Cephalization describes the process by which organisms develop a distinct head. The head of a cephalized organism contains a concentrated group of nerves, or brain, that controls the rest of the organism, as well as specialized organs for consumption and perception, like mouths, eyes and ears. Cephalized organisms exhibit a distinct division between parts of the body; they have a front, back, top and bottom. These animals comprise the bulk of animals that are encountered on a daily basis.
sea star following organisms exhibits cephalization
Yes, it could be.
But there are also many other things it could be the result of.
The asthenosphere is denser than the lithosphere.