GRIN2B and schizophrenia: The glutamatergic system, as well, appears to be implicated in the neurocircuits relevant for OCS as reported by both cerebrospinal fluid and MRS studies that reveal alterations in glutamatergic metabolites [67,136] and genetic findings concerning GRIN2B and DLGAP1 [19,137], which are also strongly associated with schizophrenia [138,139].