The Shallows: What the Internet Is Doing to Our Brains

by Nicholas Carr

What both enthusiast and skeptic miss is what McLuhan saw: that in the long run a medium’s content matters less than the medium itself in influencing how we think and act. As our window onto the world, and onto ourselves, a popular medium molds what we see and how we see it—and eventually, if we use it enough, it changes who we are, as individuals and as a society. “The effects of technology do not occur at the level of opinions or concepts,” wrote McLuhan. Rather, they alter “patterns of perception steadily and without any resistance.”3 The showman exaggerates to make his point, but the point stands. Media work their magic, or their mischief, on the nervous system itself. Our focus on a medium’s content can blind us to these deep effects. We’re too busy being dazzled or disturbed by the programming to notice what’s going on inside our heads. In the end, we come to pretend that the technology itself doesn’t matter. It’s how we use it that matters, we tell ourselves. The implication, comforting in its hubris, is that we’re in control. The technology is just a tool, inert until we pick it up and inert again once we set it aside.

Point 1

McLuhan scoffed at the idea, chiding Sarnoff for speaking with “the voice of the current somnambulism.”4 Every new medium, McLuhan understood, changes us. “Our conventional response to all media, namely that it is how they are used that counts, is the numb stance of the technological idiot,” he wrote. The content of a medium is just “the juicy piece of meat carried by the burglar to distract the watchdog of the mind.”5

Point 2 McLuhan responding to David Sarnoff, who said that it is not the technology but how we use it that matters.

As McLuhan suggested, media aren’t just channels of information. They supply the stuff of thought, but they also shape the process of thought. And what the Net seems to be doing is chipping away my capacity for concentration and contemplation. Whether I’m online or not, my mind now expects to take in information the way the Net distributes it: in a swiftly moving stream of particles. Once I was a scuba diver in the sea of words. Now I zip along the surface like a guy on a Jet Ski.

Point 3

We seem to have arrived, as McLuhan said we would, at an important juncture in our intellectual and cultural history, a moment of transition between two very different modes of thinking. What we’re trading away in return for the riches of the Net—and only a curmudgeon would refuse to see the riches—is what Karp calls “our old linear thought process.” Calm, focused, undistracted, the linear mind is being pushed aside by a new kind of mind that wants and needs to take in and dole out information in short, disjointed, often overlapping bursts—the faster, the better. John Battelle, a onetime magazine editor and journalism professor who now runs an online advertising syndicate, has described the intellectual frisson he experiences when skittering across Web pages: “When I am performing bricolage in real time over the course of hours, I am ‘feeling’ my brain light up, I [am] ‘feeling’ like I’m getting smarter.”11 Most of us have experienced similar sensations while online. The feelings are intoxicating—so much so that they can distract us from the Net’s deeper cognitive consequences.

Point 4

The computer, I began to sense, was more than just a simple tool that did what you told it to do. It was a machine that, in subtle but unmistakable ways, exerted an influence over you. The more I used it, the more it altered the way I worked. At first I had found it impossible to edit anything on-screen. I’d print out a document, mark it up with a pencil, and type the revisions back into the digital version. Then I’d print it out again and take another pass with the pencil. Sometimes I’d go through the cycle a dozen times a day. But at some point—and abruptly—my editing routine changed. I found I could no longer write or revise anything on paper. I felt lost without the Delete key, the scrollbar, the cut and paste functions, the Undo command. I had to do all my editing on-screen. In using the word processor, I had become something of a word processor myself.

Sometime in 2007, a serpent of doubt slithered into my info-paradise. I began to notice that the Net was exerting a much stronger and broader influence over me than my old stand-alone PC ever had. It wasn’t just that I was spending so much time staring into a computer screen. It wasn’t just that so many of my habits and routines were changing as I became more accustomed to and dependent on the sites and services of the Net. The very way my brain worked seemed to be changing. It was then that I began worrying about my inability to pay attention to one thing for more than a couple of minutes. At first I’d figured that the problem was a symptom of middle-age mind rot. But my brain, I realized, wasn’t just drifting. It was hungry. It was demanding to be fed the way the Net fed it—and the more it was fed, the hungrier it became. Even when I was away from my computer, I yearned to check e-mail, click links, do some Googling. I wanted to be connected. Just as Microsoft Word had turned me into a flesh-and-blood word processor, the Internet, I sensed, was turning me into something like a high-speed data-processing machine, a human HAL. I missed my old brain.

In March, a Berlin newspaper reported that Nietzsche “feels better than ever” and, thanks to his typewriter, “has resumed his writing activities.” But the device had a subtler effect on his work. One of Nietzsche’s closest friends, the writer and composer Heinrich Köselitz, noticed a change in the style of his writing. Nietzsche’s prose had become tighter, more telegraphic. There was a new forcefulness to it, too, as though the machine’s power—its “iron”—was, through some mysterious metaphysical mechanism, being transferred into the words it pressed into the page. “Perhaps you will through this instrument even take to a new idiom,” Köselitz wrote in a letter, noting that, in his own work, “my ‘thoughts’ in music and language often depend on the quality of pen and paper.” “You are right,” Nietzsche replied. “Our writing equipment takes part in the forming of our thoughts.”2

One of the simplest yet most powerful demonstrations of how synaptic connections change came in a series of experiments that the biologist Eric Kandel performed in the early 1970s on a type of large sea slug called Aplysia. (Sea creatures make particularly good subjects for neurological tests because they tend to have simple nervous systems and large nerve cells.) Kandel, who would earn a Nobel Prize for his work, found that if you touch a slug’s gill, even very lightly, the gill will immediately and reflexively recoil. But if you touch the gill repeatedly, without causing any harm to the animal, the recoiling instinct will steadily diminish. The slug will become habituated to the touch and learn to ignore it. By monitoring slugs’ nervous systems, Kandel discovered that “this learned change in behavior was paralleled by a progressive weakening of the synaptic connections” between the sensory neurons that “feel” the touch and the motor neurons that tell the gill to retract. In a slug’s ordinary state, about ninety percent of the sensory neurons in its gill have connections to motor neurons. But after its gill is touched just forty times, only ten percent of the sensory cells maintain links to the motor cells. The research “showed dramatically,” Kandel wrote, that “synapses can undergo large and enduring changes in strength after only a relatively small amount of training.”19

Now i have to read In search of Memory by Eric Kandel. It has been in Vivaldi (wink) for days.

Plastic does not mean elastic, in other words. Our neural loops don’t snap back to their former state the way a rubber band does; they hold onto their changed state. And nothing says the new state has to be a desirable one. Bad habits can be ingrained in our neurons as easily as good ones. Pascual-Leone observes that “plastic changes may not necessarily represent a behavioral gain for a given subject.” In addition to being “the mechanism for development and learning,” plasticity can be “a cause of pathology.”35 It comes as no surprise that neuroplasticity has been linked to mental afflictions ranging from depression to obsessive-compulsive disorder to tinnitus. The more a sufferer concentrates on his symptoms, the deeper those symptoms are etched into his neural circuits. In the worst cases, the mind essentially trains itself to be sick. Many addictions, too, are reinforced by the strengthening of plastic pathways in the brain. Even very small doses of addictive drugs can dramatically alter the flow of neurotransmitters in a person’s synapses, resulting in long-lasting alterations in brain circuitry and function. In some cases, the buildup of certain kinds of neurotransmitters, such as dopamine, a pleasure-producing cousin to adrenaline, seems to actually trigger the turning on or off of particular genes, bringing even stronger cravings for the drug. The vital paths turn deadly. The potential for unwelcome neuroplastic adaptations also exists in the everyday, normal functi...

Survival of the busiest

That doesn’t mean that we can’t, with concerted effort, once again redirect our neural signals and rebuild the skills we’ve lost. What it does mean is that the vital paths in our brains become, as Monsieur Dumont understood, the paths of least resistance. They are the paths that most of us will take most of the time, and the farther we proceed down them, the more difficult it becomes to turn back.

EVERY TECHNOLOGY IS an expression of human will. Through our tools, we seek to expand our power and control over our circumstances—over nature, over time and distance, over one another. Our technologies can be divided, roughly, into four categories, according to the way they supplement or amplify our native capacities. One set, which encompasses the plow, the darning needle, and the fighter jet, extends our physical strength, dexterity, or resilience. A second set, which includes the microscope, the amplifier, and the Geiger counter, extends the range or sensitivity of our senses. A third group, spanning such technologies as the reservoir, the birth control pill, and the genetically modified corn plant, enables us to reshape nature to better serve our needs or desires. The map and the clock belong to the fourth category, which might best be called, to borrow a term used in slightly different senses by the social anthropologist Jack Goody and the sociologist Daniel Bell, “intellectual technologies.” These include all the tools we use to extend or support our mental powers—to find and classify information, to formulate and articulate ideas, to share know-how and knowledge, to take measurements and perform calculations, to expand the capacity of our memory. The typewriter is an intellectual technology. So are the abacus and the slide rule, the sextant and the globe, the book and the newspaper, the school and the library, the computer and the Internet. Although the use of any ...

Our ancestors didn’t develop or use maps in order to enhance their capacity for conceptual thinking or to bring the world’s hidden structures to light. Nor did they manufacture mechanical clocks to spur the adoption of a more scientific mode of thinking. Those were by-products of the technologies. But what by-products! Ultimately, it’s an invention’s intellectual ethic that has the most profound effect on us. The intellectual ethic is the message that a medium or other tool transmits into the minds and culture of its users.

Unforeseen effects?

Sometimes our tools do what we tell them to. Other times, we adapt ourselves to our tools’ requirements.

Today, at last, the mists that have obscured the interplay between technology and the mind are beginning to lift. The recent discoveries about neuroplasticity make the essence of the intellect more visible, its steps and boundaries easier to mark. They tell us that the tools man has used to support or extend his nervous system—all those technologies that through history have influenced how we find, store, and interpret information, how we direct our attention and engage our senses, how we remember and how we forget—have shaped the physical structure and workings of the human mind. Their use has strengthened some neural circuits and weakened others, reinforced certain mental traits while leaving others to fade away. Neuroplasticity provides the missing link to our understanding of how informational media and other intellectual technologies have exerted their influence over the development of civilization and helped to guide, at a biological level, the history of human consciousness.

Under the sway of the mechanical clock, people began thinking of their brains and their bodies—of the entire universe, in fact—as operating “like clockwork.” In the clock’s tightly interconnected gears, turning in accord with the laws of physics and forming a long and traceable chain of cause and effect, we found a mechanistic metaphor that seemed to explain the workings of all things, as well as the relations between them. God became the Great Clockmaker. His creation was no longer a mystery to be accepted. It was a puzzle to be worked out. Wrote Descartes in 1646, “Doubtless when the swallows come in spring, they operate like clocks.”17

Language itself is not a technology. It’s native to our species. Our brains and bodies have evolved to speak and to hear words. A child learns to talk without instruction, as a fledgling bird learns to fly. Because reading and writing have become so central to our identity and culture, it’s easy to assume that they, too, are innate talents. But they’re not. Reading and writing are unnatural acts, made possible by the purposeful development of the alphabet and many other technologies. Our minds have to be taught how to translate the symbolic characters we see into the language we understand. Reading and writing require schooling and practice, the deliberate shaping of the brain. Evidence of this shaping process can be seen in many neurological studies. Experiments have revealed that the brains of the literate differ from the brains of the illiterate in many ways—not only in how they understand language but in how they process visual signals, how they reason, and how they form memories.

As Tufts University developmental psychologist Maryanne Wolf explains in her book on the neuroscience of reading, Proust and the Squid, “Although all reading makes use of some portions of the frontal and temporal lobes for planning and for analyzing sounds and meanings in words, logographic systems appear to activate very distinctive parts of [those] areas, particularly regions involved in motoric memory skills.”20 Differences in brain activity have even been documented among readers of different alphabetic languages. Readers of English, for instance, have been found to draw more heavily on areas of the brain associated with deciphering visual shapes than do readers of Italian. The difference stems, it’s believed, from the fact that English words often look very different from the way they sound, whereas in Italian words tend to be spelled exactly as they’re spoken.21

The Sumerians and the Egyptians had to develop neural circuits that, according to Wolf, literally “crisscrossed” the cortex, linking areas involved not only in seeing and sense-making but in hearing, spatial analysis, and decision making.23 As these logosyllabic systems expanded to include many hundreds of characters, memorizing and interpreting them became so mentally taxing that their use was probably restricted to an intellectual elite blessed with a lot of time and brain power. For writing technology to progress beyond the Sumerian and Egyptian models, for it to become a tool used by the many rather than the few, it had to get a whole lot simpler.

Theuth describes the art of writing to Thamus and argues that the Egyptians should be allowed to share in its blessings. It will, he says, “make the people of Egypt wiser and improve their memories,” for it “provides a recipe for memory and wisdom.” Thamus disagrees. He reminds the god that an inventor is not the most reliable judge of the value of his invention: “O man full of arts, to one is it given to create the things of art, and to another to judge what measure of harm and of profit they have for those that shall employ them. And so it is that you, by reason of the tender regard for the writing that is your offspring, have declared the very opposite of its true effect.” Should the Egyptians learn to write, Thamus goes on, “it will implant forgetfulness in their souls: they will cease to exercise memory because they rely on that which is written, calling things to remembrance no longer from within themselves, but by means of external marks.” The written word is “a recipe not for memory, but for reminder. And it is no true wisdom that you offer your disciples, but only its semblance.” Those who rely on reading for their knowledge will “seem to know much, while for the most part they know nothing.” They will be “filled, not with wisdom, but with the conceit of wisdom.”

The oral world of our distant ancestors may well have had emotional and intuitive depths that we can no longer appreciate. McLuhan believed that preliterate peoples must have enjoyed a particularly intense “sensuous involvement” with the world. When we learned to read, he argued, we suffered a “considerable detachment from the feelings or emotional involvement that a nonliterate man or society would experience.”31 But intellectually, our ancestors’ oral culture was in many ways a shallower one than our own. The written word liberated knowledge from the bounds of individual memory and freed language from the rhythmical and formulaic structures required to support memorization and recitation. It opened to the mind broad new frontiers of thought and expression. “The achievements of the Western world, it is obvious, are testimony to the tremendous values of literacy,” McLuhan wrote.32 Ong, in his influential 1982 study Orality and Literacy, took a similar view. “Oral cultures,” he observed, could “produce powerful and beautiful verbal performances of high artistic and human worth, which are no longer even possible once writing has taken possession of the psyche.” But literacy “is absolutely necessary for the development not only of science but also of history, philosophy, explicative understanding of literature and of any art, and indeed for the explanation of language (including oral speech) itself.”33 The ability to write is “utterly invaluable and indeed essential for the r...

In the choices we have made, consciously or not, about how we use our computers, we have rejected the intellectual tradition of solitary, single-minded concentration, the ethic that the book bestowed on us. We have cast our lot with the juggler.

Dozens of studies by psychologists, neurobiologists, educators, and Web designers point to the same conclusion: when we go online, we enter an environment that promotes cursory reading, hurried and distracted thinking, and superficial learning. It’s possible to think deeply while surfing the Net, just as it’s possible to think shallowly while reading a book, but that’s not the type of thinking the technology encourages and rewards.

With the exception of alphabets and number systems, the Net may well be the single most powerful mind-altering technology that has ever come into general use. At the very least, it’s the most powerful that has come along since the book.

Our use of the Internet involves many paradoxes, but the one that promises to have the greatest long-term influence over how we think is this one: the Net seizes our attention only to scatter it. We focus intensively on the medium itself, on the flickering screen, but we’re distracted by the medium’s rapid-fire delivery of competing messages and stimuli. Whenever and wherever we log on, the Net pre-sents us with an incredibly seductive blur. Human beings “want more information, more impressions, and more complexity,” writes Torkel Klingberg, the Swedish neuroscientist. We tend to “seek out situations that demand concurrent performance or situations in which [we] are overwhelmed with information.”2 If the slow progression of words across printed pages dampened our craving to be inundated by mental stimulation, the Net indulges it. It returns us to our native state of bottom-up distractedness, while presenting us with far more distractions than our ancestors ever had to contend with.

In a 2005 interview, Michael Merzenich ruminated on the Internet’s power to cause not just modest alterations but fundamental changes in our mental makeup. Noting that “our brain is modified on a substantial scale, physically and functionally, each time we learn a new skill or develop a new ability,” he described the Net as the latest in a series of “modern cultural specializations” that “contemporary humans can spend millions of ‘practice’ events at [and that] the average human a thousand years ago had absolutely no exposure to.” He concluded that “our brains are massively remodeled by this exposure.”5 He returned to this theme in a post on his blog in 2008, resorting to capital letters to emphasize his points. “When culture drives changes in the ways that we engage our brains, it creates DIFFERENT brains,” he wrote, noting that our minds “strengthen specific heavily-exercised processes.” While acknowledging that it’s now hard to imagine living without the Internet and online tools like the Google search engine, he stressed that “THEIR HEAVY USE HAS NEUROLOGICAL CONSEQUENCES.”6 What we’re not doing when we’re online also has neurological consequences. Just as neurons that fire together wire together, neurons that don’t fire together don’t wire together. As the time we spend scanning Web pages crowds out the time we spend reading books, as the time we spend exchanging bite-sized text messages crowds out the time we spend composing sentences and paragraphs, as the time we s...

As the executive functions of the prefrontal cortex kick in, our brains become not only exercised but overtaxed. In a very real way, the Web returns us to the time of scriptura continua, when reading was a cognitively strenuous act. In reading online, Maryanne Wolf says, we sacrifice the facility that makes deep reading possible. We revert to being “mere decoders of information.”10

It was once assumed that long-term memory served merely as a big warehouse of facts, impressions, and events, that it “played little part in complex cognitive processes such as thinking and problem-solving.”14 But brain scientists have come to realize that long-term memory is actually the seat of understanding. It stores not just facts but complex concepts, or “schemas.” By organizing scattered bits of information into patterns of knowledge, schemas give depth and richness to our thinking. “Our intellectual prowess is derived largely from the schemas we have acquired over long periods of time,” says Sweller. “We are able to understand concepts in our areas of expertise because we have schemas associated with those concepts.”15 The depth of our intelligence hinges on our ability to transfer information from working memory to long-term memory and weave it into conceptual schemas.

Imagine filling a bathtub with a thimble; that’s the challenge involved in transferring information from working memory into long-term memory. By regulating the velocity and intensity of information flow, media exert a strong influence on this process. When we read a book, the information faucet provides a steady drip, which we can control by the pace of our reading. Through our single-minded concentration on the text, we can transfer all or most of the information, thimbleful by thimbleful, into long-term memory and forge the rich associations essential to the creation of schemas. With the Net, we face many information faucets, all going full blast. Our little thimble overflows as we rush from one faucet to the next. We’re able to transfer only a small portion of the information to long-term memory, and what we do transfer is a jumble of drops from different faucets, not a continuous, coherent stream from one source. The information flowing into our working memory at any given moment is called our “cognitive load.” When the load exceeds our mind’s ability to store and process the information—when the water overflows the thimble—we’re unable to retain the information or to draw connections with the information already stored in our long-term memory. We can’t translate the new information into schemas. Our ability to learn suffers, and our understanding remains shallow. Because our ability to maintain our attention also depends on our working memory—“we have to remember wha...

This is the core of the book.

Using the Net may, as Gary Small suggests, exercise the brain the way solving crossword puzzles does. But such intensive exercise, when it becomes our primary mode of thought, can impede deep learning and thinking. Try reading a book while doing a crossword puzzle; that’s the intellectual environment of the Internet.

Core

Navigating the Web requires a particularly intensive form of mental multitasking. In addition to flooding our working memory with information, the juggling imposes what brain scientists call “switching costs” on our cognition. Every time we shift our attention, our brain has to reorient itself, further taxing our mental resources. As Maggie Jackson explains in Distracted, her book on multitasking, “the brain takes time to change goals, remember the rules needed for the new task, and block out cognitive interference from the previous, still-vivid activity.”31 Many studies have shown that switching between just two tasks can add substantially to our cognitive load, impeding our thinking and increasing the likelihood that we’ll overlook or misinterpret important information.