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Use an older computer for a long enough time, and you'll find yourself needing to defragment the hard drive. Basically, when a computer needs to store some data, it doesn't necessarily keep it all together, in the same physical storage location. Instead, it looks for the first free spaces it comes across, and sticks bits and pieces of that info in those spaces, while creating for itself a map reminding it where to find all the bits and pieces when it is called upon to recompile the info and bring it back to the user. As files are modified or erased, the distribution of information becomes more and more erratic, and the computer must spend more and more time searching to bring together all the pieces of any one file or program. Worse yet, files and hard drive sectors can become corrupted, causing the loss of all information shoveled into a particular gap. From time to time, the computer user must defragment the hard drive, instructing the computer to go through all those scattered bits of information and reorganize them in a more compact manner. This speeds up later efforts in the process of finding those scattered bits because they are no longer scattered, for the most part, but have been stuck right next to each other.

It is likely that some of the same problems arise within biological systems, but unlike the computer, no mechanism exists to restore order to the scattering of information within an organic entity. There are two prime suspects for this situation in biology, brains, and DNA.

First, the human brain (although this would apply just as well to animal brains). It's workings are little understood, but what is now clear is that physical damage to the brain affects our ability to access or connect certain pieces of information, in short, to think and remember. However, the fact that a surprising amount of brain can be compromised before specific knowledge or memories are lost suggests that the brain has some means of backing up its information, most likely by storing bits of it in different physical locations. So, even when I change your mind by giving you new information, which will physically fill these gaps, there is no telling where that information will go or how it will effect nearby bits of information stuck there long ago. This may be by evolutionary design, where this facility was favorably selected because it provides some survival advantage. Or, it may well be just the same as with a computer hard drive, where bits of info are stuck in the first available gaps purely by default and out of convenience, with no consideration of the problems that may later arise as information becomes increasingly scattered.

The other likely area in need of defragmentation is DNA. Because any given strand of DNA is likely to contain copying errors known as mutations -- and because most mutations are, surprisingly enough, not immediately harmful -- it turns out that DNA is indeed full of old code that does nothing, or nothing good. This old code even pops up once in a while in a malicious fashion, drawn into action by a later bad mutation and introducing things like susceptibility to certain diseases sharply limited to certain ethnic groups, like Sickle Cell Anemia and Tay-Sachs Disease. Like the computer hard drive, information in the DNA becomes scattered over time, with the genetic instructions for branching out a lung, for example, being distributed over several different points of the DNA strand. This distribution increases the opportunities for mutation, as the molecular structures tasked with reading the DNA and carrying out the construction of the blueprint encompassed therein must not only follow the instructions as transmitted, but must piece together certain sequences from bits that are far apart, in the scope of a DNA strand.

How sad it is that biology has not equipped us with any effective means of defragmenting either our increasingly scattered mental processes and products, or the genetic information that we pass on to our heirs. We are instead guaranteed two results: that our ability to cogently recall information will likely fade as we age, and that every generation to succeed us will have DNA that is as scrambled or more scrambled than our own. Our only hopes lie in discovering techniques to control the content of our own minds, and external means to fix both brain and DNA.

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Postscript:

Some fellow noders have contributed helpful thoughts. One writes:

"Dreaming is a memory reclamation process, a biological malloc. It does memory reinforcement, memory 'defragmentation', and a version of packing." This may be true, and it would be a useful process for man to have evolved, and a useful explanation of dreams. I wonder, though, how much "defragmentation" occurs -- my thinking on this is that the ability to retain memories despite some brain damage indicates that the scattered physical locus of information storage serves purposes all its own. On this note, another noder wisely speculates that "there might be some advantages to having fragmentation in thought and memory," and particularly wonders if "having scattered deposits of thought contributes anything to creative, associative thinking."

Yet another noder suggests that ECT or electric shock therapy might play into this process, though I think electroshock is more likely to revitalize existing links rather than reorganizing information.

And nother noder has suggested, "I think your idea about DNA and defrag' is meaningful, but, it should be emphasized only in the context of evolutionary time; on the order of an organism's life it doesn't make much sense." To be clear, I do not suggest that anything changes in our DNA during our lives, and yet I think it quite possible that our brains may, in storing information, accumulate "junk" during our lifetimes.

Finally, on the DNA end, a fellow noder has heard that "some geneticists think that there isn't actually a lot of random duplication in the DNA: that much of it is actually there and gets used under certain conditions. Inert mostly except when needed." This would indeed be interesting, if true, and I'd like to know more about it, but there is no question that genetic information is fractures and scattered within the DNA itself, even if every bit of it is used!!

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