MEG-BIDS, the brain imaging data structure extended to magnetoencephalography

Abstract

We present a significant extension of the Brain Imaging Data Structure (BIDS) to support the specific aspects of magnetoencephalography (MEG) data. MEG measures brain activity with millisecond temporal resolution and unique source imaging capabilities. So far, BIDS was a solution to organise magnetic resonance imaging (MRI) data. The nature and acquisition parameters of MRI and MEG data are strongly dissimilar. Although there is no standard data format for MEG, we propose MEG-BIDS as a principled solution to store, organise, process and share the multidimensional data volumes produced by the modality. The standard also includes well-defined metadata, to facilitate future data harmonisation and sharing efforts. This responds to unmet needs from the multimodal neuroimaging community and paves the way to further integration of other techniques in electrophysiology. MEG-BIDS builds on MRI-BIDS, extending BIDS to a multimodal data structure. We feature several data-analytics software that have adopted MEG-BIDS, and a diverse sample of open MEG-BIDS data resources available to everyone.

Figure 1. Overview of MEG-BIDS data organisation.

(a) MEG-BIDS data organisation scheme. MEG-BIDS organises data per study, then participant (subject), followed by sessions, modality and eventually, runs. Note the sidecar files present at all levels of the data hierarchy, conveniently documenting the metadata contents. Further organisational details are illustrated in (b) MEG-BIDS general overview, featuring some the expected types of contents and information pertaining to the study, participant, and related multimodal data.