The glymphatic system is a recently discovered (according to Western Medicine) macroscopic waste clearance system that utilizes a unique system of perivascular channels, formed by astroglial cells, to promote efficient elimination of soluble proteins and metabolites from the central nervous system. (According to NCBI.) Ayurveda on the other hand has had a grasp on what, where and how for about 3,000 years.
It boils down to how our brain detoxes/drains the accumulated toxins. It’s my understanding that this happens at night during sleep and the main drain is on left side of the body. This is one of the reasons Ayurveda recommends sleeping on the left side.
Here is a simple head massage with a good oil that can aid glymph drainage, as well as support cranio sacral fluid.
An excellent next step would be to do one of the lymph face massages and a cup of tea.