Electrode pop artefact on EEG

Electrode artefact · Artefacts

Mirror-image steps in Fp1-F3 and F3-C3 and nowhere else: one electrode, no field. Simulated trace, longitudinal bipolar channels. Open in the interactive viewer

What it looks like

A sudden, very steep deflection with a slower decay, confined to one electrode. In a bipolar chain it appears as mirror-image deflections in the two channels sharing that electrode, with no field in the neighbours. ¹¹

What it means at the bedside

Cerebral potentials have a field: they decline gradually across neighbouring electrodes. Something that involves one electrode and nothing else is an artefact until proven otherwise.

ArtefactSingle electrode

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Sources

Britton JW, et al. Electroencephalography (EEG): An Introductory Text and Atlas of Normal and Abnormal Findings in Adults, Children, and Infants. American Epilepsy Society, 2016 (free, NCBI Bookshelf). www.ncbi.nlm.nih.gov/books/NBK390354/

Electrode pop artefact on EEG

What it looks like

What it means at the bedside

Sources

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