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A Little Protein and a Big Bang

This blog is motivated in part by my conviction that life itself is far more mysterious than we are yet able to ponder.  And it is mathematics that has often redirected my attention back to that mystery as its wealth of conceptual possibilities shows me more of what we don’t understand.  David Deutsch very nicely articulated the source of my own perplexity at a TED conference in 2005.  Near the end of his talk he made the following remarks regarding human structure and universal structure or our physical system and the physical system of which we are a part.

The one physical system, the brain, contains an accurate working model of the other not just a superficial image of it (though it contains that as well) but an explanatory model embodying the same mathematical relationships and the same causal structure.

The faithfulness with which the one structure resembles the other is increasing with time

Its structure contains, with ever-increasing precision, the structure of everything.

 

This was brought back to me today when I read an October Discover article by Carl Zimmer.

The article reviews recent work investigating the FOXP2 gene, a gene that appears to be related to the development of language in our species and hence has been dubbed the language gene.

Modern ideas about our cultural evolution can be pragmatic and dull – the purpose of language is communication, communication enhances survival prospects, life is directed by survival needs.  In fact, the single most frequent complaint I hear from students in required math classes is “But when will I ever need this?”

Alternatively, a candid look at investigations of the language gene suggests that small, apparently random changes work within themselves to offer new expressions of life itself. Zimmer explains that this language gene produces a protein that seems especially active when human embryos are developing.  It switches on in neurons within particular regions of the brain and then latches onto other genes in developing neurons and switches them on or off as well.   And so it has the quality of being able to regulate the activity of other genes.

Humans are not the only species to benefit from FOXP2. Researchers have shown that the gene is associated with vocal learning in young songbirds, which produce higher levels of FOXP2 protein when they need to learn new songs. If their version of FOXP2 is impaired, they make singing mistakes. Other vocal-learning species, such as whales, bats, elephants, and seals, may also rely on the gene.

These findings hint at what happened to FOXP2 in our ancestors. It may have started out hundreds of millions of years ago as a gene that helped regulate the learning of body movements, such as those involved in running, calling, and biting. Later mutations in the gene spurred more neural growth in certain areas of the brain, including the basal ganglia, creating the connections essential for learning and mastering complicated sounds and, eventually, full-blown language.

FOXP2 didn’t give us language all on its own. In our brains, it acts more like a foreman, handing out instructions to at least 84 target genes in the developing basal ganglia. Even this full crew of genes explains language only in part, because the ability to form words is just the beginning. Then comes the higher level of complexity: combining words according to rules of grammar to give them meaning.

There is reason to believe that mirror neurons, those motor neurons that are activated when we are watching action as well as when we’re doing it, play a role in the development of language (there being a strong motor component to spoken language).  It’s interesting, however, that these neurons don’t mirror all action, but do mirror action that seems to be characterized by some intentionality.

It is the interactive nature of neurons that got my attention again.  The area of the brain more recently found to be important for language processing is located at the junction where auditory and visual sense data are processed as well as stimuli from the skin and internal organs.  And these neurons are multimodal, meaning that they can process different kinds of stimuli (auditory, visual, sensorimotor, etc.) This combination of traits makes this area (the inferior parietal lobule) ideal for grasping the different properties of spoken and written words: their sound, their appearance, their function, etc. It is also thought that this area may enable the brain to classify and label things, leading to the formation of concepts and thinking abstractly.

There’s a nice multi-level description of language with information about its social, psychological, neurological, cellular and molecular aspects on The Brain From Top to Bottom. The levels you can look through are on the top right of the page.

Mathematics is not the same as language, but its development has relied on the development of language.  And the great mystery reveals itself to me again when I see that David Deutsch’s observation rests on the action of a protein.

3 comments to A Little Protein and a Big Bang

  • happyseaurchin

    and feel free to cast that net wide
    because i think there is something to be said about patterns that exist across many apparently different areas
    self-similarity and all that

    i
    for one
    enjoy it 🙂

  • I agree about the words. I’ve become very much aware of this watching my 4-year old’s vocabulary expand. It’s all sound and gesture.

    I know it’s a big net, but I let myself do it this time.

  • happyseaurchin

    interesting
    rather broad net you cast 🙂

    just one comment the properties of spoken and written words:
    i believe we in the west have too much of an emphasis on the written word
    so much so
    that we think that we speak “words”
    wrt mirror neurons and intentionality etc
    we are dealing with something that is less to do with written
    and more to do with live speaking/listening processes