 So within your brain, you've got these cavities, these ventricles as they're called. So you have two lateral ventricles, one on each side, a left and a right one. Those flow down into the third ventricle. Third ventricle being this region here with this little hole in it. So within these ventricles is that cerebral spinal fluid. It's going to flow from that third ventricle into your aqueduct, your cerebral aqueduct, which comes to this widened region of the fourth ventricle. From there, it'll go down into the spinal cord, that central canal, which we discussed earlier. You also can see your cornoi plexus sitting right up here on top.