is an associate professor of Science and Technology in Society and a senior fellow of the Institute for Creativity, Arts, and Technology at Virginia Tech. He is the author of “Engineers for Change.”

How Digital Technologies Are Leaving Their Mark on Our Brains

By Susan Greenfield

Random House. 348 pp. $28

This is your brain on digital technology. A flick of the thumb sparks a pale glow. You wait for the dopamine rush of an incoming message. Like a pathological gambler, you check again. And again. You feed your narcissistic impulses with tweets. Lacking face-to-face cues, you knock a “friend” down a peg on Facebook. Keeping loneliness at bay, you “like” a few others. Hours of catapulted birds later, you finger the off button. Repeat the cycle. You hardly notice as the synapses of your true self fry away.

In “Mind Change,” neuroscientist, entrepreneur and British politician Susan Greenfield argues that our technologies are not only addictive — they are an existential threat. The brain, she writes, has an “evolutionary mandate to adapt to its environment,” and the digital world is changing at too rapid a pace for individuals or government regulations to keep up. Lives are destroyed. The extreme is the Korean couple whose compulsive video gaming led to the starvation of their newborn. But the warnings are no less ominous among billions of moderate users: a dramatic loss of empathy over the past decade and a precipitous decline in outdoor activity among children.

‘Mind Change: How Digital Technologies Are Leaving Their Mark on Our Brains’ by Susan Greenfield (Random House)

Since media theorist Marshall McLuhan’s pioneering work in the 1960s, a bevy of experts has explained what the electronic age is doing to us. Many, such as computer visionary Douglas Engelbart, assert that digital tools “augment” human intellect and foster interconnected democracy. Others, such as psychologist Sherry Turkle, whose 1984 masterpiece, “The Second Self,” studied the first generation of children raised on computers, have shifted from cautious optimism to disenchanted critique. Still others, such as technology writer Nicholas Carr, have been hostile, describing the life of the digital mind as a “shallows.”

Neuroscience, a field that seeks to be a scientific arbiter of social issues, seems tailor-made for evaluating our wired existence. Indeed, according to Greenfield, a healthy mind is like a healthy society. Just as individuals change with time, so do neurons, from the exploratory flexibility of youth to the restrained maturity of adulthood. A brain becomes a mind by coordinating “neuronal assemblies,” which work in harmony, gaining efficiency and stability as we emerge from adolescence. We reach the height of mindfulness when we acquire the logic of past, present and future in our decision-making. We experience the opposite, mindlessness, when we pursue sensation, impulsiveness and quick reward — the defining characteristics of children, addicts, the obese and “fast-paced sports, sex, dancing, or dreaming.”

Greenfield asserts that the digital revolution exploits our biological propensity for mindlessness. She cites laboratory studies finding that social networking and video gaming trigger dopamine in the same manner as junk food and Ecstasy. Moreover, she contends, because cyberspace lacks causal sequence, is devoid of immediate consequences and gives instant access to information without guidance, our attention spans shrink, deeper thinking declines and interpersonal bonds wither. Hardest hit are “Digital Natives,” whose “impressionable, plastic brains” are born into an environment that upends thousands of years of evolution.

“Mind Change” updates an old saw about technology and the decline of civilization. In the early 20th century, the eminent sociologist William Ogburn asked how society could evolve when humans had not changed biologically in 25,000 years. His answer was the then-novel concept of technological change. In his controversial government pamphlet “You and Machines” (1934), he contrasted “copper-skinned Indians” with atrophied, spoiled and divorce-prone Machine Age natives, who in less than a generation had lost connection with nature and tradition. Rapid technological advances were neither good nor evil, nor could they be stopped, requiring experts (like himself) to help government, industry and individuals adjust.

Greenfield’s application of the mismatch between human and machine to the brain introduces an important variation on this pervasive view of technology. Moreover, the field is exploring how to use digital technology itself (such as therapeutic video games) for combating the ill effects of digital technology. She offers a four-pronged strategy for confronting Mind Change: providing a larger stage for scientific experts in traditional media, undertaking surveys of societies across the world, ramping up funding for laboratory and epidemiological studies, and using software to counteract “deficiencies arising from excessive screen-based existence.”

Greenfield honed this neuro-policy in the public spotlight rather than in the laboratory. “Mind Change” grew out of a 2009 debate in Britain’s House of Lords, where she serves as a Life Member. Her standing as a celebrity scientist with a tendency for provocation has drawn the ire of critics. “Mind Change” came out in Britain last summer to heated reaction, including that of the Guardian’s science columnist, Martin Robbins, who wrote that it is hard not to take personally the book’s dismissiveness of the younger digital generation. Dorothy Bishop, a developmental neuropsychologist at Oxford, criticized Greenfield for implying that digital technology causes autism, and found it striking, as do I, that “Mind Change” cites anecdotal evidence such as Daily Mail articles, television psychologists, futurists and e-mails from friends almost as much as it does peer-reviewed research.

“Mind Change” is a missed opportunity. A “balanced and comprehensive overview” that puts neuroscience in conversation with psychology, media studies (such as “It’s Complicated,” Danah Boyd’s must-read look at teenagers’ digital lives) and technology policy could offer real insight into technology and the human condition. There are moments when Greenfield approaches such a synthesis, and she has rare talent for explaining science in accessible prose. But “Mind Change” is a polemic rather than a primer. It wields science as a rhetorical tool to energize supporters and rile those who would accuse her of what she calls “scaremongering.”

Greenfield begins “Mind Change” by comparing herself to an early climate scientist confronting a dismissive establishment. If she aspires to a similar paradigm shift, she and concurring experts will need more robust evidence and careful argument. Otherwise, they will change few minds.