Editing Basal ganglia (section)

==Other animals==
{{See also|Primate basal ganglia system}}
The basal ganglia form one of the basic components of the [[telencephalon|forebrain]], and can be recognized in all species of vertebrates.<ref name="Parent">{{cite book|title=Comparative Neurobiology of the Basal Ganglia | vauthors = Parent A |publisher=Wiley |year=1986 |isbn=978-0-471-80348-5}}{{Page needed|date=December 2010}}</ref> Even in the lamprey (generally considered one of the most primitive of vertebrates), striatal, pallidal, and nigral elements can be identified on the basis of anatomy and histochemistry.<ref name=Grillner1998>{{cite journal | vauthors = Grillner S, El Manira A, Lansner A, Parker D, Tegnér J, Wallén P | title = Intrinsic function of a neuronal network – a vertebrate central pattern generator | journal = Brain Research. Brain Research Reviews | volume = 26 | issue = 2–3 | pages = 184–197 | date = May 1998 | pmid = 9651523 | doi = 10.1016/S0165-0173(98)00002-2 | s2cid = 42554138 }}</ref>

The names given to the various nuclei of the basal ganglia are different in different species. In [[cat]]s and [[rodent]]s the internal globus pallidus is known as the ''entopeduncular nucleus''.<ref>{{cite journal | vauthors = Redgrave P | title = Basal ganglia | journal = Scholarpedia | date = June 2007 |  volume = 2 | issue = 6 | page = 1825 | doi = 10.4249/scholarpedia.1825 | doi-access = free }}</ref> In [[bird]]s the striatum is called the ''paleostriatum augmentatum'' and the external globus pallidus is called the ''paleostriatum primitivum''.

A clear emergent issue in comparative anatomy of the basal ganglia is the development of this system through phylogeny as a convergent cortically re-entrant loop in conjunction with the development and expansion of the cortical mantle. There is controversy, however, regarding the extent to which convergent selective processing occurs versus segregated parallel processing within re-entrant closed loops of the basal ganglia. Regardless, the transformation of the basal ganglia into a cortically re-entrant system in mammalian evolution occurs through a re-direction of pallidal (or "paleostriatum primitivum") output from midbrain targets such as the superior colliculus, as occurs in [[sauropsid]] brain, to specific regions of the ventral thalamus and from there back to specified regions of the cerebral cortex that form a subset of those cortical regions projecting into the striatum. The abrupt rostral re-direction of the pathway from the internal segment of the globus pallidus into the ventral thalamus—via the path of the [[ansa lenticularis]]—could be viewed as a footprint of this evolutionary transformation of basal ganglia outflow and targeted influence.