The Making of the Mind: The Neuroscience of Human Nature (33 page)

THE MENTAL ORGAN OF WRITING

Prehistoric artists drew images and carved bone to represent objects and events witnessed in their environment. These drawings symbolically represented real, concrete things, but they did so in a literal or iconographic manner. The graphic symbol was directly related to the icon or image remembered in the mind of the prehistoric artist. Examples of such iconographic representations are abundant from tens of thousands of years ago, but only much more recently did human beings invent less literal symbols. Only much later did human beings begin to use symbols to refer to abstract ideas that could not be easily conveyed through pictures. Nearly thirty-five thousand years passed between the first appearance of representational art in bone engravings and ivory carvings and the invention of writing.

The origins of writing can be traced back to around 3200 BCE in Mesopotamia, in the region of modern day Iraq.
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This writing system evolved gradually over a period of four thousand years from a system of tokens used by Neolithic farmers to keep track of food commodities, such as quantities of cereals. From these beginnings as a means of accounting, writing culturally evolved into an alternative mode of visible language and a powerful means of storing thought outside of the human brain. The innovation by the Greeks of the alphabetic writing we use today did not occur until around 750 BCE.
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The Greek alphabet was phonetic, making it possible to represent spoken language in a precise way with a minimal load on memory. With a couple dozen symbols, all the possible morphemes could be represented. Reading could thus become learned more readily, and the foundation for literate cultures was thus laid.

Although it would take centuries for literacy to penetrate the vast majority of the world's population, the cultural innovation of writing had an unmistakable effect on human mental functioning. The invention of writing was perhaps inevitable, given the brain's capacity for symbolic thought and oral language, and the executive capacity for innovation in social domains. Writing, then, like morality and spirituality, emerged from the modern ensemble mind of humans.

The invention of writing and the spread of literacy fed back to alter brain
functioning, the mind, and the societies in which we live in profound ways. As a consequence of cultural learning—through imitation and as a result of direct instruction—brain circuits are developed for decoding the symbols of written texts. Becoming a fluent reader entails training neural networks in the brain to recognize and comprehend the meaning of letters, words, phrases, sentences, and larger units of text structure. As with any visual stimulus, a word is first processed by the primary visual cortex in the occipital lobe at the rear of the brain. However, drawing on the existing specialization of the left hemisphere for language, a region just outside the primary visual cortex is activated by words in the left hemisphere—the fusiform gyrus, known as the word form area.
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If presented with strings of letter that either are words (ANT) or could be words (GEEL), the word form area is more strongly activated than by letter strings that are nonsensical and not word like (TBBL). The brain seems to use an area that is commonly used in processing other kinds of visual stimuli that call for chunking together features and integrating them into a whole. Because the letters can be chunked into the whole of a word, this fusiform area of the left hemisphere becomes part of the mental organ for processing words as a person learns how to read.

The extent to which the brain builds on its existing networks for oral language to cope with the cultural innovation of writing is evident from the following fact. A child's ability to discriminate among the basic building blocks of oral language is an excellent predictor of the ease with which reading is learned.
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Phoneme discrimination—a skill found in newborns because the brain is genetically prepared to tell one phoneme from another even in a foreign language not heard in the womb—is critical for later learning to the read the graphemes of written language. Between six and ten months, the sound distinctions that do not matter in the child's native language are lost as the phonological regions of the brain become attuned to the right phonemes for their oral language environment. There is a region in the left posterior part of the brain near the visual word form area that recodes the visual letters into the sounds of language. A second area of phonological processing is in the anterior region of the left hemisphere overlapping with Broca's area, which handles the articulation of sounds. This is the part of the brain involved in the phonological loop of verbal working memory and the inner voice of the interpreter.

As a third example of how reading uses the existing neural networks for oral language, a region just anterior to Broca's area in the left frontal cortex is activated when people pay attention to the meaning of a word.
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Attending to the semantic interpretation of a word (e.g., hammer) occurs when, for example, one must think of a verb that describes a use for the object (e.g., pound). Neuroimages of the brain as people perform this usage test show activation in this frontal semantic area regardless of whether the word is heard or read.

The brain becomes an organ of civilization, as Luria called it, by adapting to the learning experiences of a literate upbringing. Studies of numeracy also conform to this principle. In a simple test of how the brain processes numbers, participants are asked to decide if a number is greater than or less than five. The numbers are presented visually either as Arabic digits (4) or as a spelled word (four). The spelled word activates the visual word form area in the left hemisphere because reading is involved in the task. Strikingly, the visual presentation of Arabic digits is processed very differently.
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The activation is bilateral in the occipital and temporal lobes. The digits are a different kind of symbol from letters in that only digits draw upon the visual cortex as if they were pictures, making use of both hemispheres. The visual analysis is followed about forty milliseconds later by activation of both the left and right parietal lobes. It is here that the actual task of comparing the presented digit with the standard is carried out, followed by the decision that four or 4 is indeed less than five. The brain seems to represent a number line in the lower or inferior zone of the parietal lobe that allows an approximate judgment of magnitude.
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This area of the brain is already specialized for the processing of spatial locations, so a number-line representation fits well with its more general purpose. When number comparisons are done using dot patterns rather than Arabic digits, brain-wave patterns look the same for both the perceptual and symbolic representations of numbers.

Prior to the invention of writing in any form, for tens of thousands of years, modern human beings thought and communicated entirely through spoken language. The thoughts of oral language take the form of a narrative or story. A narrative contains a beginning, a middle, and an end; it pits a protagonist against an antagonist; it follows a plot as the events of the story unfold. Such a structure is an apt way to convey foundational truths and beliefs about
the world. For example, the fairy tales of Western culture are narratives about the basic issues of life: good versus evil, love versus hate, life versus death. All human cultures express their beliefs about the world through the medium of such shared communal stories. Consider the following:

A gathering of modern postindustrial Westerners around the family table, exchanging anecdotes and accounts of recent events, does not look much different from a similar gathering in a Stone age setting. Talk flows freely, almost entirely in the narrative mode. Stories are told and disputed; and a collective version of recent events is gradually hammered out as the meal progresses.
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The interpreter of consciousness provides the fundamental cognitive machinery for storytelling. The inner voice explains the events in terms of their causes and consequences, and a narrative structure is imposed on the experience. It is this narrative structure that becomes the foundation of oral culture. The inner story is shared with others in the group, and such stories can be retold and passed from one generation to the next. Narrative thought, however, is distinctly different from the logical thought that human beings are also capable of employing. As Jerome Bruner observed, “A good story and a well-formed argument are different natural kinds…and the structure of a well-formed logical argument differs radically from a well-wrought story.”
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Instead of thought proceeding in the form of a narrative, the alternative logical variety of thought proceeds from a premise to a conclusion or from specific data to a generalization. This kind of deductive and inductive thought is referred to as paradigmatic, analytic, or logicoscientific, and it owes much to the invention of writing.
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A new mental organ arose from the innovations of civilization itself. Logicoscientific thought draws upon the external memory storage afforded by pictures, graphs, and writing. It depends upon the availability of knowledge stored outside the individual brain and mind in external symbolic stores. Working memory is not overwhelmed with simply retrieving the events of the past that form the grist of narrative thought. Instead, with the aid of external memory storage, it is free to think, to deduce conclusions and induce generalizations. Logical reasoning and analytic thought are different from the storytelling of oral culture, and they form the foundation of the theoretical
culture of modern science. Again, it is not that narrative thought and oral culture have disappeared; rather, they have come to be accompanied by analytical thought and theoretical culture. Merlin Donald framed it this way: “In modern culture, narrative thought is dominant in the literary arts, while analytic thought predominates in science, law, and government.”
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Consider: (1) formal arguments such as deductive reasoning from a syllogism proceeding from a major premise to a minor premise to a necessary conclusion; (2) systematic taxonomies that are common in the sciences; (3) operational definitions of theoretical concepts; and (4) formal methods of measurement. These are ways of thinking that require analysis rather than narrative. They function to produce logical and empirical truth rather than historical accounts or stories. In science, the end product is a theory that can integrate ideas and arguments. A successful theory does not only explain past events within its purview; it can also predict future events.
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In the contemporary practice of law, one can also see the strong dependence of analytic thought on the external memory afforded by written texts. Case law is argued by citing the legal reasoning of past cases. Constitutional law similarly requires reference to the reasoning laid out in previous decisions of the courts. It is difficult, if not impossible, to imagine how legal scholars could proceed were it not for the ability to store the facts and arguments of previous cases in external forms of memory. The writing of opinions—the advancement of legal scholarship—depends on reading the texts of the past. Literacy lies at its heart.

The external storage of pictures and written language permits one to reflect on facts and analyze their relationships in ways that the storytelling of oral language does not. Seeing the connections among ideas is aided by having them represented in a visual-spatial form in which they can be examined, moved around, and linked. This is difficult to do when ideas must be held solely in working memory as the transient sounds of oral language. An external representation of a problem permits one to contemplate and evaluate possible solutions more readily than when everything must be held mentally in one's head. Imagine, for example, playing chess blindfolded, such that with each move the position of one's pieces plus the opponents pieces must be held and updated in working memory. This would readily overload even a strong
player's ability to entertain and evaluate alternative moves and anticipate the opponent's response. Only a master player, with an ability to retain the board's positions in well-learned chunks, is capable of playing without the external storage of a visible board. Thus, writing and analytical thought were symbiotic. With writing the modern human mind invented an external form of memory for the symbols of language. With it as a cognitive tool, “the human mind began to reflect upon the contents of its own representations, to modify and refine them.”
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Importantly, the invention of writing and the development of analytical thought could not have occurred but for the ensemble of the modern human mind. Composing a written text requires planning ideas, expressing them in sentences, and reviewing ideas and the text already produced. The process of composing a text that modifies what one thinks about a topic requires advanced working memory, in particular, strong executive-attention skills. To use writing as a vehicle for thinking and expanding one's knowledge, one must simultaneously hold in mind what the author wants to say and an awareness of what the text actually says. There is a back and forth interaction between trying to say something in text and then seeing if it makes sense to the author. The author then can rethink the ideas and modify the text accordingly. By reviewing the text to ascertain whether it really reflects the author's thoughts, it becomes possible to think through the act of composing. Until a child acquires the maturation of the prefrontal cortex and develops sufficient executive attention, this juggling act of planning, sentence generating, and reviewing is not possible. Rather, text composition proceeds in the form of thinking about an idea, then putting it in a sentence, and then thinking of another idea. There is little to no interplay between the text as written and the writer's original ideas.
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