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Stanislaus Dehaene’s Reading in the Brain

Tradition has it that the first Chinese letters were inspired by a hoof print on a riverbank. The renowned Emperor Huangdi, who reigned some four and half thousand years ago, was unsatisfied with the information storage technology of the time, which consisted of knots tied in strings. He ordered his minister Cang Jie to devise a better system. But no solution came to Cang Jie until one day, wandering in despair, he came on a busy pattern of hoof prints in mud by a river. He could read the whole array except for one set of prints, which belonged to an animal he’d never seen. And this was his moment of insight: animal tracks, he realized, were easily distinguishable and could be reproduced in meaningful patterns. And they could stand in for things no one had ever seen, not just unknown animals, but anything imaginable.

In his 2009 book Reading in the Brain: the New Science of How We Read, Stanislaus Dehaene tells a much more complicated version of what is effectively the same story. Honored with the first chair of Experimental Cognitive Psychology at the Collège de France in 2005, Dehaene is best known for his popular, albeit demanding, summations of recent neuroscience, including The Number Sense in 1997 and, more recently and ambitiously, Consciousness and the Brain in 2014.

Like Cang Jie, we have to go through a bit of concentrated puzzlement before we find the animal tracks in Reading in the Brain. Dehaene only considers them as a possible inspiration for the invention of writing in the second half of his book. The prior two hundred and some pages are devoted to detailed descriptions of brain injuries, fMRIs, experimental “event-related potentials,” intracranial electrode readings, and analyses of the graphic principles underlying the world’s writing systems, all of which add up to a very intimate encounter with the complex physiological processes going on in your brain right now.

The crux of all the neuroscience is that human brains come equipped with an array of specialized neural “centers” for processing visual information of various kinds. These centers sort what William James famously called the “blooming, buzzing confusion” of the world into relatively stable ideas. Thus, for example, we know a friend’s face, apart from whatever expression she wears from one occasion to the next. By the same principle, we can spot tell-tale signs of anger, fear or joy on a stranger’s face without the slightest conscious effort. And we take these talents for “invariant pattern recognition” a step further when we teach ourselves, say, to spot a prothonotary warbler on the far bank of the Potomac, or identify what species of oak it’s sitting in. That is, we can assign fixed categories to the stable visual patterns we find in the world. In short, we develop knowledge, and pass it on through teaching so that it becomes like a second nature.

These basic human knacks – for recognizing invariant visual patterns and assigning a fixed significance to them – are the innate cognitive tools with which we built our systems for writing and reading. Like sensing emotion on a stranger’s face, we can see through extraordinary typographical variety to our letters’ underlying, invariant formal patterns. This lets us read words whether they’re scratched or chiseled, upper or lower case, Times or Comic Sans, or  jumbled deviously into a ransom note. The innovation of writing is to have created a stable pattern of visual marks to encode stable patterns of sounds in speech, making language available to the eye as well as the ear.

It’s crucial that, as opposed to language per se, we have a solid knowledge of the origins of writing. Reliable evidence of the historical origins of human language itself are probably all but lost to us. But evidence of the first writing systems is (comparatively) abundant, and date back to about the fifth century bce. After this date, writing systems seem to have begun appearing independently of each other among disparate cultures around the world. The historically recent and rapid development of writing systems around the world make it clear that humans can’t have evolved specifically to read. There has simply not been enough time for natural selection to have guided this momentous turn in human affairs by supplying us with an innate neural “reading center.”

So we have to account for this new skill by finding its evolutionary roots somewhere else in our brains’ large but still limited repertoire. Since our supply of neurons is ultimately finite, and the gross character of our brain’s various functional centers have already been set by evolutionary development, we must have borrowed or, in Dehaene’s terms, “recycled” some part or parts of the brain that had originally evolved to perform some other activity involving similarly complex visual sorting and categorization. So what was this now-relegated function?

Channeling Cang Jie, Dehaene surmises that it may well have been animal tracking, among other prehistoric skills. In sum, Dehaene proposes that our ability to develop and read a written language depended on trading in our ability to “read” complex combinations of signs in the mountains, forests, savannahs and deserts we had long wandered as hunter-gatherers. It is probably not a coincidence, he argues, that the world’s writing systems tend to be based on relatively simple and limited formal schema of the same kind that we see in animal tracks, vegetation, and other patterned phenomena in natural environments of which we had to have an intimate visual knowledge in order to survive.

So much for origins. Yet Dehaene does not simply look back in trying to understand how we read. He also wants to use the insights of the latest new science to venture “Toward a Culture of Neurons,” as he announces in the title of his last chapter. There, he sums up the larger argument of the book: that we must rethink the currently popular notion of the brain and, by extension, human culture, as highly malleable, “plastic” formations. He uses our reading brains as evidence of the essential constraints on what we can hope to achieve with the mental endowment we have inherited from millions of years of selective pressures of all kinds. The small number of formal variations in the elements of most writing systems are to Dehaene important evidence of the similarly well-defined and fixed brain structures that have shaped them. On his view, the innate patterning of our neurological equipment in general will favor a cultural environment that fits this evolutionary endowment, which necessarily constrains whatever hopes we may have for cultural innovation.

Thus, for example, he devotes a major portion of his book to unfolding recent research into phenomena like synesthesia and especially dyslexia, both of which put large numbers of new readers at odds with culturally-determined pedagogical practices. Based on his own and allied research, Dehaene makes a very persuasive case for how – and how not – to teach reading, including to the many children whose brains are structured in myriad ways differently than the predominating pattern. More generally, Dehaene argues that without the guidance we get from good brain research, we often follow misguided cultural imperatives that risk not making the most of our innate abilities, or confuse us unnecessarily and risk making us miserable.

There is thus much to recommend Dehaene’s work in the way of correctives to even well-meaning but misguided pedagogies (and the field of applications of new brain science is potentially much larger, of course). But Dehaene risks overreaching in his hopes for the new science of the brain. He has argued elsewhere that his work on the reading brain vindicates the now much-contested “structuralist” theory of culture associated most closely with the work of anthropologist Claude Levi-Strauss. Briefly, on the structuralist view, there is an underlying but discernable pattern of binary categories that orient every distinct culture’s responses to universal aspects of human experience (death, for example, or birth, or kinship). Dehaene supposes that within such cultural categories, or “structures,” lie “specific brain systems” of the kind he has described in the case not only of reading, but before that of math, and now of consciousness itself.

In fact, in his most recent book, Dehaene takes his structuralism a step further by addressing himself directly to the challenge posed by philosopher David Chalmers as the so-called “hard problem of consciousness.” For Chalmers, the “easy” questions about consciousness can be answered by the means Dehaene so adeptly deploys: experimental cognitive psychology and brain imaging. Experimentation leads inevitably to a functional understanding of how the brain performs tasks such as telling one thing from another, or focusing attention on a particular subject, or recognizing patterns on a computer screen as words. But the firmest grasp of the brain’s functioning can never, Chalmers argues, explain in turn our unique conscious feelings of, say, a color, or a taste, or an especially satisfying passage of prose or poetry.

Dehaene differs fundamentally, arguing that Chalmers has the problems reversed. What Chalmers considers easy problems, Dehaene asserts are the hard ones – with his career as an experimenalist to back him up. Chalmers’ hard problem, on the other hand, Dehaene thinks will turn out not to have been a problem at all, but the long-cherished illusion of an interior realm of self-awareness we will no longer be able to maintain once we’ve sufficiently understood how the brain works.

I won’t presume to adjudicate between Dehaene and Chalmers here. I relate Dehaene’s account of consciousness to indicate how deeply he holds to the idea that the brain contains within itself a sufficient map of virtually every aspect of human existence. His interest in Levi-Straussian structuralism is thus clear, but also telling in how little it affords a guide to developing “a culture” of neurons, or of anything else, at that. Structuralist anthropology proceeds by way of comparisons between specific cultures in order to arrive at rubrics within which any given culture can be situated for further comparative analysis. The chief critiques of structuralism that have emerged over the last fifty to sixty-odd years have focused on the fact that while the formal patterns found in language, writing, ritual or myth may appear relatively fixed, their significance – what they mean to different people at different times – inevitably shifts. Understanding the brain may well help us design better schools and help more children to read, but their ability to read has no – and can’t have – any bearing on how children understand what they read. A function, in short, is not a purpose, and there is literally no telling what a human mind might devise given even the most rigidly defined set of capabilities.

 

In this light, the graphic limits that Dehaene adduces within the world’s alphabets are beautiful examples of the vast generative possibilities of structural constraint. Rendering the greater complexities of spoken language into stricter  formal patterns of writing systems (such as our alphabet) in fact open up the cumulative possibilities of enduring writing and reading that have given us, among other things, the vast intertextual complexity of the world’s imaginative literature. And this literature is our ever-growing storehouse of forms of consciousness that we preserve from the past and communicate into whatever future awaits us, but that we will be helpless to keep shaping without writing.

But if Dehaene seems to mistake the tool for the variety of ends it makes possible, he at least hints at the possibility that a culture represents more than the operations of brain cells. While his envoi gestures “toward a culture of neurons,” he opens by quoting Francisco de Quevedo, the venerable Spanish Baroque man of letters for whom to read was “to listen to the dead with [his] eyes.” Quevedo’s image is surely one of the most striking and most widely quoted descriptions of reading ever devised. But pinning down just how this or any other tolerably successful metaphor makes meaning turns out to be a notoriously difficult problem. Quevedo’s (so far as I know, unique) description of reading makes immediate and eminent metaphorical sense, even as the common meanings of his words add up to perfect nonsense. Such tension between sense and nonsense is a hallmark of good metaphors: they play simultaneously into and against our conventional understandings; they make startling, even risky leaps into the realm of meaning and thrill us when they stick the landing. In terms of the structures that govern language and its normal, everyday functions, metaphors simultaneously rely on and defy them.

Perhaps not surprisingly, metaphor turns up as one of the central functions in Dehaene’s own culture of neurons, i.e. his own playful attempt to jostle us out of our current thinking by juxtaposing ideas we thought we understood. He remarks that the basic human ability to make metaphors appears to have been crucial in the invention of writing itself. Having stripped our environment down into recognizable, reliable signs, we then made the extra and decisive leap of stripping those signs of their naturally given associations in order to assign them to whatever phenomena we pleased, no matter how abstract. This is the leap of metaphor, the mapping of one disparate idea onto another, which Dehaene locates in the human brain’s limitless ability to create new associations between its functional centers. Though the brain’s functions are indeed limited in kind and number, like the letters of the alphabet they can be endlessly recombined into new ideas and, by extension, new human activities. If animal tracking and reading do share neurons, it’s only good evidence that we may have other epochal inventions in store for ourselves. Our invention of writing alone has offered such elaborate means for manipulating our experience through symbols that the possible permutations of human experience appear effectively limitless.

With his closing paean to metaphor, Deheane calls Friedrich Nietzsche to this reader’s mind (though probably without meaning to). A “post-structuralist” a good century avant-la-lettre, Nietzsche proposed philosophical problems that shaped many of the most trenchant critiques of Levi-Strauss’ anthropological project a hundred years later. One of Nietzsche’s most important statements regarding universal human structures comes in a short early essay “On Truth and Lie in an Extra-Moral Sense.” In an argument reminiscent of Dehaene’s, Nietzsche finds the foundation of language in the the arbitrary association of sensations with sounds, a metaphorical procedure. But Nietzsche’s primary concern is how this process of verbalizing our experience leads to truths, which turn out to be simply metaphors whose origins we have forgotten in adhering to them through habit, without reflection – including by putting them into writing. Such old, venerated metaphors only appear to be decisive, unarguable statements about the world at large exactly because we have since forgotten that they began by recording our all-too-human sensations. Nietzsche calls on us to show the philosophical acumen and moral courage necessary to reveal the metaphors within our truths, and thereby open them back up to further elaboration. Alternatively, we can also seek to replace outworn “truths” with radically new metaphors: new descriptions of experience, new forms of life – in short, with whole new cultural formations. Similarly, what Dehaene in fact provides in this book is a very close and compelling look not just at how we are structured but at how the constraints within the stuctures he describes can add up to a subtle but powerful freedom.

Dehaene, Stanislaus. Reading in the Brain: the new science of how we read. Penguin Books. 2009

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