The brain's lymphatic system was confirmed to exist only recently, in 2017. https://www.theatlantic.com/health/archive/2017/10/scientists-somehow-just-discover

The brain's lymphatic system was confirmed to exist only recently, in 2017. https://www.theatlantic.com/health/archive/2017/10/scientists-somehow-just-discovered-a-new-system-of-vessels-in-our-brains/542037/ https://www.theatlantic.com/health/archive/2017/10/scientist... https://www.sciencedaily.com/releases/2019/07/190724133649.htm https://www.sciencedaily.com/releases/2019/07/190724133649.h...