A Multi-Channel, Flex-Rigid ECoG Microelectrode Array for Visual Cortical Interfacing

Sensors

Elena Tolstosheeva²  Vໜtor Gordillo-González¹  Volker Biefeld²  Ludger Kempen²  Sunita Mandon¹  Andreas K. Kreiter¹ 

[1] Institute for Brain Research, Center for Cognitive Sciences, University of Bremen, Bremen 28359, Germany; E-Mails:;Institute for Microsensors, Actuators and Systems (IMSAS), Microsystems Center Bremen (MCB), University of Bremen, Bremen 28359, Germany; E-Mails:

关键词: biomedical electrodes;    implantable biomedical devices;    in vivo;    neural microtechnology;    neural prosthesis;   

DOI  :  10.3390/s150100832

来源: mdpi

【 摘 要 】

High-density electrocortical (ECoG) microelectrode arrays are promising signal-acquisition platforms for brain-computer interfaces envisioned, e.g., as high-performance communication solutions for paralyzed persons. We propose a multi-channel microelectrode array capable of recording ECoG field potentials with high spatial resolution. The proposed array is of a 150 mm² total recording area; it has 124 circular electrodes (100, 300 and 500 μm in diameter) situated on the edges of concentric hexagons (min. 0.8 mm interdistance) and a skull-facing reference electrode (2.5 mm² surface area). The array is processed as a free-standing device to enable monolithic integration of a rigid interposer, designed for soldering of fine-pitch SMD-connectors on a minimal assembly area. Electrochemical characterization revealed distinct impedance spectral bands for the 100, 300 and 500 μm-type electrodes, and for the array's own reference. Epidural recordings from the primary visual cortex (V1) of an awake Rhesus macaque showed natural electrophysiological signals and clear responses to standard visual stimulation. The ECoG electrodes of larger surface area recorded signals with greater spectral power in the gamma band, while the skull-facing reference electrode provided higher average gamma power spectral density (γPSD) than the common average referencing technique.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.