Cerebrospinal fluid flows between the pia and arachnoid membranes that cover the brain. This fluid provides nutrition for brain and helps cushion it from bumps. The outermost brain layer is known as the cerebral cortex. Quite smooth at birth, it soon becomes wrinkled and folded until it resembles a pinkish gray walnut. This part of the brain is home to complex high-level executive functions so-called (e.g., creativity, complex thinking, planning, reasoning, language, intuition decision-making, imagination) that distinguish the brains of homo sapiens from the brains of other creatures—although some are voicing concerns about behaviors exhibited by some homo sapiens and whether or not they reflect complex high-level executive functions. Perhaps the bottom line is that you get one shot (so far) of a brain full of neurons. How well you take care of them has a great deal to do with how successful you are over a lifetime and how long you live. Get smart about your brain!