PVALB and schizophrenia: At the microcircuit level, these models suggest that NMDAR hypofunction in schizophrenia is considered to mainly affect parvalbumin-positive GABAergic interneurons leading to a disinhibition of glutamatergic pyramidal cells and consequently an imbalance of neural excitation and inhibition (E/I-imbalance, see Fig. 1d) [2, 5].