Wang Jiongjiong, Rao Hengyi, Wetmore Gabriel S, Furlan Patricia M, Korczykowski Marc, Dinges David F, Detre John A
Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
Proc Natl Acad Sci U S A. 2005 Dec 6;102(49):17804-9. doi: 10.1073/pnas.0503082102. Epub 2005 Nov 23.
Despite the prevalence of stress in everyday life and its impact on happiness, health, and cognition, little is known about the neural substrate of the experience of everyday stress in humans. We use a quantitative and noninvasive neuroimaging technique, arterial spin-labeling perfusion MRI, to measure cerebral blood flow (CBF) changes associated with mild to moderate stress induced by a mental arithmetic task with performance monitoring. Elicitation of stress was verified by self-report of stress and emotional state and measures of heart rate and salivary-cortisol level. The change in CBF induced by the stress task was positively correlated with subjective stress rating in the ventral right prefrontal cortex (RPFC) and left insula/putamen area. The ventral RPFC along with right insula/putamen and anterior cingulate showed sustained activation after task completion in subjects reporting a high stress level during arithmetic tasks. Additionally, variations of baseline CBF in the ventral RPFC and right orbitofrontal cortex were found to correlate with changes in salivary-cortisol level and heart rate caused by undergoing stress tasks. We further demonstrated that the observed right prefrontal activation could not be attributed to increased cognitive demand accompanying stress tasks and extended beyond neural pathways associated with negative emotions. Our results provide neuroimaging evidence that psychological stress induces negative emotion and vigilance and that the ventral RPFC plays a key role in the central stress response.
尽管日常生活中压力普遍存在，且对幸福感、健康和认知产生影响，但对于人类日常压力体验的神经基础却知之甚少。我们使用一种定量且无创的神经成像技术——动脉自旋标记灌注磁共振成像（MRI），来测量与由带有表现监测的心算任务诱发的轻度至中度压力相关的脑血流量（CBF）变化。通过压力和情绪状态的自我报告以及心率和唾液皮质醇水平的测量来验证压力的诱发情况。压力任务诱发的CBF变化与腹侧右前额叶皮层（RPFC）和左侧岛叶/壳核区域的主观压力评分呈正相关。在算术任务期间报告高压力水平的受试者中，腹侧RPFC连同右侧岛叶/壳核和前扣带回在任务完成后表现出持续激活。此外，发现腹侧RPFC和右侧眶额皮层的基线CBF变化与经历压力任务引起的唾液皮质醇水平和心率变化相关。我们进一步证明，观察到的右侧前额叶激活不能归因于压力任务伴随的认知需求增加，且超出了与负面情绪相关的神经通路。我们的结果提供了神经成像证据，表明心理压力会诱发负面情绪和警觉，且腹侧RPFC在中枢压力反应中起关键作用。
