A biologically inspired repair mechanism for neuronal reconstructions with a focus on human dendrites
Fig 2
Reproduction of biological regrowth of severed class IV Drosophila neurons.
A, The impact of the balancing factor bf demonstrated by repairing a 2D artificially created morphology (left with cut dendrites in magenta). Repairs with different balancing factors on the right (repaired dendrites in green). bf = 0 favours the minimisation of the overall cable length whereas bf = 1 optimises the direct path length towards the soma. B and C, Left, Reference Drosophila larva class IV morphology in which the branches that will be severed deliberately are marked in magenta. B, Right, Example of repaired dendrite where invasion has occurred from adjacent branches marked (green). C, Right, Sample repair where the severed branch regenerated from the cut end (green). D, Morphological statistics of the regrown dendrites from B and C (green) and 498 other random cuts. The repaired morphologies were compared to the original reference neuron (black + magenta in B and C) shown here as the black dashed line, as well as to the cut dendrites (magenta). The root mean square errors (RMSE) indicate the deviation from the reference value as a percentage of the reference value. The examples shown in B and C are represented by the darker square data points. E, Average Sholl distribution for the cut and repaired morphologies from D with standard deviation as shaded area. The reference distribution is shown in black. F, Histogram for 500 regrown dendrites using our repair function, showing the percentage of regenerated branches. G, Percentage of regenerated branches as a function of the size of the removed branch. The points show the actual data as an overlay to the binned normalised histograms of the data points. The bin boundaries are indicated by the black vertical lines. H, Histograms for 500 regrown morphologies as in F but for a higher number of target points N and a higher balancing factor bf.