  Scientists construct connectomes, comprehensive descriptions of neuronal
connections across a brain, in order to better understand and model brain
function. Interactive visualizations of these pathways would enable exploratory
analysis of such information flows. Current tools can be used to see individual
tracing experiments which are used to build mesoscale connectomes of the mouse
brain, but not the brain network itself. We present a connectivity
visualization program called BrainViewer, which we use with a high-resolution
mouse cortical connectome. This has the ability to display connectomes from
other datasets when they become available and compare spatial connectivity
across multiple brain structures. Our tool, optimized for speed and
portability, presents a GUI visualization in 2-D top view and flatmap
projections, allowing users to select and explore the connections of every
source voxel to everywhere else in the cortex. Anatomists and other
neuroscientists will find BrainViewer useful for building understanding beyond
the known topography of cortical connectivity.
