A neuroscientist argues we’ve misunderstood the brain by focusing on individual neurons and unveils a new theory of how the brain really works.

In 2007, doctors in Marseille discovered that their patient had a gaping, fluid-filled hole in his brain. His neurons had disintegrated, severing the fragile connections that form the brain's communication system. And yet, the man’s only complaint was weakness in one leg. He could still read, remember, and reason. How was that possible?

The Latent Brain is the surprising answer. For decades, neuroscientists have insisted that our thoughts, feelings, and actions depend on the rapid electrical signals fired by each of the brain’s neurons. But they can’t explain why many neurons carry no useful information, or why, when neurons die, our behavior doesn’t necessarily change. Mark Humphries offers a radically new idea. Our mental lives, he argues, arise not from the activity of individual neurons but from collective signals formed by vast networks of neurons acting in concert. These signals guide our behavior; enable different brains to perform the same tasks; and even explain how we learn—why it's sometimes easy and sometimes devilishly hard. Humphries’s theory promises a revolution in neuroscience: a set of laws that map the activity of billions of neurons to the immense catalog of human behavior and experiences.

Bold, lucid, and ambitious, The Latent Brain is a big-idea science book by every measure.

Mark Humphries is Chair in Computational Neuroscience at the University of Nottingham and author of The Spike: An Epic Journey Through the Brain in 2.1 Seconds.