Auricular branch of vagus nerve provide innervation of the external auditory canal. So mechanical stimulation of ear canal while cleansing it cause stimulation of this nerve branch of vagus nerve and may induce cough. The auricular branch of vagus nerve passes through the mastoid canaliculus and through a space between the mastoid process and the tympanic pa of the temporal bone to the external ear and external auditory canal. The ear canal receives sensory fibers from the glossopharyngeal nerve through its communicating branch with the vagus nerve.