FGF2 and Anxiety: There are many different interactions of FGF ligands and FGFRs, such that specific roles for FGF ligands—such as FGF17 in social behavior, FGF22 in anhedonia-like behavior, or FGF2 or FGF8 in anxiety-like behavior—leaves undetermined what receptors and cells mediate these effects [10, 14, 17, 18].