A simple reason why beamformer may (not) remove the tACS-induced artifact in MEG

Research output: Contribution to journalArticleScientificpeer-review


Research units


Transcranial alternating current simulation (tACS) combined synchronously
with magnetoencephalography (MEG) could be a useful tool for studying brain oscillations and their relation to cognitive functions, but the method, however, suffers from large tACS-induced MEG artifacts. Conventional beamformer methods have been suggested for removing - or at least reducing - the artifact, but its functioning principle is not yet fully understood. We demonstrate the reason behind the beamformer’s ability to remove/reduce the tACS artifact (and other mutually correlated noise sources) with simple theoretical reasoning and simulations. In addition, at odds with previous suggestions, we show how the imperfections of this removal method could be explained with basic linear algebra without any need to consider nonlinear effects.


Original languageEnglish
Pages (from-to)e66-e67
Number of pages2
JournalBrain Stimulation
Issue number4
Publication statusPublished - Aug 2017
MoE publication typeA1 Journal article-refereed

ID: 16408890