3D Reference Frames for Precise Registration of Neuronal Morphologies

Rajeev Narayanan1, Mike Guest1, Aman Maharjan1, Amina Javadova1, Marcel Oberlaender1

1 Center of Advanced European Studies and Research

Identifying the structural organization of neuronal networks requires combining anatomical data acquired from different individuals and across spatial resolutions. The task of combining such data is challenging owing to the variability across individual brain sizes as well as experimental procedures used to generate the data. To address this challenge, digital atlases are currently developed for a variety of species.  These approaches are commonly based on reconstructions of an entire brain (e.g. MRI images) and provide different transformation routines to register anatomical data to it.

Here we present an alternate approach that enables registering anatomical data onto specific anatomically defined sub regions of the brain. We exemplify our approach on different areas of the rat brain that are involved in tactile information processing: facial nucleus in the brain stem, primary somatosensory cortex and motor cortex. We demonstrate that reconstructions of individual neuronal morphologies can be registered onto these regions with a precision of 50-60µm. When compared to whole brain registration approaches, this results in an increase in precision by almost one order of magnitude. Our approach is publicly available online, which will facilitate comparing anatomical data from different modalities and labs, thereby deepening our understanding of structural organization of local and brain wide neuronal networks.