Using a neurophysiological assay (EEG) that is largely translatable between rodents and humans, we report that Grin2a and Akap11 mutants show several key EEG abnormalities that are also observed in patients with schizophrenia and bipolar disorder (summarized in Table S2), including increased resting gamma power and reduced evoked gamma oscillations, altered sleep spindle density, and abnormal MMN (in particular, altered P3a event-related potentials in the MMN paradigm). The gene discussed is GRIN2A; the disease is bipolar disorder.