DOI: 10.1101/178657Aug 20, 2017Paper

Innovations orthogonalization: a solution to the major pitfalls of EEG/MEG "leakage correction"

BioRxiv : the Preprint Server for Biology
Roberto D Pascual-MarquiMasafumi Yoshimura

Abstract

The problem of interest here is the study of brain functional and effective connectivity based on non-invasive EEG-MEG inverse solution time series. These signals generally have low spatial resolution, such that an estimated signal at any one site is an instantaneous linear mixture of the true, actual, unobserved signals across all cortical sites. False connectivity can result from analysis of these low-resolution signals. Recent efforts toward "unmixing" have been developed, under the name of "leakage correction". One recent noteworthy approach is that by Colclough et al (2015 NeuroImage, 117:439-448), which forces the inverse solution signals to have zero cross-correlation at lag zero. One goal is to show that Colclough's method produces false human connectomes under very broad conditions. The second major goal is to develop a new solution, that appropriately "unmixes" the inverse solution signals, based on innovations orthogonalization. The new method first fits a multivariate autoregression to the inverse solution signals, giving the mixed innovations. Second, the mixed innovations are orthogonalized. Third, the mixed and orthogonalized innovations allow the estimation of the "unmixing" matrix, which is then finally used to...Continue Reading

Related Concepts

Related Feeds

BioRxiv & MedRxiv Preprints

BioRxiv and MedRxiv are the preprint servers for biology and health sciences respectively, operated by Cold Spring Harbor Laboratory. Here are the latest preprint articles (which are not peer-reviewed) from BioRxiv and MedRxiv.

Related Papers

BioRxiv : the Preprint Server for Biology
Roberto D Pascual-MarquiMasafumi Yoshimura
Conference Proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society
J I Padilla-BuriticáG Castellanos-Domínguez
IEEE Transactions on Bio-medical Engineering
Hilde M HuizengaRaoul P P P Grasman
Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
Roberto D Pascual-MarquiToshihiko Kinoshita
© 2021 Meta ULC. All rights reserved