Saini Manorma, Gurjar Ankit, Muthukrishnan Suriya Prakash, Kaur Simran, Sharma Ratna, Tayade Prashant T
Department of Physiology, All India Institute of Medical Sciences, Kalyani, West Bengal, India.
Department of Physiology, All India Institute of Medical Sciences, New Delhi, India.
Ann Neurosci. 2024 Jul;31(3):176-185. doi: 10.1177/09727531231183219. Epub 2023 Aug 17.
Meditation using the "OM" mantra is the most widely used practice in India. Though reports have been published about the relaxation effect during both verbal "OM" chanting and listening to "OM" chanting, there is a paucity of literature concerning the cortical areas activated/deactivated after verbal "OM" chanting and listening to "OM" chanting using quantitative electro-encephalography (qEEG).
The objective of this study was to compare the effects of verbal "OM" chanting and listening to "OM" chanting on cortical sources as compared to baseline, as assessed by qEEG.
Twenty adult male subjects with a mean age of 27.5 ± 7.5 years and no past or present history of psychiatric, neurological, or auditory disorders or previous exposure to yoga and meditation were recruited from the undergraduate and postgraduate student population of AIIMS, New Delhi. Subjects were given a paradigm designed using E-prime for both verbal and listening to "OM" chanting of 5 min each and a 5-min relaxation period in between the tasks. Electroencephalography recording was done using a 128-channel geodesic sensor net with band-pass filtered at 1-70 Hz, and 20-sec data of eyes-closed condition, post-verbal "OM", and post-listening to "OM" chanting were segmented and pre-processed. Further, source analysis was performed on the data using standardized low-resolution electromagnetic tomography.
The pre (baseline) versus post-verbal "OM" ( < .05) and post-listening to "OM" ( < .05) chanting showed significant differences in similar cortical areas in both verbal "OM" and listening to "OM" chanting except the three areas, that is, the orbital gyrus, the rectal gyrus, and the sub-callosal gyrus, which were additionally activated post-listening to "OM" chanting. Both verbal and listening to "OM" chanting induced activation of similar cortical areas, which were classified as the nodes/hubs of specific resting-state networks (RSNs) such as the attentional network, frontoparietal control network, and default mode network.
The study results suggest that "OM" chanting could facilitate flexible switching between various RSNs to induce a relaxed state and could improve attention simultaneously.Both verbal and listening to "OM" chanting induced common activated areas that are classified into frontoparietal, dorsal attention, and default mode network areas. And it is hypothesized that flexible switching between these RSNs could induce a relaxed state and improve attention simultaneously with the possible role of the frontoparietal network.
使用“唵”字真言冥想是印度最广泛使用的修行方式。尽管已有关于出声念诵“唵”字真言和聆听“唵”字真言时放松效果的报道，但关于通过定量脑电图（qEEG）测量出声念诵“唵”字真言和聆听“唵”字真言后大脑皮质区域激活/失活情况的文献却很匮乏。
本研究的目的是通过qEEG评估，比较出声念诵“唵”字真言和聆听“唵”字真言对大脑皮质源的影响与基线相比的差异。
从新德里全印医学科学研究所的本科生和研究生群体中招募了20名成年男性受试者，平均年龄为27.5±7.5岁，既往及目前均无精神、神经或听觉疾病史，也未曾接触过瑜伽和冥想。受试者被给予一个使用E-prime设计的范式，分别进行出声念诵“唵”字真言和聆听“唵”字真言，各持续5分钟，两项任务之间有5分钟的放松期。使用128通道测地线传感器网络进行脑电图记录，带通滤波范围为1 - 70Hz，对闭眼状态、出声念诵“唵”字真言后以及聆听“唵”字真言后的20秒数据进行分段和预处理。此外，使用标准化低分辨率电磁断层扫描对数据进行源分析。
出声念诵“唵”字真言后（p <.05）和聆听“唵”字真言后（p <.05）与基线相比，在出声念诵“唵”字真言和聆听“唵”字真言时，相似的大脑皮质区域均显示出显著差异，但有三个区域除外，即眶回、直肠回和胼胝体下回，这三个区域在聆听“唵”字真言后额外被激活。出声念诵“唵”字真言和聆听“唵”字真言均诱导了相似大脑皮质区域的激活，这些区域被归类为特定静息态网络（RSN）的节点/枢纽，如注意网络、额顶叶控制网络和默认模式网络。
研究结果表明，念诵“唵”字真言可促进不同RSN之间的灵活切换以诱导放松状态，并可同时提高注意力。出声念诵“唵”字真言和聆听“唵”字真言均诱导了共同的激活区域，这些区域被归类为额顶叶、背侧注意和默认模式网络区域。据推测，这些RSN之间的灵活切换可能诱导放松状态并同时提高注意力，额叶顶叶网络可能起到了作用。
