Several studies investigating a functional polymorphism of the AEA-degrading enzyme FAAH (C385C- > A), which results in reduced FAAH activity and therefore higher AEA concentrations, have repeatedly shown that carriers with lower FAAH activity exhibit better stress or fear-related behavior [82], e.g., reduced subjective anxiety responses to a stress task [83], improved fear extinction [56] and more successful extinction recall [84]. Here, FAAH is linked to Anxiety.