Functional Magnetic Resonance Imaging of Hippocampal Activation During Silent Mantra Meditation

Abstract

Objectives: The objective of the present study was to investigate whether moderately experienced meditators activate hippocampus and the prefrontal cortex during silent mantra meditation, as has been observed in earlier studies on subjects with several years of practice. Methods: Subjects with less than 2 years of meditation practice according to the Kundalini yoga or Acem tradition were examined by functional magnetic resonance imaging during silent mantra meditation, using an on-off block design. Whole-brain as well as region-of-interest analyses were performed. Results: The most significant activation was found in the bilateral hippocampus/parahippocampal formations. Other areas with significant activation were the bilateral middle cingulate cortex and the bilateral precentral cortex. No activation in the anterior cingulate cortex was found, and only small activation clusters were observed in the prefrontal cortex. Conclusions: In conclusion, the main finding in this study was the significant activation in the hippocampi, which also has been correlated with meditation in several previous studies on very experienced meditators. We propose that the hippocampus is activated already after moderate meditation practice and also during different modes of meditation, including relaxation. The role of hippocampal activity during meditation should be further clarified in future studies, especially by investigating whether the meditation-correlated hippocampal activity is related to memory consolidation.

The Meditative Mind: A Comprehensive Meta-Analysis of MRI Studies

“…These studies have reported increased activation in areas associated with attention, mind wandering, retrieval of episodic memories, and emotional processing during meditation [33]. Specifically, increased activation in the prefrontal cortex [34], parietal areas [35], middle cingulate cortex, and hippocampal and parahippocampal formations [36] has been reported.…”

Can Mindfulness Beat Alzheimer's Disease?

“…In this way, it has been consistently found that the hippocampus differs between meditators and non-meditators (Luders et al, 2013). Two different structural studies both detected significant larger grey matter concentration in the right hippocampus (Holzel et al, 2008), and greater right and left hippocampal volume (Luders et al, 2009;Luders et al, 2013).These findings were complemented by functional imaging studies using positron emission tomography (PET) scans or functional magnetic resonance imaging (fMRI), which show that, in both novice and expert meditators, there is increased brain activity in the left and right hippocampus during meditation or mindfulness exercises (Engström, Pihlsgård, Lundberg & Söderfeldt, 2010;Luders et al, 2013). Furthermore, investigations of pre-post changes in brain gray matter concentration and volume in participants of mindfulness-based interventions show promising results in other areas besides the hippocampus as well.…”

Zur Aussagekraft von Neuroimaging-Befunden im Strafprozess

“…z. b. 5,10,17]. Nicht zuletzt der Anspruch dieser Forschung, dass selbst solche abstrakten Denkinhalte systematisierbare, quantifizierbare und statistisch auswertbare entitäten darstellen, hat zu einer recht polemisch geführten Diskussion über die Validität und reliabilität von Neuroimaging-befunden geführt, wobei jedoch nicht vergessen werden sollte, dass selbst ausgesprochene Neuroimaging-skeptiker keinesfalls abstreiten würden, dass auch abstrakte Denkinhalte messbare Verän-derungen der Gehirnaktivität verursachen.…”