Johnson explains how scientists have found that patients with depression have less of a particular type of bacteria called bacteroides, which is known to produce an important chemical called GABA (gamma-aminobutyric acid).

约翰逊解释了科学家如何发现抑郁症患者体内一种叫做类杆菌的特殊细菌较少，这种细菌会产生一种叫做 GABA（γ-氨基丁酸）的重要化学物质。