| Red nucleus | |
|---|---|
 Transverse section through themidbrain showing the location of the red nuclei. Thesuperior colliculi are at the top of image and thecerebral peduncles at the bottom of image – both in section. | |
| Details | |
| Part of | Midbrain |
| Identifiers | |
| Latin | nucleus ruber |
| MeSH | D012012 |
| NeuroNames | 505 |
| NeuroLex ID | birnlex_1478 |
| TA98 | A14.1.06.323 |
| TA2 | 5898 |
| FMA | 62407 |
| Anatomical terms of neuroanatomy | |
Thered nucleus ornucleus ruber is a structure in therostralmidbrain involved inmotor coordination.[1] The red nucleus is pale pink, which is believed to be due to the presence ofiron in at least two different forms:hemoglobin andferritin.[2] The structure is located in themidbrain tegmentum next to thesubstantia nigra and comprises caudalmagnocellular and rostralparvocellular components.[1] The red nucleus and substantia nigra are subcortical centers of theextrapyramidal motor system.
In avertebrate without a significantcorticospinal tract,gait is mainly controlled by the red nucleus.[3] However, inprimates, where thecorticospinal tract is dominant, therubrospinal tract may be regarded as vestigial in motor function. Therefore, the red nucleus is less important in primates than in many other mammals.[1][4] Nevertheless, thecrawling ofbabies is controlled by the red nucleus, as is arm swinging in typical walking.[5] The red nucleus may play an additional role in controlling muscles of theshoulder and upper arm via projections of its magnocellular part.[6][7] In humans, the red nucleus also has limited control overhands, as therubrospinal tract is more involved in large muscle movement such as that for the arms (but not for the legs, as the tract terminates in the superior thoracic region of the spinal cord). Fine control of thefingers is not modified by the functioning of the red nucleus but relies on thecorticospinal tract.[8] The majority of red nucleus axons do not project to thespinal cord but, via its parvocellular part, relay information from themotor cortex to thecerebellum through theinferior olivary complex, an important relay center in themedulla.[1]
The red nucleus receives many inputs from thecerebellum (interposed nucleus and the lateral cerebellar nucleus) of theopposite side and an input from the motor cortex of thesame side.[9]
The red nucleus has two sets of efferents:[9]
