What are you making?

MEDITACS is a two-year research project exploring what happens in the brain when experienced meditators practice loving-kindness and compassion (LKC) meditation. This is a non-clinical research project and does not involve diagnosis or treatment.

Previous research has shown that long-term meditation practitioners can display strong, synchronized brain activity in the gamma-frequency range during LKC meditation (Lutz et al., 2004). However, most of this research has been observational: we can see that these brain rhythms are associated with LKC meditation, but we do not yet know whether they can be experimentally increased or decreased, and if doing so changes the meditative experience.

MEDITACS will investigate this question by combining EEG with transcranial alternating current stimulation (tACS), a non-invasive technique that applies weak, rhythmic electrical currents through the scalp. A sample of experienced LKC practitioners will take part in three sessions in randomized order: sham stimulation, in-phase gamma-tACS (designed to increase frontoparietal synchronization), and anti-phase gamma-tACS (designed to disrupt that synchronization). Stimulation is delivered with dedicated tACS equipment (DC-STIMULATOR PLUS, neuroConn); OpenBCI hardware is used for EEG acquisition during stimulation-free windows.

The project will also develop an open and reproducible tACS-EEG workflow for studying and modulating gamma-band activity during LKC meditation. This will include practical instructions for setting up the tACS-EEG system, placing electrodes, checking signal quality, recording LKC meditation sessions, and analyzing the resulting data.

Our goal is both to conduct the research described above and to share the practical knowledge gained along the way, so that other researchers, students, and meditation-science groups can reproduce and build on this work.

How are OpenBCI tools being applied?

OpenBCI will provide the EEG acquisition platform used to develop and test the recording workflow for the MEDITACS project.

We plan to use the OpenBCI Cyton + Daisy 16-channel system with the OpenBCI EEG Electrode Cap Kit to record brain activity during stimulation-free periods before and after the tACS intervention. The main focus will be on frontal and parietal regions (primarily F3–P3 and F4–P4), which are key nodes of the large-scale frontoparietal network.

The EEG recordings will be used to examine measures such as gamma power, the ratio of gamma to slower brain rhythms, and frontoparietal gamma synchrony.

A particularly important part of the project is reproducibility. We will document the complete workflow, including cap preparation, tACS montage, EEG electrode placement, signal-quality checks, common sources of artifacts, recording procedures, and data analysis. We will also develop MATLAB/EEGLAB-compatible scripts and practical quality-control recommendations.

These resources will be shared openly through repositories such as GitHub and OSF, as well as through the OpenBCI Community, under open licenses (CC BY 4.0 for documentation and MIT for code).

Why is this important?

Most of what we know about meditation and brain activity comes from observational studies. They show which brain rhythms accompany a meditative state, but not how those rhythms actively contribute to it. MEDITACS addresses this gap by asking whether a brain activity pattern associated with LKC meditation can be causally modulated.

By applying in-phase and anti-phase gamma-tACS during LKC meditation and comparing both with sham stimulation, the project will test whether stimulation designed to strengthen or disrupt frontoparietal gamma synchrony changes both the brain activity recorded afterwards and the meditative experience itself. This moves the question from correlation toward causation. It also treats LKC as a specific mental practice, rather than treating “meditation” as a single, uniform category.

Answering this question requires methodologically demanding procedures. Combining tACS with EEG means dealing with potentially substantial stimulation artifacts, and gamma-band activity recorded from the scalp is easily contaminated by eye and muscle activity. Careful montage design, contact preparation, stimulation-free recording windows, and explicit artifact control are therefore essential, yet these practical details are rarely documented in enough depth to be reproduced.

MEDITACS will document this complete tACS-EEG workflow openly. To this end, the project will produce comprehensive, practical resources that other researchers can inspect, reuse, and adapt: an OpenBCI acquisition guide, an instructional walkthrough, analysis scripts, a signal-quality checklist, and example or synthetic data where participant data cannot be shared. Because they are built on an open-source EEG platform, these resources aim to make rigorous research combining meditation, EEG, and non-invasive neuromodulation accessible to a wider range of research groups.

Who is involved in this project?

Dr. Kilian Abellaneda-Pérez, Ph.D.: Project Lead
Laboratory of Cognitive Neuroscience, University of Lleida (Spain); affiliated researcher at Institut Guttmann, Barcelona (Spain).

Kilian leads the MEDITACS project and will coordinate the experimental, neuromodulation, and open-science components.

Prof. David Bartrés-Faz, Ph.D.: Senior Scientific Advisor
University of Barcelona / IDIBAPS (Spain)

David contributes expertise in neuropsychology, cognitive neuroscience, neuroimaging, brain stimulation, and human neuroscience, and advises on scientific design and data interpretation.

Dr. Ruben Perellón-Alfonso, Ph.D.: EEG and Cognitive Neuroscience Lead
Institute of Neurosciences, University of Barcelona (Spain)

Ruben contributes expertise in EEG acquisition, signal analysis, experimental neurophysiology, and reproducible analysis workflows, as well as in human cognitive neuroscience.

When is the next project update?

MEDITACS runs from September 2026 to September 2028.

The main milestones are:

• Phase I: September – November 2026: OpenBCI hardware setup and technical familiarization (cap fit, electrode preparation, data export, test recordings, and initial montage).
• Phase II: December 2026 – February 2027: Protocol finalization and first version of the OpenBCI acquisition guide.
• Phase III: March – September 2027: Participant recruitment, screening, and initial three-session recordings.
• Phase IV: October 2027 – March 2028: Main data collection and iterative updates to the public workflow.
• Phase V: April – July 2028: Data preprocessing, analysis, and release of the analysis scripts, quality-control checklist, and example or synthetic files.
• Phase VI: August – September 2028: Final release of the complete MEDITACS/OpenBCI workflow and scientific dissemination.

Want to learn more about this project?

Background review: Abellaneda-Pérez, K., Potash, R. M., Pascual-Leone, A., & Sacchet, M. D. (2024). Neuromodulation and meditation: A review and synthesis toward promoting well-being and understanding consciousness and brain. Neuroscience and Biobehavioral Reviews, 166, 105862.
https://doi.org/10.1016/j.neubiorev.2024.105862

Gamma synchrony in long-term LKC practitioners: Lutz, A., Greischar, L. L., Rawlings, N. B., Ricard, M., & Davidson, R. J. (2004). Long-term meditators self-induce high-amplitude gamma synchrony during mental practice. Proceedings of the National Academy of Sciences of the United States of America, 101(46), 16369–16373.
https://doi.org/10.1073/pnas.0407401101

OpenBrain: an open-source platform for interactive 3D brain visualization, created by Mr. Madrigal-Martínez and Dr. Abellaneda-Pérez. The website includes further information on the international team involved and related open-science projects:
https://open-brain-lab.web.app/about

Researcher profile:

• Google Scholar: https://scholar.google.com/citations?user=7tYayQYAAAAJ&hl=es
• LinkedIn: https://www.linkedin.com/in/kilian-abellaneda-p%C3%A9rez-81672889/
• University of Lleida: https://portalrecerca.udl.cat/investigadores/2389314/detalle?lang=en
• Institut Guttmann: https://www.guttmann.com/en/team/kilian-abellaneda

Contact: [email protected] / [email protected]