Transitional Nerve: A New and Original Classification of a Peripheral Nerve Supported by the Nature of the Accessory Nerve (CN XI)

Figure 7

In amphibians, the accessory nerve continues to exit with the glossopharyngeal-vagus complex, however the nucleus has seperated in many species and is located within the spinal column. The accessory nerve innervated the cucullaris musculature which is associated with neck movement and feeding behavior. The accessory nerve is believed to have a universal presence in amphibians. The accessory nerve arises from a nucleus that overlaps portions of the upper cervical nerves. The nerve fibers exit via the IX, X, XI complex.