TAC1 and depressive disorder: In light of the higher expression of tachykinin 2 in the posterior and medial PVT, and the known ability of posterior PVT stimulation to affect anxiety-like behavior (Barson et al., 2020) and ethanol drinking (Pandey et al., 2019), as well as the involvement of the PVT in depression-like behavior (Kasahara et al., 2016; Kato et al., 2019), we hypothesize that tachykinin 2/neurokinin B in cells in the PVT could promote a positive affective state and reduce the intake of drugs of abuse.