IL6 and schizophrenia: IL-6 affects neuronal transmission and survival in the prefrontal cortex and hippocampus and causes the reduction of gray-matter thickness, and thus cognitive impairment, in patients with schizophrenia and other mental disorders26,27,34–41 Several therapeutic agents, including antipsychotics, reduce the IL-6 level and thus alleviate this effect25,42–47.