Self Comes to Mind

body-relatedness of the brain.
    One other distinction must be made between neurons and other body cells. To the best of our knowledge, neurons do not reproduce—that is, they do not divide. Nor do they regenerate, or at least not to a significant extent. Practically all other cells in the body do, although the cells of the lenses in our eyes and the muscle fiber cells of the heart are exceptions. It would not be a good idea for such cells to divide. If cells in the lens were to undergo division, the transparency of the medium would likely be affected during the process. If cells in the heart were to divide (even only one sector at a time, a bit like the carefully planned remodeling of a house), the pumping action of the heart would be severely compromised, much as it is when a myocardial infarct disables a sector of the heart and unbalances its chambers’ fine coordination. What about the brain? Although we lack a complete understanding of how neuron circuits maintain memories, division of neurons would probably disrupt the records of a lifetime of experience that are inscribed, by learning, in particular patterns of neurons firing in complex circuits. For the same reason, division would also disrupt the sophisticated know-how that is inscribed in circuits by our genome from the get-go and that tells the brain how to coordinate the operations of life. Division of neurons might spell the end of species-specific life regulation and would possibly not allow behavioral and mental individuality to develop, let alone become identity and personhood. The plausibility of this dire scenario is in the known consequences of damage to certain neuron circuits as caused by stroke or Alzheimer’s disease.
    The division of most other cells in our bodies is highly regimented, so as not to compromise the architecture of the varied organs and the overall architecture of the organism. There is a Bauplan that must be adhered to. Throughout the life span, a continuous restoration is going on rather than genuine remodeling. No, we do not knock down walls in our body house; nor do we build a new kitchen or add a guest wing. The restoration is very subtle, quite meticulous. For a good part of our lives, the substitution of cells is so perfectly achieved that even our appearance remains the same. But when one considers the effects of aging relative to the external appearance of our organism or to the operation of our internal system, one realizes that the substitutions become gradually less perfect. Things are not quite in the same place. The skin of the face ages, muscles sag, gravity intervenes, organs may not work quite so well. And that is when a good Beverly Hills plastic surgeon and efficient concierge medicine should enter the picture.
Staying Alive
     
    What does it take for a living cell to stay alive? Quite simply, it takes good housekeeping and good external relations, which is to say good management of the myriad problems posed by living. Life, in a single cell as well as in large creatures with trillions of them, requires the transformation of suitable nutrients into energy, and that, in turn, calls for the ability to solve several problems: finding the energy products, placing them inside the body, converting them into the universal currency of energy known as ATP, disposing of the waste, and using the energy for whatever the body needs to continue this same routine of finding the right stuff, incorporating it, and so forth. Procuring nutrition, consuming and digesting it, and allowing it to power a body—those are the issues for the humble cell.
    The mechanics of life management are crucial because of its difficulty. Life is a precarious state, made possible only when a large number of conditions are met simultaneously within the body’s interior. For example, in organisms such as ours, the amounts of oxygen and CO 2 can vary only within a narrow range, as can the acidity of the bath in which chemical molecules of every sort travel from cell to cell (the pH). The same applies to temperature, whose variations we are keenly aware of when we have a fever or, more commonly, when we complain of the weather’s being too hot or too cold; it also applies to the amount of fundamental nutrients in circulation—sugars, fats, proteins. We feel discomfort when the variations depart from the nice and narrow range, and we feel quite agitated if we go for a very long time without doing something about the situation. These mental states