单纯逆行性遗忘综合征（IRAS）是一种少见的记忆障碍,主要表现为逆行性记忆严重丧失,同时顺行性记忆基本保留。脑外伤、炎症、缺氧、血管病变、精神因素等多种原因均可导致IRAS。其发病机制不详,病理检查发现患者病变的部位主要集中在额颞部,间脑、枕叶损伤亦可产生IRAS。预后依病因不同而不同。 Simple retrograde amnestic syndrome (IRAS) is a rare memory disorder, mainly manifested as a serious loss of retrograde memory, while the basic memory of antegrade memory. Brain trauma, inflammation, hypoxia, vascular disease, mental factors and other reasons can lead to IRAS. The pathogenesis is unknown, the pathological examination found that patients with lesions mainly in the frontotemporal parts of the brain, occipital lobe injury can also produce IRAS. The prognosis varies depending on the cause.