School of Sport and Exercise Sciences, University of Birmingham, Birmingham, UK.
Psychophysiology. 2013 Mar;50(3):219-29. doi: 10.1111/psyp.12017. Epub 2013 Jan 25.
The present study compared neural activity in participants with blunted (N = 9) or exaggerated (N = 8) cardiac stress reactions. Neural activity was recorded with fMRI while participants performed a validated stress task and control task. Exaggerated reactors exhibited significant increases in heart rate from control to stress task, whereas blunted reactors had no change in heart rate. Blunted reactors also had reduced activation in the anterior midcingulate cortex and insula compared to exaggerated reactors during the stress condition, and a greater deactivation in the amygdala and posterior cingulate. The biological differences between groups in response to the stress task could not be explained by subjective measures of engagement, stressfulness, or difficulty. This study supports the notion that blunted peripheral physiological stress reactivity may be a marker of a corresponding under-recruitment of brain systems during behavioral states requiring motivated action.
本研究比较了心脏应激反应迟钝（N=9）或过度（N=8）的参与者的神经活动。参与者在进行经过验证的应激任务和对照任务时，使用 fMRI 记录神经活动。过度反应者在从对照任务到应激任务时心率显著增加，而反应迟钝者心率没有变化。与过度反应者相比，反应迟钝者在应激状态下中前扣带皮层和脑岛的激活减少，杏仁核和后扣带的去激活增加。这些组间在应激任务反应中的生物学差异不能用主观的参与度、压力感或难度来解释。这项研究支持这样一种观点，即外周生理应激反应迟钝可能是在需要动机行为的行为状态下大脑系统相应招募不足的标志。
