Abstract
Recent years have seen substantial developments in technology for imaging neural circuits, raising the prospect of large scale imaging studies of neural populations involved in information processing, with the potential to lead to step changes in our understanding of brain function and dysfunction. In this article we will review some key recent advances: improved fluorophores for single cell resolution functional neuroimaging using a two photon microscope; improved approaches to the problem of scanning active circuits; and the prospect of scanless microscopes which overcome some of the bandwidth limitations of current imaging techniques. These advances in technology for experimental neuroscience have in themselves led to technical challenges, such as the need for the development of novel signal processing and data analysis tools in order to make the most of the new experimental tools. We review recent work in some active topics, such as region of interest segmentation algorithms capable of demixing overlapping signals, and new highly accurate algorithms for calcium transient detection. These advances motivate the development of new data analysis tools capable of dealing with spatial or spatiotemporal patterns of neural activity, that scale well with pattern size.
Highlights
Recent years have seen substantial developments in technology for imaging neural circuits, raising the prospect of large scale imaging studies of neural populations involved in information processing, with the potential to lead to step changes in our understanding of brain function and dysfunction
A number of third-generation calcium indicators have since been developed with a wide range of excitation spectra and calcium affinities, including the currently popular dyes OregonGreen BAPTA (OGB) and fluo-4 [25], whose fluorescence increases in line with neuronal calcium elevations upon two-photon excitation
The early types of GCaMP proteins had limited application due to their slow response kinetics and low signal-to-noise ratios in comparison to OGB, meaning that neuroscientists had to compromise between highly sensitive probes delivered via invasive injection methods, or genetically encoded calcium indicators (GECIs) with poor sensitivity delivered by non-invasive genetic methods
Summary
Understanding the principles by which neural circuits process information is one of the central problems of modern neuroscience. A necessary step in reverse engineering the functional principles of neural circuits is to simultaneously observe the activity of local circuit elements - down to the resolution of individual neuronal cell bodies, and potentially even of subcellular elements such as dendrites. Multi-electrode array electrophysiological recording technology offers greater spike timing precision and accuracy at detection of individual action potentials than current optical approaches. Use of this technology for spatial localisation and cell type classification of recorded cells is still a work in progress [3]. In this article we will review recent advances in activity dependent fluorophores, scanning algorithms for observing neural circuit activity, scanless approaches to imaging neural circuits, and recent developments in data analysis algorithms for two photon imaging
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
