[Jan. 16] D5 Seminar - Naoyuki Matsumoto (National Institute of Genetics)

December 17 2025

The "D5 Medical & Life Science Seminar" course will be offered by International Research Center for Medical Sciences (IRCMS). It will run from May 2025 to March 2026, with lectures given by scientists who are affiliated with IRCMS or in collaboration with researchers at IRCMS. The lectures will be given once a month, in English, and by leading scientists in the relevant research field. Students will be taught: 1) how normal physiological functions are maintained in the human body; 2) how these systems become abnormal under certain pathophysiologic conditions; 3) why stem cells are important in animal development and homeostasis; 4) how stem cell-based approaches can help us understand disease mechanisms and find potential cure for diseases related to stem cell malfunction (e.g., cancer, aging).

Anyone who wants to join is welcome.
For students who have registered for the course, please check your attendance in Moodle.

Date      : January 16th, 2026 (Friday)
               

Format  : Hybrid (IRCMS lounge and zoom)

Time      : 16:00 - 17:00 (JST)
               

Speaker : Dr. Naoyuki Matsumoto (National Institute of Genetics)

Title : Visualizing activity-dependent circuit remodeling in the mammalian brain

Abstract  :

Even before the onset of sensory experience, sensory organs spontaneously generate neural activity that synchronize the firing among neurons within and between brain areas. The enduring and intriguing question remains of how endogenously generated patterns of spontaneous activity instruct functional circuit refinement at the subcellular levels. To investigate the instructive roles of spontaneous activity in the circuit refinement, I developed a simultaneous in vivo two-photon imaging method combining time-lapse imaging of axon branching in a single axon with dual-color calcium imaging of both single axon activity and neighboring axon activity in awake neonatal mice. I demonstrated that spatiotemporal patterns of spontaneous activity instruct axon branch dynamics at the subcellular level: Axon branches were preferentially added in regions with high levels of synchronous activity with neighboring axons but were eliminated in regions with asynchronous activity. Notably, these observations are consistent with Hebb's predictions summarized as "cells that fire together, wire together" and "out of sync, lose your link", indicating that endogenous patterns of spontaneous activity drive circuit refinement through Hebb's predictions.

Major Papers:

1. Matsumoto N., Barson D., Liang L. and Crair M. (2024) Hebbian instruction of axonal connectivity by endogenous correlated spontaneous activity. Science, 385, 6710, DOI: 10.1126/science.adh7814.
2. Matsumoto N., Tanaka S., Horiike T., Shinmyo Y. and Kawasaki H. (2020) A discrete subtype of neural progenitor crucial for cortical folding in the gyrencephalic mammalian brain. eLife, 9, e54873. doi: 10.7554/eLife.54873.
3. Matsumoto N., Shinmyo Y., Ichikawa Y. and Kawasaki H. (2017) Gyrification of the cerebral cortex requires FGF signaling in the mammalian brain. eLife, 6, e29285. doi: 10.7554/eLife.29285.