Brain Topography

, Volume 28, Issue 5, pp 647–656 | Cite as

Novel Multipin Electrode Cap System for Dry Electroencephalography

  • P. FiedlerEmail author
  • P. Pedrosa
  • S. Griebel
  • C. Fonseca
  • F. Vaz
  • E. Supriyanto
  • F. Zanow
  • J. Haueisen
Original Paper


Current usage of electroencephalography (EEG) is limited to laboratory environments. Self-application of a multichannel wet EEG caps is practically impossible, since the application of state-of-the-art wet EEG sensors requires trained laboratory staff. We propose a novel EEG cap system with multipin dry electrodes overcoming this problem. We describe the design of a novel 24-pin dry electrode made from polyurethane and coated with Ag/AgCl. A textile cap system holds 97 of these dry electrodes. An EEG study with 20 volunteers compares the 97-channel dry EEG cap with a conventional 128-channel wet EEG cap for resting state EEG, alpha activity, eye blink artifacts and checkerboard pattern reversal visual evoked potentials. All volunteers report a good cap fit and good wearing comfort. Average impedances are below 150 kΩ for 92 out of 97 dry electrodes, enabling recording with standard EEG amplifiers. No significant differences are observed between wet and dry power spectral densities for all EEG bands. No significant differences are observed between the wet and dry global field power time courses of visual evoked potentials. The 2D interpolated topographic maps show significant differences of 3.52 and 0.44 % of the map areas for the N75 and N145 VEP components, respectively. For the P100 component, no significant differences are observed. Dry multipin electrodes integrated in a textile EEG cap overcome the principle limitations of wet electrodes, allow rapid application of EEG multichannel caps by non-trained persons, and thus enable new fields of application for multichannel EEG acquisition.


Biopotential electrode EEG ECG Dry electrode 



This work was financially supported by the German Federal Ministry of Education and Research (03IPT605A), the German Academic Exchange Service (D/57036536), the Thüringer Aufbaubank and the European Social Fund (2012 FGR 0014), and the European Union (FP7-PEOPLE Marie Curie IAPP project 610950).


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Institute of Biomedical Engineering and InformaticsTechnische Universität IlmenauIlmenauGermany
  2. 2.Departamento de Engenharia Metalúrgica e de Materiais, Faculdade de EngenhariaUniversidade do PortoPortoPortugal
  3. 3.Department of Mechanism TechnologyTechnische Universität IlmenauIlmenauGermany
  4. 4.Centro de FísicaUniversidade do MinhoBragaPortugal
  5. 5.IJN-UTM Cardiovascular Engineering CentreUniversiti Teknologi MalaysiaJohor BahruMalaysia
  6. 6.eemagine Medical Imaging Solutions GmbHBerlinGermany
  7. 7.Department of Neurology, Biomagnetic CenterJena University HospitalJenaGermany

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