20 世纪70 年代，美国医生恩格尔对临床医学中占据主导位置的生物医学模式作出挑战，提出了“生物-心理-社会医学模式”，从此“心身疾病”的概念进入了人们的视线。在这个概念中，心理疾病是“因”，躯体症状是“果”，尽管心身疾病患者的躯体症状没有明确的生物学异常，但其临床症状是真实存在的，这类疾病被称为“功能性疾病”。到现在为止，人们还是认为，在心身疾病中，作为病因的心理障碍与躯体疾病一样，同样不存在明显的生物学异常。笔者认为心理障碍作为一种疾病，可能存在生物学异常，这种异常与人类大脑边缘系统，尤其是海马的变化有关。同时还进一步认为，边缘系统、海马的变化不仅与躯体的功能性疾病有关，同时与某些躯体器质性疾病也有关。笔者旨在说明，躯体功能性疾病与心理障碍之间并非一种因果关系，两者均可能是海马变化的后果，这些疾病的持续存在又可反过来促使海马病变加重，形成恶性循环。

In the 1970s，the American doctor George L.Engel challenged the dominant biomedical model in clinical medicine and put forward the "bio-psycho-social medical model"，from which the concept of "psychosomatic disease" caught people′s attention.In this concept，mental illness is the "cause" and physical symptoms are the "effect"，although the physical symptoms of patients with psychosomatic diseases do not have clear biological abnormalities，their clinical symptoms are real，such diseases are called"functional diseases".Until now，it is still believed that in psychosomatic diseases，psychological disorders as a cause of illness，like somatic diseases，do not have obvious biological abnormalities.The author believes that psychological disorders，as a kind of disease，may have biological abnormalities，which are related to the changes in the limbic system of the human brain，especially the hippocampus.At the same time，it is further believed that the changes in the limbic system and hippocampus are not only related to the functional diseases of the body，but also related to some organic diseases of the body.The purpose of this paper is to show that the relationship between physical functional diseases and psychological disorders is not a causal relationship，but both may be the result of changes in the hippocampus，and the persistence of these diseases may in turn promote the deterioration of hippocampal lesions，forming a vicious circle.