Comparative study of voxel-based statistical analysis methods for fluorescently labelled and light sheet imaged whole-brain samples

Light sheet microscopy of fluorescently labelled and optically cleared intact organs is a novel approach which enables to visualize structure and function of the brain in 3D. The methodology is gaining popularity in the neuroscience community and dedicated algorithms are being developed for segmenting and quantifying different neurological markers. However, comparisons of marker characteristics between the study groups are conventionally performed by conducting statistical testing for every atlas-defined brain region. While this statistical approach yields viable results, it is biased by the region delineations and does not provide information on the signal properties at a voxel level. In this work, we convert the 3D histological signal from segmented c-Fos + cells into a format suitable for conducting voxel-wise group comparisons and demonstrate the potential of a recent technique, probabilistic threshold-free cluster enhancement method, in a brief comparative study of six different approaches to voxel-based statistical analysis.