In addition to this “social environmental enrichment”, enrichment in housing conditions (running wheel, toys, tunnels, ladders, etc.)also ameliorates impaired anxiety-like behavior (91, 209, 264), visual recognition memory (209, 264), spatial learning and memory (91, 265), and fear memory (91), potentially by acting on the hippocampal BDNF/TrkB-PLCγ1-CaMKII pathway (91, 209, 264, 265), as observed in Fmr1-KO mice (91), VPA-exposed mice (209), Ube3a-KO mice (264), and MIA rats (265). Here, NTRK2 is linked to Anxiety.