title: Comparative performance of a genetically-encoded voltage indicator and a blue voltage sensitive dye for large scale cortical voltage imaging.
abstract: Traditional small molecule voltage sensitive dye indicators have been a powerful tool for monitoring large scale dynamics of neuronal activities but have several limitations including the lack of cell class specific targeting, invasiveness and difficulties in conducting longitudinal studies. Recent advances in the development of genetically-encoded voltage indicators have successfully overcome these limitations. Genetically-encoded voltage indicators (GEVIs) provide sufficient sensitivity to map cortical representations of sensory information and spontaneous network activities across cortical areas and different brain states. In this study, we directly compared the performance of a prototypic GEVI, VSFP2.3, with that of a widely used small molecule voltage sensitive dye (VSD), RH1691, in terms of their ability to resolve mesoscopic scale cortical population responses. We used three synchronized CCD cameras to simultaneously record the dual emission ratiometric fluorescence signal from VSFP2.3 and RH1691 fluorescence. The results show that VSFP2.3 offers more stable and less invasive recording conditions, while the signal-to-noise level and the response dynamics to sensory inputs are comparable to RH1691 recordings.
authors.affiliation: Department of Neurophysiology, Hamamatsu University School of Medicine Hamamatsu, Japan ; Laboratory for Neuronal Circuit Dynamics, RIKEN Brain Science Institute Wako City, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Mutoh
authors.affiliation: Laboratory for Neuronal Circuit Dynamics, RIKEN Brain Science Institute Wako City, Japan ; Centre for Global Communication Strategies The University of Tokyo, Tokyo Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Mishina
authors.affiliation: Division of Brain Sciences, Department of Medicine, Imperial College London London, UK.
authors.forename: Yasir
authors.initials: Y
authors.lastname: Gallero-Salas
authors.affiliation: Laboratory for Neuronal Circuit Dynamics, RIKEN Brain Science Institute Wako City, Japan ; Division of Brain Sciences, Department of Medicine, Imperial College London London, UK.
authors.forename: Thomas
authors.initials: T
authors.lastname: Knöpfel
keywords: cortex; genetically encoded sensors; mouse models; optical imaging; voltage-sensitive dye imaging