Kubota Y, Sato W, Toichi M, Murai T, Okada T, Hayashi A, Sengoku A
Department of Neuropsychiatry, Faculty of Medicine, Kyoto University, Shogoin-Kawaharacho, 606-8507, Kyoto, Japan.
Brain Res Cogn Brain Res. 2001 Apr;11(2):281-7. doi: 10.1016/s0926-6410(00)00086-0.
Frontal midline theta rhythm (Fm theta), recognized as distinct theta activity on EEG in the frontal midline area, reflects mental concentration as well as meditative state or relief from anxiety. Attentional network in anterior frontal lobes including anterior cingulate cortex is suspected to be the generator of this activity, and the regulative function of the frontal neural network over autonomic nervous system (ANS) during cognitive process is suggested. However no studies have examined peripheral autonomic activities during Fm theta induction, and interaction of central and peripheral mechanism associated with Fm theta remains unclear. In the present study, a standard procedure of Zen meditation requiring sustained attention and breath control was employed as the task to provoke Fm theta, and simultaneous EEG and ECG recordings were performed. For the subjects in which Fm theta activities were provoked (six men, six women, 48% of the total subjects), peripheral autonomic activities were evaluated during the appearance of Fm theta as well as during control periods. Successive inter-beat intervals were measured from the ECG, and a recently developed method of analysis by Toichi et al. (J. Auton. Nerv. Syst. 62 (1997) 79-84) based on heart rate variability was used to assess cardiac sympathetic and parasympathetic functions separately. Both sympathetic and parasympathetic indices were increased during the appearance of Fm theta compared with control periods. Theta band activities in the frontal area were correlated negatively with sympathetic activation. The results suggest a close relationship between cardiac autonomic function and activity of medial frontal neural circuitry.
额中线θ节律（Fm theta），被认为是额中线区域脑电图上独特的θ活动，反映了精神集中以及冥想状态或焦虑缓解。包括前扣带回皮质在内的前额叶前部的注意力网络被怀疑是这种活动的产生源，并且有人提出在认知过程中额叶神经网络对自主神经系统（ANS）的调节功能。然而，尚无研究考察Fm theta诱发期间的外周自主活动，并且与Fm theta相关的中枢和外周机制的相互作用仍不清楚。在本研究中，采用需要持续注意力和呼吸控制的禅宗冥想标准程序作为诱发Fm theta的任务，并同时进行脑电图和心电图记录。对于诱发了Fm theta活动的受试者（6名男性，6名女性，占总受试者的48%），在Fm theta出现期间以及对照期评估外周自主活动。从心电图测量连续的心搏间期，并使用Toichi等人（《自主神经系统杂志》62（1997）79 - 84）最近开发的基于心率变异性的分析方法分别评估心脏交感神经和副交感神经功能。与对照期相比，在Fm theta出现期间交感神经和副交感神经指标均增加。额叶区域的θ波段活动与交感神经激活呈负相关。结果表明心脏自主功能与内侧额叶神经回路活动之间存在密切关系。
