A high-density 256-channel cap for dry electroencephalography

• Type: Article in International Scientific Journal
• Date: 2022

Authors

Fiedler, P (Author) Other; C. Fonseca (Author) FEUP; Supriyanto, E (Author) Other; Zanow, F (Author) Other; Haueisen, J (Author) Other

Journal

Title: Human Brain Mapping

Vol. 43

Pages: 1295-1308

ISSN: 1065-9471

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 16 Citations

Scopus - 21 Citations

Other information

Authenticus ID: P-00V-Q6C

DOI: 10.1002/hbm.25721

Abstract (EN): High-density electroencephalography (HD-EEG) is currently limited to laboratory environments since state-of-the-art electrode caps require skilled staff and extensive preparation. We propose and evaluate a 256-channel cap with dry multipin electrodes for HD-EEG. We describe the designs of the dry electrodes made from polyurethane and coated with Ag/AgCl. We compare in a study with 30 volunteers the novel dry HD-EEG cap to a conventional gel-based cap for electrode-skin impedances, resting state EEG, and visual evoked potentials (VEP). We perform wearing tests with eight electrodes mimicking cap applications on real human and artificial skin. Average impedances below 900 k omega for 252 out of 256 dry electrodes enables recording with state-of-the-art EEG amplifiers. For the dry EEG cap, we obtained a channel reliability of 84% and a reduction of the preparation time of 69%. After exclusion of an average of 16% (dry) and 3% (gel-based) bad channels, resting state EEG, alpha activity, and pattern reversal VEP can be recorded with less than 5% significant differences in all compared signal characteristics metrics. Volunteers reported wearing comfort of 3.6 +/- 1.5 and 4.0 +/- 1.8 for the dry and 2.5 +/- 1.0 and 3.0 +/- 1.1 for the gel-based cap prior and after the EEG recordings, respectively (scale 1-10). Wearing tests indicated that up to 3,200 applications are possible for the dry electrodes. The 256-channel HD-EEG dry electrode cap overcomes the principal limitations of HD-EEG regarding preparation complexity and allows rapid application by not medically trained persons, enabling new use cases for HD-EEG.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 14