HarMNqEEG boutique descriptor

This is the Cbrain boutique descriptor.

 Tool Description:

This toolbox extends frequency domain quantitative electroencephalography (qEEG) methods pursuing higher sensitivity to detect Brain Developmental Disorders. Prior qEEG work lacked integration of cross-spectral information omitting important functional connectivity descriptors. Lack of geographical diversity precluded accounting for site-specific variance, increasing qEEG nuisance variance. We ameliorate these weaknesses by (i) Creating lifespan Riemannian multinational qEEG norms for cross-spectral tensors. These norms result from the HarMNqEEG project fostered by the Global Brain Consortium. We calculated the norms with data from 9 countries, 12 devices, and 14 studies, including 1564 subjects. Developmental equations for the mean and standard deviation of qEEG traditional and Riemannian DPs were calculated using additive mixed-effects models. We demonstrate qEEG “batch effects” and provide methods to calculate harmonized z-scores. (ii) We also show that harmonized Riemannian norms produce z-scores with increased diagnostic accuracy. These results contribute to developing bias-free, low-cost neuroimaging technologies applicable in various health settings. In this first version, we limited the harmonized qEEG to the 19 channels of the S1020 montage.

At the present, the toolbox accepts the input EEG data in EEG-BIDS, EDF+, BDF+, PLG, EEGLAB SET format, and a predefined TEXT format. In the case of not EEG-BIDS structure, the derivatives are stored in the same directory where the raw EEG file is located.

The toolbox also contains the definition of the Harmonized qEEG derivatives for the EEG-BIDS format. The derivatives are stored in the BIDS structure compliant with the BIDS definition for the derivatives, in the Hierarchical Data Format (HDF). The functions for creating and loading the HarMNqEEG derivatives can be found in the directory "derivatives_functions".