Department of Neurology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany.
Neuroimage. 2010 Apr 1;50(2):847-54. doi: 10.1016/j.neuroimage.2009.12.004. Epub 2009 Dec 11.
Activation of the sympathetic nervous system (SNS) is essential in adapting to environmental stressors and in maintaining homeostasis. This reaction can also turn into maladaptation, associated with a wide spectrum of stress-related diseases. Up to now, the cortical mechanisms of sympathetic activation in acute mental stress have not been sufficiently characterized. We therefore investigated cerebral activation applying functional magnetic resonance imaging (fMRI) during performance of a mental stress task with graded levels of difficulty, i.e. four versions of a Stroop task (Colour Word Interference Test, CWT) in healthy subjects. To analyze stress-associated sympathetic activation, skin conductance and heart rate were continuously recorded. The results show that sympathetic activation through mental stress is associated with distinct cerebral regions being immediately involved in task performance (visual, motor, and premotor areas). Other activated regions (right insula, dorsolateral superior frontal gyrus, cerebellar regions) are unrelated to task performance. These latter regions have previously been considered to be involved in mediating different stress responses. The results might furthermore serve as a basis for future investigations of the connection between these cortical regions in the generation of stress-related diseases.
激活交感神经系统（SNS）对于适应环境应激源和维持体内平衡至关重要。这种反应也可能变成适应不良，与广泛的应激相关疾病有关。到目前为止，急性心理应激中交感神经激活的皮质机制尚未得到充分描述。因此，我们在健康受试者中进行了一项具有不同难度级别的心理应激任务（即四种 Stroop 任务版本），应用功能磁共振成像（fMRI）研究了大脑的激活情况。为了分析与应激相关的交感神经激活，我们连续记录皮肤电导和心率。结果表明，通过心理应激产生的交感神经激活与大脑中立即参与任务执行的特定区域（视觉、运动和运动前区）有关。其他激活的区域（右侧脑岛、背外侧额上回、小脑区域）与任务执行无关。这些区域之前被认为与调节不同的应激反应有关。这些结果可能为未来研究这些皮质区域在应激相关疾病产生中的联系提供基础。
