Trapezoid body

Brain: Trapezoid body
Image:Gray760.png
Terminal nuclei of the cochlear nerve, with their upper connections. (Schematic.) The vestibular nerve with its terminal nuclei and their efferent fibers have been suppressed. On the other hand, in order not to obscure the trapezoid body, the efferent fibers of the terminal nuclei on the right side have been resected in a considerable portion of their extent. The trapezoid body, therefore, shows only one-half of its fibers, viz., those which come from the left. 1. Vestibular nerve, divided at its entrance into the medulla oblongata. 2. Cochlear nerve. 3. Accessory nucleus of acoustic nerve. 4. Tuberculum acusticum. 5. Efferent fibers of accessory nucleus. 6. Efferent fibers of tuberculum acusticum, forming the striae medullares, with 6’, their direct bundle going to the superior olivary nucleus of the same side; 6’’, their decussating bundles going to the superior olivary nucleus of the opposite side. 7. Superior olivary nucleus. 8. Trapezoid body. 9. Trapezoid nucleus. 10. Central acoustic tract (lateral lemniscus). 11. Raphé. 12. Cerebrospinal fasciculus. 13. Fourth ventricle. 14. Inferior peduncle.
Latin	corpus trapezoideum
Gray's	subject #191 858
NeuroNames	hier-589
Dorlands/Elsevier	c_56/12260860

The trapezoid body is part of the acoustic pathway. It is a bundle of fibers and cells in the pontine tegmentum. It consists of fibers arising from the cochlear nucleus. A collection of nerve cells inside forms a trapezoid nucleus. The superior olivary nucleus is situated on the dorsal surface of the trapezoid body. Most nerve fibers pass directly from the olivary nuclei to the inferior colliculus.