Anatomical structure consisting of a discrete aggregate of neuronal soma[GO][GO_REF:0000021].

Proposed CUMBO def from MM: A subcortical part of the nervous system consisting of a relatively compact group of cells that is distinguishable histologically that share a commonality of cytoarchitecture, chemoarchitecturel and connectivity. (comments: I put in 'subcortical' because I don't think we consider either the cerebellar cortex or cerebral cortex to be nuclei. Some people distinguish between a nucleus and a laminar structure (see Wikipedia definition). However, there are structures identified as nuclei that are laminar, e.g., lateral geniculate nucleus, although they are not laminated in all species. Also, I put in 'relatively compact' and 'distiguishable by histology' because we have groups of cells, e.g., cholinergic cell groups, doparminergic cell groups that are related on the 3 criteria but which we don't tend to consider nuclei because they don't occupy an easily defined territory. But all is open to debate.

nucleus

uberon

nucleus of neuraxis

UBERON:0000125

• nuclear complex of neuraxis