Vertebrate brains have an outer layer of “gray matter” over the inner “white matter.” Why is this? “By borrowing mathematical tools from theoretical physics,” a press release from Cold Spring Harbor Laboratory announced, two researchers found out.
Posted on 01/14/2006 8:31:15 PM PST by bondserv
Why Your Brain Has Gray Matter, and Why You Should Use It 01/13/2006
Vertebrate brains have an outer layer of “gray matter” over the inner “white matter.” Why is this? “By borrowing mathematical tools from theoretical physics,” a press release from Cold Spring Harbor Laboratory announced, two researchers found out.
Based on no fewer than 62 mathematical equations and expressions, the theory provides a possible explanation for the structure of various regions including the cerebral cortex and spinal cord. The theory is based on the idea that maximum brain function requires a high level of interconnectivity among brain neurons but a low level of delays in the time it takes for signals to move through the brain. (Emphasis added in all quotes.)Their paper was published in PLoS Computational Biology.1 Despite the implicit deduction that the brain appears optimally designed, the authors looked to the random, unguided processes of evolution to explain how it got that way. Notice the first word in this next sentence: “Assuming that evolution maximized brain functionality, what is the reason for such segregation?” they asked. Did the claim of evolution ever get past the assumption stage?
Gray matter contains neuron somata, synapses, and local wiring, such as dendrites and mostly nonmyelinated axons. White matter contains global, and in large brains mostly myelinated, axons that implement global communication. What is the evolutionary advantage of such segregation? Networks with the same local and global connectivity could be wired so that global and local connections are finely intermixed. Since such design is not observed, and invoking an evolutionary accident as an explanation has agnostic flavor, we searched for an explanation based on the optimization approach, which is rooted in the evolutionary theory.Their use of the term agnostic is not what most people think (i.e., uncertainty about the existence of God), but a-gnostic, or “not knowing.” They recognize that saying it was a lucky accident is a non-answer. Rather, they assumed that evolutionary theory provides a pathway through the randomness toward optimization. They stated again that this was their starting assumption:
We started with the assumption that evolution “tinkered” with brain design [sic] to maximize its functionality. Brain functionality must benefit from higher synaptic connectivity, because synaptic connections are central for information processing as well as learning and memory, thought to manifest in synaptic modifications. However, increasing connectivity requires adding wiring to the network, which comes at a cost. The cost of wiring is due to metabolic energy required for maintenance and conduction, guidance mechanisms in development, conduction time delays and attenuation, and wiring volume.Sounds like a lot of engineering talk. The scientists assumed, but did not demonstrate in this paper,2 that natural selection was up to the task of yielding this optimized entity sometimes called the most complex assemblage of matter in the known universe.
Brains are mathematically perfect for achieving the sweet spot between maximized interconnectivity and minimized transmission delays. The authors reminded us that a human brain contains about 10 billion neurons, and that each one can contain thousands of connections with other neurons. The two-layer structure meets the competing requirements to a T. That part is amazing. Assuming that evolution did it earns this entry the Dumb award – really dumb.
Here again we are told about another apparition of the goddess of the Darwin Party, Tinker Bell. As the legend goes, she flitted aimlessly around the Cambrian swamps about 500 million years ago, zapping some emerging vertebrates with her mutation wand, killing countless myriads of them till one emerged lucky enough to have the beginnings of an optimized brain. As animals evolved, this process was repeated myriads of times more over millions of years, producing larger and more complex brains. Finally, at the end of the line, computational biologists emerged who could look back and analyze the whole process with abstract reasoning and mathematical equations, concluding that evolution had produced an optimized brain. Let us ask these true believers a simple question. If the brain evolved, how can you be sure of anything, including the proposition that the brain evolved? (From experience, we know that posing this type of question to a Darwinist is like putting a moron in a round room and telling him there is a penny in the corner.)
By assuming evolution at the outset, these computational evolutionists have provided as much insight into the origin of the brain as the vain mathematician did in the “assume we have a can opener” joke in the 12/17/2005 commentary. Their logic is as follows: Assume evolution produces optimized structures. An optimized brain would be structured so as to maximize interconnectivity and minimize delays. The brains we observe accomplish this by segregating highly-connected neurons in a gray matter layer and long axons in a white matter layer, thus fulfilling both requirements in an exquisite product that is the most complex device in the universe, that took us 62 simultaneous equations to describe. Isn’t evolution wonderful?
Undoubtedly this paper will be dutifully added to the growing corpus of scripture that the Darwin Party can hold up at school board meetings to show that the peer-reviewed scientific journals are filled with evidence for evolution, and that nothing in biology would make sense without it. Anyone raising his hand and saying, but to me, that looks like design would be quickly answered with, “Excuse me, we are talking about science here. If you want to change the subject to religion, go to church.”
Assumption is the mother of all myths. Perhaps you have heard the etymology of the word ASSUME: making an ASS (donkey) out of U and ME. Having gray matter is one thing. Using it is another.
Science is a trivial tool for understanding the universe.
You need to jump in your time machine and run back to 1859 to embarrass him out of publishing. It's too late now. We know the cell is complicated and we still see it as the product of evolution.
It's the only one that really teaches us anything that works.
You have been corrected on this lie numerous times. I myself have done so several dozen times, like here for example.
So my question is, are you fond of bearing false witness, or are you just unable to learn anything even after countless repetitions?
If you're just trolling because you have emotional problems, on the other hand, just say so, because I always make allowances for the handicapped.
Nonetheless, it beats the hell out of every other single method that's ever been tried, COMBINED.
It's already dead to God. Only He can regenerate the spirit.
For the record, the commentary in green fonts is provided by Creation-Evolution Headlines staff, not me.
I believe in evolution which is horizontal or descending in complexity. Supposed increases in complexity via RMNS, are actually horizontal evolution, rather than vertical. If there was substantial evidence of increases in complexity - as the evidence requires for RMNS to be a viable explanation for life as we see it today - then I would consider Darwinian Evolution as a vehicle for life to become more sophisticated.
Fortunately there is no evidence in the record, so my confidence in the Word of God is strengthened.
Speaking regarding Adam & Eve.
Mar 10:6 But from the beginning of the creation God made them male and female. (red letters indicate words spoken by the Christ in Christian)
Wow, are *YOU* confused about the topic you're lamely trying to critique... Here, learn something:
Introduction to Evolutionary Biology
ROFL!! Sorry, but your bizarre misunderstand about us is based on false presumptions.
Accepting the validity of evolutionary biology requires no "faith" at all, it requires familiarity with the evidence, understanding of the process involved, and knowledge, in the same way as it does not require "faith" to accept physics, chemistry, geology, etc.
Perhaps this essay will help you understand the difference: Do You Believe in Evolution?.
Or perhaps like most anti-evoluionists, you're so blinded by your fear that you don't *want* to understand.
Sigh. You're oversimplifying. There are lots of creatures with less intelligence than humans, and they do just fine........grey_whiskers
A creature's brain does not have to be intelligent in order to survive quite well in its particular environmental niche.
A case in point is Ted Kennedy in the Massachusetts Democrat environmental niche.
I believe in eternity, therefore I am not playing a game. I also don't want to bring my filth, or anyone else's, into eternity with us. Imagine having to deal with the perversions of this world for everlasting.
Isa 57:15 For thus saith the high and lofty One that inhabiteth eternity, whose name [is] Holy; I dwell in the high and holy [place],
Science is entertaining and sometimes helpful!
Do you ever get callouses? Why don't you have them all the time? Are the genetics for callous production in the junk DNA regions?
We know and understand less than 1% of our reality.
Yup. But when you posted earlier you suffered a "premature encapsulation" of the subject :-)
I think you're mistaking the issue here, or I was. It shouldn't be whether intelligence works. Anyway, most or all vertebrates have the brain architecture herein depicted, so it isn't about human levels of intelligence.
I think the question the article was trying to raise--and in my opinion they didn't do more than hint--was whether the observed degree of complexity in the human cortex was likely to result from the limited number of "experimental trials" or the relatively small amount of time elapsed.
(I.e. you get many more generations, and many more members of each generation, with viruses. That's why say, cold viruses, or AIDS, can have different antigenic signatures within a single host.) But do humans breed fast enough for all this structure to have emerged so quickly?
Some of the questions in my mind would be the following:
1. What is the amount of separation / intermingling between grey (!) and white matter in other primates compared to humans?
2. Do we have a good sense of the relation between "intelligence" (as if we could define that! ;-0 ) and the details of aforementioned cerebral wiring? Ditto for the exact genetic instructions for the mapping?
3. Is there any specific information on the environmental changes which would so drastically favor intellectual development of any nascent sapiens, but not wipe out the dumber cousins wholesale?
Cheers!
Thanks for the ping!
You "believe" incorrectly.
Supposed increases in complexity via RMNS, are actually horizontal evolution, rather than vertical.
Why, because you stamp your feet and insist that's true? It's not. And if you made the mistake of falling for Spetner's twaddle, he's a crank and he's wrong. Hell, even if he had been *right* his conclusion was rashly made on the basis of only *two* examples of *one* type of acquired resistance to antibiotics, and he would have been *insane* to generalize to *ALL* mutational adaptations based on just *two* (2) examples. But he did! And the creationists are just as nuts for swallowing that kind of idiocy whole (because they *want* to believe it), despite the fact that they'd rightly reject out of hand any *pro*evolution "study" if it was based on something that transparently bogus. Of course, at the same time, they hypocritically refuse to accept *any* research finding, no matter *how* well established and cross-validated, if it supports evolution (as every well-conducted study in the past 100+ years has done..)
Do you guys even believe the silly stuff that comes out of your own mouths?
If there was substantial evidence of increases in complexity - as the evidence requires for RMNS to be a viable explanation for life as we see it today - then I would consider Darwinian Evolution as a vehicle for life to become more sophisticated.
Then I'm happy to oblige:
Apolipoprotein AI Mutations and InformationI now await you usual lame excuses for why "that doesn't count", just as you and your ilk are cheerfully able to ignore *ALL* the overwhelming evidence for evolution.Creationist Claim CB102: Mutations are random noise; they do not add information.
Evolution of biological information
Evolution of biological complexity
Evolution and Information: The Nylon Bug
Examples of Beneficial Mutations and Natural Selection
Gene duplications in evolution of archaeal family B DNA polymerases
Koch, AL: Evolution of antibiotic resistance gene function. Microbiol Rev 1981, 45:355378.
Selection in the evolution of gene duplications
Velkov, VV: Gene amplification in prokaryotic and eukaryotic systems. Genetika 1982, 18:529543.
Romero, D & Palacios, R: Gene amplification and genomic plasticity in prokaryotes. Annu Rev Genet 1997, 31:91111.
Stark, GR & Wahl, GM: Gene amplification. Annu Rev Biochem 1984, 53:447491.
Reinbothe, S, Ortel, B, & Parthier, B: Overproduction by gene amplification of the multifunctional arom protein confers glyphosate tolerance to a plastid-free mutant of Euglena gracilis. Mol Gen Genet 1993, 239:416424.
Gottesman, MM, Hrycyna, CA, Schoenlein, PV, Germann, UA, & Pastan, I: Genetic analysis of the multidrug transporter. Annu Rev Genet 1995, 29:607649.
Schwab, M: Oncogene amplification in solid tumors. Semin Cancer Biol 1999, 9:319325.
Widholm, JM, Chinnala, AR, Ryu, JH, Song, HS, Eggett, T, & Brotherton, JE: Glyphosate selection of gene amplification in suspension cultures of three plant species. Physiol Plant 2001, 112:540545.
Otto, E, Young, JE, & Maroni, G: Structure and expression of a tandem duplication of the Drosophila metallothionein gene. Proc Natl Acad Sci USA 1986, 83:60256029.
Maroni, G, Wise, J, Young, JE, & Otto, E: Metallothionein gene duplications and metal tolerance in natural populations of Drosophila melanogaster. Genetics 1987, 117:739744.
Kondratyeva, TF, Muntyan, LN, & Karvaiko, GI: Zinc-resistant and arsenic-resistant strains of Thiobacillus ferrooxidans have increased copy numbers of chromosomal resistance genes. Microbiology 1995, 141:11571162.
Tohoyama, H, Shiraishi, E, Amano, S, Inouhe, M, Joho, M, & Murayama, T: Amplification of a gene for metallothionein by tandem repeat in a strain of cadmium-resistant yeast cells. FEMS Microbiol Lett 1996, 136:269273.
Sonti, RV & Roth, JR: Role of gene duplications in the adaptation of Salmonella typhimurium to growth on limiting carbon sources. Genetics 1989, 123:1928.
Brown, CJ, Todd, KM, & Rosenzweig, RF: Multiple duplications of yeast hexose transport genes in response to selection in a glucose-limited environment. Mol Biol Evol 1998, 15:931942.
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Lenormand, T, Guillemaud, T, Bourguet, D, & Raymond, M: Appearance and sweep of a gene duplication: adaptive response and potential for new functions in the mosquito Culex pipiens. Evolution 1998, 52:17051712.
Guillemaud, T, Raymond, M, Tsagkarakou, A, Bernard, C, Rochard, P, & Pasteur, N: Quantitative variation and selection of esterase gene amplification in Culex pipiens. Heredity 1999, 83:8799.
Fortunately there is no evidence in the record,
You know, if you had spent as much time actually reading science journals as you do desperately searching creatonist blogs looking for something to reinforce what you'd like to believe, you'd have qualified for an advanced degree by now.
Speak for *yourself*, please.
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