FOS and Anxiety: Our main and novel findings are as follows: (1) CSDS increased c-Fos expression in LSv GABAergic neurons; (2) although direct manipulation of LSv GABAergic neurons had little effect on anxiety- and despair-like behavioral performances, the activation of LSv GABAergic neurons during CSDS aggravated social anxiety in Gq animals; (3) the LSv sent GABAergic projections to the PVN; and (4) the activation of LSvGABA–PVN projections under basal conditions induced social anxiety, whereas activation of this pathway during CSDS alleviated social anxiety.