X-ray nanoscope with synapse resolution for neuronal circuit reconstruction

Neural circuits in the central nervous system are the substrate of various high-order brain functions. Anatomical and functional graph structures of neural networks with actual connections will provide us with perspectives to elucidate the brain complex system. Here, we aim to develop a three-dimensional mouse brain atlas of neural circuits using high resolution x-ray tomography by synchrotron radiation. It will not only identify a large number of synapses but also clarify the structure of neuronal networks for understanding the most complicated organ in the body. In this study, a nano-resolution full-field x-ray microscope revealed nerve fibers and organelles including mitochondria and synapses in the mouse cerebral cortex. Fig. a shows chematic layout of the x-ray optical system and Fig. b demonstrated soft x-ray micrograph of the neural tissue slice. In the near future, we will utilize that information to begin deciphering the wiring diagram of the brain by applying the nano-resolution x-ray tomography.