Answer
No.
Work Step by Step
The buoyant force is 14.5 N because the brain takes up the space of 14.5 N of fluid. As long as there is just enough fluid surrounding the brain to press on it, the 14.5 buoyant force is applied. Try it by floating a small object in a container that is barely larger than the object itself, or look up photos of large ships floating in locks.
