GRM5 and Alzheimer disease: Though previous studies have demonstrated that a broad conceptual role of mGluR5 antagonism is the restoration of memory function in TG mouse models of Alzheimer’s disease (e.g. Hamilton et al., 2016), our study provides a framework for these effects: the aberrant activation of mGluR5 impairing postsynaptic mAChR function, where through blocking mGluR5, postsynaptic mAChR function and object recognition memory in Alzheimer’s disease models can be restored.