Why should we bother reading a book? All children say this occasionally. Many of the 12 million adults in Britain with reading difficulties repeat it to themselves daily. But for the first time in the 500 years since Johannes Gutenberg democratised reading, many among our educated classes are also asking why, in a world of accelerating technology, increasing time poverty and diminishing attention spans, should they invest precious time sinking into a good book?

The beginnings of an answer lie in the same technology that has posed the question. Psychologists from Washington University used brain scans to see what happens inside our heads when we read stories. They found that "readers mentally simulate each new situation encountered in a narrative". The brain weaves these situations together with experiences from its own life to create a new mental synthesis. Reading a book leaves us with new neural pathways.

The discovery that our brains are physically changed by the experience of reading is something many of us will understand instinctively, as we think back to the way an extraordinary book had a transformative effect on the way we viewed the world. This transformation only takes place when we lose ourselves in a book, abandoning the emotional and mental chatter of the real world. That's why studies have found this kind of deep reading makes us more empathetic, or as Nicholas Carr puts it in his essay, The Dreams of Readers, "more alert to the inner lives of others".

This is significant because recent scientific research has also found a dramatic fall in empathy among teenagers in advanced western cultures. We can't yet be sure why this is happening, but the best hypothesis is that it is the result of their immersion in the internet and the quickfire virtual world it offers. So technology reveals that our brains are being changed by technology, and then offers a potential solution – the book.

Rationally, we know that reading is the foundation stone of all education, and therefore an essential underpinning of the knowledge economy. So reading is – or should be – an aspect of public policy. But perhaps even more significant is its emotional role as the starting point for individual voyages of personal development and pleasure. Books can open up emotional, imaginative and historical landscapes that equal and extend the corridors of the web. They can help create and reinforce our sense of self.

If reading were to decline significantly, it would change the very nature of our species. If we, in the future, are no longer wired for solitary reflection and creative thought, we will be diminished. But as a reader and a publisher, I am optimistic. Technology throws up as many solutions as it does challenges: for every door it closes, another opens. So the ability, offered by devices like e-readers, smartphones and tablets, to carry an entire library in your hand is an amazing opportunity. As publishers, we need to use every new piece of technology to embed long-form reading within our culture. We should concentrate on the message, not agonise over the medium. We should be agnostic on the platform, but evangelical about the content.

We must also get better at harnessing the ability of the internet to inform readers, and potential readers, about all the extraordinary new books that are published every year, and to renew their acquaintance with the best of Britain's rich literary tradition. The research shows that if we stop reading, we will be different people: less intricate, less empathetic, less interesting. There can hardly be a better reason for fighting to protect the future of the book.

• Nicholas Carr's The Dreams of Readers features in Stop What You're Doing and Read This!, a book of essays about the transformative power of reading. A version of Michael Rosen's essay for that book will appear in G2 on Monday 2 January