Editing Subthalamic nucleus (section)

===Efferent targets===
The axons of subthalamic nucleus neurons leave the nucleus dorsally. The efferent axons are glutamatergic (excitatory). Except for the connection to the striatum (17.3% in macaques), most of the subthalamic principal neurons are multitargets and directed to the other elements of the core of the basal ganglia.<ref name="pmid418083">{{cite journal | vauthors = Nauta HJ, Cole M | title = Efferent projections of the subthalamic nucleus: an autoradiographic study in monkey and cat | journal = The Journal of Comparative Neurology | volume = 180 | issue = 1 | pages = 1–16 | date = July 1978 | pmid = 418083 | doi = 10.1002/cne.901800102 | s2cid = 43046462 }}</ref> Some send axons to the substantia nigra medially and to the medial and lateral nuclei of the pallidum laterally (3-target, 21.3%). Some are 2-target with the lateral pallidum and the substantia nigra (2.7%) or the lateral pallidum and the medial (48%). Less are single target for the lateral pallidum. In the pallidum, subthalamic terminals end in bands parallel to the pallidal border.<ref name="pmid418083"/><ref name=Smith1990>{{cite journal | vauthors = Smith Y, Hazrati LN, Parent A | title = Efferent projections of the subthalamic nucleus in the squirrel monkey as studied by the PHA-L anterograde tracing method | journal = The Journal of Comparative Neurology | volume = 294 | issue = 2 | pages = 306–323 | date = April 1990 | pmid = 2332533 | doi = 10.1002/cne.902940213 | s2cid = 9667393 }}</ref> When all axons reaching this target are added, the main efference of the subthalamic nucleus is, in 82.7% of the cases, clearly the [[internal globus pallidus]] (GPi).

Some researchers have reported internal [[axon]] collaterals.<ref>{{cite journal | vauthors = Kita H, Chang HT, Kitai ST | title = The morphology of intracellularly labeled rat subthalamic neurons: a light microscopic analysis | journal = The Journal of Comparative Neurology | volume = 215 | issue = 3 | pages = 245–257 | date = April 1983 | pmid = 6304154 | doi = 10.1002/cne.902150302 | s2cid = 32152785 }}</ref> However, there is little functional evidence for this.