This great zone of cerebral activity is where plans are made to speak, write, throw a baseball, or pick up a dish from the table. - Michael S. Gazzaniga

As evolutionary neurobiologists Leah Krubitzer and Jon Kaas put it, Although the phenotype generated is context-dependent, the ability to respond to the context has a genetic basis. . . . In essence, the Baldwin effect is the evolution of the ability to respond optimally to a particular environment. Thus, genes for plasticity evolve, rather than genes for a particular phenotypic characteristic, although selection acts upon the phenotype.

As in any layered system, however, the system can become jeopardized if a core component that transfers information from one layer to another malfunctions. In the case of biological tissue, if the kinds of proteins that connect cells together are defective, then information may not be able to transfer from the individual-cell layer to the tissue layer, and the entire system could shut down. While not perfect, the layered design of biological systems is advantageous because it minimizes the number of points in the system that, if attacked, would result in catastrophic damage, and it limits the effects of attacks at other points.

The first visit involves the challenge of the unknown, curiosity, adventure, often youth, and sometimes adrenaline. On a revisit, you are returning older, with more life experience under your belt, to familiar territory; it is not so challenging, your curiosity is not so piqued, you know more or less what to expect, you have less adrenaline pumping. You feel different, not necessarily worse or better, just different. This is true not just for returning to locales but also for trying to recapture any past experience.