sentences:  The other two sensory nuclei are the chief sensory nucleus mediating conscious facial touch and the spinal trigeminal nucleus, mediating pain and temperature in the head, and is of importance in headache.The trigeminal motor nucleus innervates the muscles of mastication, mylohyoid, anterior belly of digastric, tensor veli palatini, and tensor tympani.Unlike many nuclei within the central nervous system (CNS), the mesencephalic nucleus contains no chemical synapses but are electrically coupled.