NFKB1 and Cognitive impairment: The transplantation of vancomycin-treated mouse feces, which contained a higher abundance of gut Proteobacteria than those of vancomycin-untreated mouse feces, also caused cognitive impairment and hippocampal inflammation compared to those in IFI feces-transplanted mice; it impaired the cognitive function and induced the hippocampal NF-κB-activated microglia cell population.