GRM5 and Cognitive impairment: Recent therapeutic strategies for the treatment of schizophrenia focus on the pharmacological interaction between mGluR5 and NMDA receptors (NMDARs; Homayoun et al., 2004; Stefani and Moghaddam, 2010), as it is well established that mGluR5 synergistically facilitates NMDAR function to alleviate the cognitive deficits associated with schizophrenia (Awad et al., 2000; Attucci et al., 2001; Pisani et al., 2001; Rosenbrock et al., 2010).