GPR83 and Anxiety: In the open field assay, there was no difference in the amount of time GPR83 KO mice spent in the center of the open field; however, there was a significant increase in the frequency that they entered the center region, also an indication of lower anxiety-like behavior (unpaired t-test, center time, t = 1.332, df = 51; frequency, t = 2.315, df = 53; Figures 1E,F).