The posterior subthalamic area (PSA) includes the zona incerta (ZI) and the prelemniscal radiation (RaprL), which itself consists of the cerebellothalamic fascicle (fct) (or dentato-rubro-thalamic tract [DRTT]) and pallidothalamic fibers, and was targeted for lesioning as early as 1960 by Wertheimer et al. 1).
1)
Wertheimer P, Lapras C, Levy A: [Trials in thalamic surgery.] Neurochirurgie 6:105–112, 1960