Kleinknecht R A, Lenz J, Ford G, DeBerard S
Department of Psychology, Western Washington University, Bellingham 98225.
Behav Res Ther. 1990;28(4):289-95. doi: 10.1016/0005-7967(90)90080-3.
This study investigated by interview, the initial syncopal episode of 103 blood/injury-related vasovagal fainters in order to examine two competing hypotheses concerning their origins. Graham (Circulation, 23, 901-906, 1961) postulated that the faint resulted when sympathetic nervous system (SNS) activity ceased on termination of a threat, leaving parasympathetic nervous system (PNS) activation unopposed. Engel [Fainting (2nd edn), 1962; Annals of Internal Medicine, 89, 901-906, 1978] proposed that when in the face of threat with SNS activation, escape is blocked, the PNS becomes activated as the conservation-withdrawal response, leading to syncope. We found cases clearly conforming to each of these formulations as well as some with characteristics of both, and some who fainted in response to blood or injury but with no perception of threat. The Graham and Engel types did not differ in terms of fear or avoidance of blood, injury, or medically-related situations nor did they differ in the frequency with which their parents reported blood/injury-related syncopal episodes. It is proposed that both may be activated by a common psychological mechanism involving cessation of a defensive posture. In contrast, the non-threat fainters showed significantly less medically-related avoidance and had a greater percentage (94%) of parents with positive faint histories.
本研究通过访谈对103例与血液/损伤相关的血管迷走性晕厥患者的首次晕厥发作进行了调查，以检验关于其病因的两种相互竞争的假说。格雷厄姆（《循环》，第23卷，901 - 906页，1961年）推测，当威胁终止时交感神经系统（SNS）活动停止，副交感神经系统（PNS）的激活未受到对抗，从而导致晕厥。恩格尔[《晕厥》（第2版），1962年；《内科学年鉴》，第89卷，901 - 906页，1978年]提出，面对伴有SNS激活的威胁时，若逃跑受阻，PNS作为保存 - 退缩反应而被激活，进而导致晕厥。我们发现了明确符合这两种表述的病例，以及一些兼具两者特征的病例，还有一些因血液或损伤而晕厥但并无威胁感的病例。格雷厄姆型和恩格尔型在对血液、损伤或医疗相关情况的恐惧或回避方面并无差异，其父母报告的与血液/损伤相关的晕厥发作频率也无差异。有人提出，两者可能都由一种涉及防御姿势停止的共同心理机制所激活。相比之下，无威胁感晕厥者表现出明显较少的与医疗相关的回避行为，且其父母有阳性晕厥病史的比例更高（94%）。
