TOWARDS CO-LOCALISED MICROELECTRODE ARRAY RECORDINGS AND TWO-PHOTON MICROSCOPY
Domokos Meszéna1, 3, 1,Gábor Orbán1, 2, Kinga Réka Tasnády2, István Ulbert1, 3 and Gergely Márton1, 2
The simultaneous application of two-photon imaging and electrophysiological recordings within the same field of view allows the observation of the bioelectrical activity of the nervous system in a high temporal and spatial resolution at the same time. The utilization of implanted microelectrode arrays can be more complex and precise by the three dimensional monitoring of the morphological features surrounding the electrodes. In this study, neocortical slices were prepared from mice brains expressing GCaMP6 genetically encoded calcium indicator, which are suitable for in vitro two-photon imaging. Multi-channel silicon probes were implanted within the same field of view of the two-photon imaging and simultaneous recordings were performed. The imaging laser generated large photoelectrical artefacts in the electrophysiological recordings that made the data analysis and the noise filtering challenging. A development of complex filtering algorithms was required. Our novel filtering method proved to be capable of artefact filtering from simultaneous two-photon imaging and electrophysiological measurements and it allowed us to detect and follow the same single unit activities before, during and after the laser scanning.