Special Visceral Efferent Nuclei
These nuclei are also called branchial efferent or branchiomotor nuclei. They supply striated (skeletal) muscle derived from branchial arches.
1. Themotor nucleus of the trigeminalnerve lies in the upper part of the pons, in itsdorsal part (Figs. 10.1, 10.2, and 10.3D). It is situated in the lateral part of the reticular formation, medial to the main sensory nucleus of the trigeminal nerve .
2. Thenucleus of thefacial nerve lies in thelower part of the pons and occupies a position similar to that of the motor nucleus of the trigeminal nerve. The spinal nucleus and tract of the trigeminal nerve lie lateral to it. (Figs. 10.1, 10.2 and 10.3C).
3. Thenucleus am-biguus lies in the medulla. It forms an elongated column lying deep in the reticular formation, both in the open and closed parts of the medulla (Figs. 10.1, 10.2 and 10.3A, B). Inferiorly, it is continuous with the spinal accessory nucleus. It is a composite nucleus and contributes fibres to the glossopharyngeal, vagus and accessory nerves.