Travis F, Wallace R K
Maharishi University of Management, Fairfield, Iowa 52557, USA.
Conscious Cogn. 1999 Sep;8(3):302-18. doi: 10.1006/ccog.1999.0403.
In this single-blind within-subject study, autonomic and EEG variables were compared during 10-min, order-balanced eyes-closed rest and Transcendental Meditation (TM) sessions. TM sessions were distinguished by (1) lower breath rates, (2) lower skin conductance levels, (3) higher respiratory sinus arrhythmia levels, and (4) higher alpha anterior-posterior and frontal EEG coherence. Alpha power was not significantly different between conditions. These results were seen in the first minute and were maintained throughout the 10-min sessions. TM practice appears to (1) lead to a state fundamentally different than eyes-closed rest; (2) result in a cascade of events in the central and autonomic nervous systems, leading to a rapid change in state (within a minute) that was maintained throughout the TM session; and (3) be best distinguished from other conditions through autonomic and EEG alpha coherence patterns rather than alpha power. Two neural networks that may mediate these effects are suggested. The rapid shift in physiological functioning within the first minute might be mediated by a "neural switch" in prefrontal areas inhibiting activity in specific and nonspecific thalamocortical circuits. The resulting "restfully alert" state might be sustained by a basal ganglia-corticothalamic threshold regulation mechanism automatically maintaining lower levels of cortical excitability.
在这项单盲受试者内研究中，对自主神经和脑电图变量在10分钟、顺序平衡的闭眼休息和超觉静坐（TM）期间进行了比较。TM期间的特点为：（1）呼吸频率较低；（2）皮肤电导水平较低；（3）呼吸性窦性心律失常水平较高；（4）脑电图α前后和额叶连贯性较高。不同条件下的α波功率无显著差异。这些结果在第一分钟就已出现，并在整个10分钟期间保持。TM练习似乎（1）导致一种与闭眼休息根本不同的状态；（2）引发中枢和自主神经系统中的一系列事件，导致状态在一分钟内迅速改变，并在整个TM期间持续；（3）通过自主神经和脑电图α连贯性模式而非α波功率与其他条件进行最佳区分。文中提出了两个可能介导这些效应的神经网络。第一分钟内生理功能的快速转变可能由前额叶区域中的“神经开关”介导，该开关抑制特定和非特定丘脑皮质回路中的活动。由此产生的“宁静警觉”状态可能由基底神经节 - 皮质丘脑阈值调节机制维持，该机制自动维持较低水平的皮质兴奋性。
