LHB and major depressive disorder: Given the pivotal role of the LHb in regulation of midbrain nuclei activity and therefore in reward-related behaviors, it was suggested that modulation of this region by DBS might be an effective therapeutic tool for psychiatric disorders, including major depression (Sartorius and Henn, 2007; Hauptman et al., 2008), and drug addiction (Luigjes et al., 2012).