Therefore, we speculate that a model of a neuronal excitatory/inhibitory imbalance might explain the plethora of neuropsychiatric symptoms that can be observed in the course of NMDR encephalitis: Initial hyperglutamatergic states can be interpreted as an indicator of cortical over-excitation, whereas hypoglutamatergic states in the further course (after months) of the disease might be a sequel of over-inhibition of cortical brain areas, possibly triggered by the preceding over-excitation.
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