PT - JOURNAL ARTICLE AU - Mary J. Donahue AU - Attila Kaszas AU - Gergely F. Turi AU - Balázs Rózsa AU - Andrea Slézia AU - Ivo Vanzetta AU - Gergely Katona AU - Christophe Bernard AU - George G. Malliaras AU - Adam Williamson TI - Multimodal Characterization of Neural Networks Using Highly Transparent Electrode Arrays AID - 10.1523/ENEURO.0187-18.2018 DP - 2018 Nov 01 TA - eneuro PG - ENEURO.0187-18.2018 VI - 5 IP - 6 4099 - http://www.eneuro.org/content/5/6/ENEURO.0187-18.2018.short 4100 - http://www.eneuro.org/content/5/6/ENEURO.0187-18.2018.full SO - eNeuro2018 Nov 01; 5 AB - Transparent and flexible materials are attractive for a wide range of emerging bioelectronic applications. These include neural interfacing devices for both recording and stimulation, where low electrochemical electrode impedance is valuable. Here the conducting polymer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is used to fabricate electrodes that are small enough to allow unencumbered optical access for imaging a large cell population with two-photon (2P) microscopy, yet provide low impedance for simultaneous high quality recordings of neural activity in vivo. To demonstrate this, pathophysiological activity was induced in the mouse cortex using 4-aminopyridine (4AP), and the resulting electrical activity was detected with the PEDOT:PSS-based probe while imaging calcium activity directly below the probe area. The induced calcium activity of the neuronal network as measured by the fluorescence change in the cells correlated well with the electrophysiological recordings from the cortical grid of PEDOT:PSS microelectrodes. Our approach provides a valuable vehicle for complementing classical high temporal resolution electrophysiological analysis with optical imaging.