TPH2 and Anxiety: Interestingly, despite similar latencies to feed in the NSFT (Figure 5g), Tph2−/− mice spent significantly more time feeding in the center of the novel, brightly lit arena than their Tph2+/− and Tph2+/+ littermates (total feeding time: F(2,28)=3.68, P=0.038, Figure 5h; mean feeding time per event: F(2,28)=5.33, P=0.011, Figure 5h), thereby arguing for reduced anxiety-like behavior in the presence of rewarding stimuli such as food pellets.