in literature of central facial palsy and the absence of bilateral perioral muscle responses after TMS of the affected hemisphere.EMG responses are often used to observe the upper facial muscles, however, it is difficult to elicit by TMS, which often works by examining the motor cortex and recording the motor stroked potentials.At high stimulation strengths, this often excites the trigeminal sensory afferents and triggers a blink reflex.