Simultaneous invasive and non-invasive recordings in humans: A novel Rosetta stone for deciphering brain activity.

Simultaneous noninvasive and invasive electrophysiological recordings provide a unique opportunity to achieve a comprehensive understanding of human brain activity, much like a Rosetta stone for human neuroscience. In this review we focus on the increasingly-used powerful combination of intracranial electroencephalography (iEEG) with scalp electroencephalography (EEG) or magnetoencephalography (MEG). We first provide practical insight on how to achieve these technically challenging recordings. We then provide examples from clinical research on how simultaneous recordings are advancing our understanding of epilepsy. This is followed by the illustration of how human neuroscience and methodological advances could benefit from these simultaneous recordings. We conclude with a call for open data sharing and collaboration, while ensuring neuroethical approaches and argue that only with a true collaborative approach the promises of simultaneous recordings will be fulfilled. • Complementary views of simultaneous scalp EEG / MEG and intracranial EEG in humans. • Simultaneous recordings are advancing our understanding of epilepsy. • Simultaneous recordings are improving our understanding of human neuroscience. • Simultaneous recordings provide a ground truth for source localization. • Data sharing within neuroethical boundaries is essential to advance the field. [ABSTRACT FROM AUTHOR]