In the cerebral cortex, a spacious neuron layer that performs various functions such as movement, vision, hearing, and language is formed.However, how this area is secured has never been investigated concretely.

　In this group, there may be something like "flow" in the nascent brain that is observed in various events on the earth, such as the movement of continents and the expansion of the earth toward the sea. I made the hypothesis.Then, when we observed the neurons that make up the layer called the preplate in the early embryonic period, we found that it "flowed" from the dorsal side to the ventral side (preplate flow).

　Next, in order to clarify the significance of the preplate flow, we investigated the formation of the cerebral cortex when only the neurons that make up the preplate were killed.As a result, the structure called "radial fiber", which serves as a guide for cells in the cerebrum, cannot become the original divergent, and the neuron layer called "cortical plate" extends and spreads to the ventral side as it should. I can't do it anymore.In addition, it was found that mice deprived of the preplate flow in the early embryonic period develop abnormalities in which the pattern of territorial formation in the cerebral cortex shifts to the dorsal side of the original location and shrinks after birth.

　From these results, it was clarified that the dorsal → ventral preplate flow is extremely important for the cerebral development process and, by extension, the functioning of the spacious cerebral cortex.

　It can be said that this is the first result of clarifying that a principle similar to the physical phenomenon observed on the earth is involved in the developmental phenomenon of making the cerebrum wide.

Paper information:[Cell Reports] Dorsal-to-ventral cortical expansion is physically primed by ventral streaming of early embryonic preplate neurons