Human brain mapping
May 1, 2024
Saampras Ganesan, Winson F Z Yang, Avijit Chowdhury et al.
23 citations
In an adept practitioner performing jhana meditation over 5 days inside a 7 Tesla MRI scanner (27 runs), the thalamus and several cortical networks—somatomotor, limbic, default-mode, control, and temporo-parietal—showed good within-subject reliability across all jhanas. When fMRI measurements were adjusted for variability in self-reported phenomenology, other networks such as attention and salience showed noticeable increases in reliability. The findings provide a preliminary template of reliable brain areas likely underpinning core neurocognitive elements of jhana meditation and highlight the value of neurophenomenological designs for characterizing neuronal variability in advanced meditative states.
Brain research bulletin
October 15, 2023
Saampras Ganesan, Bradford A Moffat, Nicholas T Van Dam et al.
13 citations
Using 7 Tesla functional MRI, a pilot study scanned 10 beginner meditators during focused attention meditation (attending to breathing) and non-focused rest. After adjusting for physiological differences, meditation reduced activity in default-mode network hubs (antero-medial prefrontal and posterior cingulate cortices, precuneus) and visual and thalamic regions compared to rest. These reductions survived stringent corrections for physiological fluctuations. State mindfulness scores rose significantly after the session and remained elevated at a 2-week follow-up. The findings support evidence that focused attention meditation dampens default-mode activity tied to self-referential processing and demonstrate the feasibility of ultra-high field fMRI for meditation research.
Biological psychiatry. Cognitive neuroscience and neuroimaging
April 1, 2025
Saampras Ganesan, Fernando A Barrios, Ishaan Batta et al.
6 citations
Meditation practices, which have shown therapeutic benefits for conditions like depression, pain, addiction, and anxiety, have been studied with neuroimaging over the past decade. However, existing neuroscientific models are based on small, heterogeneous datasets, limiting generalizability and replicability. The ENIGMA-Meditation consortium is the first worldwide collaborative effort to conduct systematic meta- and mega-analyses of globally distributed neuroimaging data using standardized methods. This framework aims to improve statistical power and address multidomain heterogeneity in meditation practice types, experience, and experimental design. The consortium will generate rigorous neuroscientific insights into the mechanisms underlying meditation's therapeutic effects on psychological and cognitive attributes.
bioRxiv (Cold Spring Harbor Laboratory)
October 26, 2024
Saampras Ganesan, Nicholas T. van Dam, Sunjeev K. Kamboj et al.
3 citations
preprint
Personalized high-precision neurofeedback (NF) can help novice meditators better disengage from mental activity during meditation, improving emotional well-being and mindful awareness. In a single-blind, controlled study, 40 novices received two days of meditation training with feedback from either their own or a matched participant's posterior cingulate cortex (PCC) activity, measured using 7 Tesla fMRI. The experimental group showed stronger functional decoupling of PCC from dorsolateral prefrontal cortex, indicating improved control over disengagement. This led to greater improvements in emotional well-being and mindful awareness during a week of real-world self-guided meditation, supporting the utility of NF-guided meditation training.
April 8, 2024
Saampras Ganesan, Aki Tsuchiyagaito, Greg J. Siegle et al.
2 citations
preprint
Meditation practices, which have been adapted into manualized interventions for conditions like depression, pain, addiction, and anxiety, show therapeutic promise, but their neuroscientific basis remains unclear. Current neuroimaging studies rely on small, heterogeneous datasets that vary in practice types, participant experience, clinical targets, and imaging methods, limiting generalizability and replicability. To address this, the ENIGMA-Meditation consortium was formed as a global collaboration to conduct systematic meta- and mega-analyses of distributed neuroimaging data using standardized methods. This framework aims to improve statistical power and rigorously characterize the neural mechanisms underlying meditation's effects on psychological and cognitive attributes, advancing the field of contemplative neuroscience.
bioRxiv (Cold Spring Harbor Laboratory)
January 3, 2023
Saampras Ganesan, Bradford A. Moffat, Nicholas T. van Dam et al.
1 citation
preprint
Using ultra-high strength 7 Tesla fMRI, a pilot study scanned 10 beginner meditators during focused attention meditation and rest. Meditation significantly reduced activity in Default-mode network hubs—antero-medial prefrontal cortex, posterior cingulate cortex, precuneus—and in visual and thalamic regions, even after adjusting for physiological differences between conditions. State Mindfulness Scale scores significantly increased after the meditation session and remained elevated at a two-week follow-up. The findings support that focused attention meditation attenuates default-mode activity linked to self-referential processing, establishing the feasibility of 7 Tesla fMRI for meditation research.