Novel flexible Dry multipin electrodes for EEG: Signal quality and interfacial impedance of Ti and TiN coatings

Abstract

Conventional Silver/Silver-Chloride electrodes are inappropriate for routine high-density EEG and emerging new fields of application like brain computer interfaces. A novel multipin electrode design is proposed. It enables rapid and easy application while maintaining signal quality and patient comfort. The electrode design is described and impedance and EEG tests are performed with Titanium and Titanium Nitride coated electrodes. The results are compared to conventional reference electrodes in a multi-volunteer study. The calculated signal parameters prove the multipin electrode concept to reproducibly acquire EEG signal quality comparable to Ag/AgCl electrodes. The promising results encourage further investigation and can provide a technological base for future preparation-free multichannel EEG systems.

EEG Data Quality: Determinants and Impact in a Multicenter Study of Children, Adolescents, and Adults with Attention-Deficit/Hyperactivity Disorder (ADHD)

“…Although the EEG represents an established method for assessing neuronal activity, systematic explorations of signal contamination are rather scarce and existing reports of data quality measures are often inconsistent. Typically, studies only indirectly address data quality by reporting impedance cut-offs (such as < 20 kΩ at each electrode location) or standard cut-off values for the least-acceptable absolute number of sweeps included per participant for subsequent analyses [ 8 , 9 , 10 ]. Further studies calculated analytical indices using complex models to explicitly assess EEG data quality [ 11 , 12 ].…”

A study on quality assessment of the surface EEG signal based on fuzzy comprehensive evaluation method

“…EEG signal quality evaluation research is still at the early stage of development. The most commonly used method for evaluating the quality of the EEG signal is the impedance method, that is, applying the impedance between electrodes and human body to judge the EEG signal acquisition quality [5][6][7][8]. However, this method has limitations, for instance, when using this method, the surface EEG signal needs to be collected in a specific circumstance, which may shield most of the interference, such as power frequency interference and so on.…”

Impedance analysis of ZnO nanowire coated dry EEG electrodes

“…[14] Titanium/Titanium Nitride or carbon nanotube has also been used to coat electrodes. [15][16][17] Electrodes made of silver-coated polymer bristles have been proposed and shown to be more conductive, flexible and comfortable. [7] Our group has developed a novel dry EEG * Correspondence: Wenyan Jia; Email: wej6@pitt.edu; Address: Department of Neurosurgery, University of Pittsburgh, PA, USA.…”

“…In recent years, different types of dry electrodes, such as polymer foam electrode, solid-gel electrode, textile electrode, pin-shaped metallic electrode have been developed. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] To evaluate the performance of these electrodes, comparing the spontaneous EEG signals (e.g., the alpha wave) or the evoked potential acquired by the dry electrodes and conventional Ag/AgCl electrodes qualitatively or quantitatively is a common approach. [2][3][4][11][12][13] However, the signal quality is not only affected by the electrode itself, but also the acquisition components of the EEG system.…”