And the cell on the right there fires whenever there's a boundary to the south, whether it's the drop at the edge of the table or a wall or even the gap between two tables that are pulled apart.
而右面的细胞 则是在老鼠南面出现边界时响应， 不论这边界是桌布的垂帘还是一堵墙 甚至是两个被隔开的桌子之间的间隙。