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Inappropriate responses to prior experiences and deficits in adaptive learning and behavioral flexibility can be extremely detrimental, resulting in disorders such as post-traumatic stress disorder. Therefore, describing the mechanisms that facilitate fear extinction in animal models is important for understanding human neuropsychiatric disorders. Xu et al. (2013) (LearnMem 20: 438–445) demonstrate that a positive allosteric modulator (PAM) of a metabotropic glutamate receptor 5 (mGluR5) enhances extinction learning in mice. The cover art depicts the structural topology of mGluR5 and the molecular structure of the PAM. Data from the article by Xu and colleagues are depicted to show that freezing is reduced in the group that had previously been administered the drug during a retrieval trial. These results suggest that mGluR5 may be a viable target for disorders involving maladaptive learning.