Cognitive impairment has been observed in patients with various psychiatric disorders, including schizophrenia, major depressive disorder (MDD), and bipolar disorder (BD). Although modern therapeutic drugs can improve certain symptoms (i.e., psychosis, depression) in these patients, these drugs have not been found to improve cognitive impairment. The N-methyl-D-aspartate receptor antagonist (R,S)-ketamine has attracted attention as a rapidly acting antidepressant. In addition to its robust antidepressant effects, (R,S)-ketamine has been suggested to improve cognitive impairment in patients with MDD and BD, despite causing cognitive impairment in healthy control subjects. (R,S)-ketamine is a racemic mixture of equal amounts of (R)-ketamine (or arketamine) and (S)-ketamine (or esketamine). Arketamine has been found to have more potent antidepressant-like actions than esketamine in rodents. Interestingly, arketamine, but not esketamine, has been suggested to improve phencyclidine-induced cognitive deficits in mice. Furthermore, arketamine has been suggested to ameliorate cognitive deficits in rodent offspring after maternal immune activation. In the current article, it is proposed that arketamine has therapeutic potential for treating cognitive impairment in patients with psychiatric disorders. Additionally, the potential role of the gut–microbiome–brain axis in cognitive impairment in psychiatric disorders is discussed.

在患有各种精神疾病的患者中观察到认知障碍，包括精神分裂症、重度抑郁症（MDD）和双相情感障碍（BD）。尽管现代治疗药物可以改善这些患者的某些症状（即精神病、抑郁症），但尚未发现这些药物可以改善认知障碍。N-甲基-D-天冬氨酸受体拮抗剂（R,S ）-氯胺酮作为一种快速作用的抗抑郁药引起了人们的关注。除了其强大的抗抑郁作用外，( R,S )-氯胺酮还被认为可以改善 MDD 和 BD 患者的认知障碍，尽管它会导致健康对照受试者的认知障碍。( R , S )-氯胺酮是等量的( R )-氯胺酮(或芳氯胺酮)和( S )-氯胺酮(或艾氯胺酮)的外消旋混合物。研究发现，在啮齿类动物中，阿氯胺酮比艾氯胺酮具有更有效的抗抑郁作用。有趣的是，阿氯胺酮（而不是艾氯胺酮）被认为可以改善苯环己哌啶诱导的小鼠认知缺陷。此外，阿氯胺酮被认为可以改善啮齿动物后代在母体免疫激活后的认知缺陷。在本文中，提出阿氯胺酮具有治疗精神疾病患者认知障碍的潜力。此外，还讨论了肠道-微生物组-大脑轴在精神疾病认知障碍中的潜在作用。