As someone who has enjoyed and learned a lot from Steven Pinker’s books about language and cognition, I was disappointed to see the Harvard psychologist write, in Friday’s New York Times, a cursory op-ed column about people’s very real concerns over the Internet’s influence on their minds and their intellectual lives. Pinker seems to dismiss out of hand the evidence indicating that our intensifying use of the Net and related digital media may be reducing the depth and rigor of our thoughts. He goes so far as to assert that such media “are the only things that will keep us smart.” And yet the evidence he offers to support his sweeping claim consists largely of opinions and anecdotes, along with one very good Woody Allen joke.

One thing that didn’t surprise me was Pinker’s attempt to downplay the importance of neuroplasticity. While he acknowledges that our brains adapt to shifts in the environment, including (one infers) our use of media and other tools, he implies that we need not concern ourselves with the effects of those adaptations. Because all sorts of things influence the brain, he oddly argues, we don’t have to care about how any one thing influences the brain. Pinker, it’s important to point out, has an axe to grind here. The growing body of research on the adult brain’s remarkable ability to adapt, even at the cellular level, to changing circumstances and new experiences poses a challenge to Pinker’s faith in evolutionary psychology and behavioral genetics. The more adaptable the brain is, the less we’re merely playing out ancient patterns of behavior imposed on us by our genetic heritage.

In Adapting Minds, his epic critique of the popular brand of evolutionary psychology espoused by Pinker and others, David J. Buller argues that evolution “has not designed a brain that consists of numerous prefabricated adaptations,” as Pinker has suggested, but rather one that is able “to adapt to local environmental demands throughout the lifetime of an individual, and sometimes within a period of days, by forming specialized structures to deal with those demands.” To understand the development of human thought, and the influence of outside influences on that thought, we need to take into account both the fundamental genetic wiring of the brain – what Pinker calls its “basic information-processing capacities” – and the way our genetic makeup allows for ongoing changes in that wiring.

On the topic of neuroplasticity, Pinker claims to speak for all brain scientists. When confronted with suggestions that “experience can change the brain,” he writes, “cognitive neuroscientists roll their eyes.” I’m wary when any scientist suggests that his view of a controversial matter is shared by all his colleagues. I also wonder if Pinker read the reports on the Net’s cognitive effects published in the Times last week, in which several leading brain researchers offer views that conflict with his own. A few examples:

“The technology is rewiring our brains,” said Nora Volkow, director of the National Institute of Drug Abuse and one of the world’s leading brain scientists … The nonstop interactivity is one of the most significant shifts ever in the human environment, said Adam Gazzaley, a neuroscientist at the University of California, San Francisco. “We are exposing our brains to an environment and asking them to do things we weren’t necessarily evolved to do,” he said. “We know already there are consequences” … [Stanford professor Clifford] Nass says the Stanford studies [of media multitasking] are important because they show multitasking’s lingering [cognitive] effects: “The scary part for guys like Kord is, they can’t shut off their multitasking tendencies when they’re not multitasking.”

In a brief essay published last week on the Times website, Russell A. Poldrack, the director of the Imaging Research Center and professor of psychology and neurobiology at the University of Texas at Austin, wrote: “Our research has shown that multitasking can have an insidious effect on learning, changing the brain systems that are involved so that even if one can learn while multitasking, the nature of that learning is altered to be less flexible. This effect is of particular concern given the increasing use of devices by children during studying.”

Other scholars of the mind also believe, or at least worry, that our use of digital media is having a deep, and not necessarily beneficial, influence on our ways of thinking. The distinguished neuroscientist Michael Merzenich, who has been studying the adaptability of primate brains since the late 1960s, believes that human brains are being significantly “remodeled” by our use of the Net and other modern media. Maryanne Wolf, a developmental psychologist at Tufts, fears that the shift from immersive page-based reading to distracted screen-based reading may impede the development of the specialized neural circuits that make deep, richly interpretive reading possible. We may turn into mere “decoders” of text.

Pinker may well disagree with all these views, but to pretend they don’t exist is misleading.

Pinker also pokes at straw men. Instead of grappling with the arguments of others, he reduces them to caricatures in order to dismiss them. He writes, for example, that “the existence of neural plasticity does not mean the brain is a blob of clay pounded into shape by experience.” Who exactly does Pinker believe is proposing such an idea – John Locke? I haven’t seen anyone suggest that the brain is a shapeless blob of clay. What they are saying is that the brain, while obviously as much a product of evolution as any other part of the body, is not genetically locked into rigid modes of thought and behavior. Changes in our habits of thought echo through our neural pathways, for better and for worse.

In other cases, Pinker uses overstatement to gloss over subtleties. He writes at one point, “If electronic media were hazardous to intelligence, the quality of science would be plummeting.” Human intelligence takes many forms. Electronic media may enhance some aspects of our intelligence (the ability to spot patterns in arrays of visual data, for example, or to discover pertinent facts quickly or to collaborate at a distance) while at the same time eroding others (the ability to reflect on our experiences, say, or to express ourselves in subtle language or to read complex narratives critically). To claim that “intelligence” can be gauged by a single measure is to obfuscate rather than illuminate.

Pinker notes that “the decades of television, transistor radios and rock videos were also decades in which I.Q. scores rose continuously.” Actually, as the political scientist James Flynn first documented, general IQ scores have been rising at a steady clip since the beginning of the 1900s, so we should be wary about linking this long-term trend to the recent popularity of any particular technology or medium. Moreover, as Flynn himself has been careful to point out, the improvements in IQ scores are largely attributable to increases in measures of visual acuity and abstract problem-solving, such as the mental rotation of geometric forms, the identification of similarities between disparate objects, and the arrangement of shapes into logical sequences. These skills are certainly very important, but measures of other components of intelligence, including verbal skill, vocabulary, basic arithmetic, memorization, critical reading, and general knowledge, have been stagnant or declining. In warning against drawing overly broad conclusions about our intelligence from the rise in IQ scores, Flynn wrote, in his book What Is Intelligence?, “How can people get more intelligent and have no larger vocabularies, no larger stores of general information, no greater ability to solve arithmetical problems?”

Drifting briefly from science to the humanities, Pinker implies that our cultural life is richer than ever, a consequence, apparently, of the bounties of digital media. As evidence, he points to the number of stories appearing on the website Arts & Letters Daily. Suffice it to say that other indicators of the depth and richness of cultural life point in different directions.

Pinker also makes several observations that, while accurate, undercut the main thrust of his argument. He writes, for example, that “the effects of experience are highly specific to the experiences themselves. If you train people to do one thing (recognize shapes, solve math puzzles, find hidden words), they get better at doing that thing, but almost nothing else.” Well, yes, and that’s why some of us are deeply concerned about society’s ever-increasing devotion to the Net and other screen-based media. (The average American now spends more than eight hours a day peering into screens, while devoting only about 20 minutes to reading books and other printed works.) It’s hard not to conclude, or at least suspect, that we are narrowing the scope of our intellectual experiences. We’re training ourselves, through repetition, to be facile skimmers, scanners, and message-processors – important skills, to be sure – but, perpetually distracted and interrupted, we’re not training ourselves in the quieter, more attentive modes of thought: contemplation, reflection, introspection, deep reading, and so forth.

And there’s this: “Genuine multitasking, too, has been exposed as a myth, not just by laboratory studies but by the familiar sight of an S.U.V. undulating between lanes as the driver cuts deals on his cellphone.” Precisely so. Which is one of the reasons that many experts on multitasking are concerned about its increasing prevalence. People may think, as they juggle emails, texts, tweets, updates, Google searches, glances at web pages, and various other media tasks, that they’re adeptly doing a lot of stuff all at once, but what they’re really doing is switching constantly between different tasks, and suffering the cognitive costs that accompany such switching. As Steven Yantis, a professor of psychological and brain sciences at Johns Hopkins, told the Times:

In addition to the switch cost, each time you switch away from a task and back again, you have to recall where you were in that task, what you were thinking about. If the tasks are complex, you may well forget some aspect of what you were thinking about before you switched away, which may require you to revisit some aspect of the task you had already solved (for example, you may have to re-read the last paragraph you’d been reading). Deep thinking about a complex topic can become nearly impossible.

The fact that people who fiddle with cell phones drive poorly shouldn’t make us less concerned about the cognitive effects of media distractions; it should make us more concerned.

And then there’s this: “It’s not as if habits of deep reflection, thorough research and rigorous reasoning ever came naturally to people.” Exactly. And that’s another cause for concern. Our most valuable mental habits – the habits of deep and focused thought – must be learned, and the way we learn them is by practicing them, regularly and attentively. And that’s what our continuously connected, constantly distracted lives are stealing from us: the encouragement and the opportunity to practice reflection, introspection, and other contemplative modes of thought. Even formal research is increasingly taking the form of “power browsing,” according to a 2008 University College London study, rather than attentive and thorough study. Patricia Greenfield, a professor of developmental psychology at UCLA, warned in a Science article last year that our growing use of screen-based media appears to be weakening our “higher-order cognitive processes,” including “abstract vocabulary, mindfulness, reflection, inductive problem solving, critical thinking, and imagination.”

We should all celebrate, along with Pinker, the many benefits that the Net and related media have brought us. I have certainly enjoyed those benefits myself over the last two decades. And we should heed his advice to look for “strategies of self-control” to ameliorate the distracting and addictive qualities of those media. But we should not share Pinker’s complacency when it comes to the Net’s ill effects, and we should certainly not ignore the mounting evidence of those effects.