Source Localization During Meditation: Traces of Long-Term Practice of Meditation
Presenter: BK Shrikant
Authors(s): BK Shrikant, Sushil Chandra
Organization: Institute of Nuclear medicine and Allied Science, Biomedical Engineering
Prominent functional and anatomical changes due to exposure of meditation practice have been observed in the past few decades. In addition, methods adopted in various type of meditation incur changes in cognitive processing. Such changes can be assessed through physiological devices, for instance, EEG, which is a promising technique for temporal assessment in real time. It displays transient changes in different frequency bands due to meditation practice. Raj yoga meditation is taught by Brahmakumaris and has been followed by more than one million followers across the globe. Rajayoga Meditation is a practice of self-regulation of mind, intellect, and subconsciousness by engaging in a specific attentional set. Attention is a state of mind that links alertness, orientation, and executive control. Meditation primarily enhances the efficiency of brain regions, which govern attention. This study examines the effect on the attentional network of long-term raj yoga meditators using a single attention network task and dynamics of 64 channel high density EEG. Here we investigated the brain activations during meditation for long-term meditators and resting state for non-meditators using sLORETA. EEG was recorded for ten volunteers (five meditators and five control subjects). Control subjects had no prior experience of any kind of meditation practice. Higher activations were observed on the parietal region for long-term meditators. Parietal activation is related to alerting and orientation. Anterior cingulate and Angular gyrus were among other activated regions. Brain activation pattern indicates higher self-awareness and alertness in long-term Rajayoga meditators. The behavioural study shows higher accuracy in the attention network task in long-term meditators when compared to control subjects. Overall findings suggested a positive impact of meditation on frontal and parietal areas of the brain, involved in processes of regulation of selective attention and sustaining it. Limitation of this study was the small sample size.