The morphology of alpha ganglion cells in mammalian species: a fractal analysis study

Fractal analysis has already found widespread application in theuroscience and is being used in many other area. In this study we applied fractal analysis on two dimensional images of the alfa retinal ganglion cells from various species, in order to investigate the morphology of these cells and to test whether there are differences in alpha cell morphology between the species. The binary and skeletonised fractal dimension (Dbin and Dskel) were calculated for alpha retinal ganglion cells of wild and domestic animals. The aim was to determine whether the complexity of the branching pattern, which reflects the cell's function is reflected in the animal's ecology. The highest mean Dbin was obtained for the guanaco and Niglau antilope, while the smallest mean value was found for the ferret. On the other hand, the highest and smallest mean Dskel was found for the chinchilla and ferret, respectively. For the domestic animals the highest mean Dbin was obtained for the Guinea pig, dog and ox, while the smallest mean was found in the pig. As for the mean Dskel the highest and smallest value was found for the dog and pig, respectively. The results showed that the fractal dimension represents a parameter which is of relevance for inter-species comparisons of retinal ganglion cell populations.