Brain Magnet is a book about the emergence of the knowledge economy in the United States by Alex Sayf Cummings, associate professor of History at Georgia State University and author of the book Democracy of Sound (Oxford, 2013).  It was published in March 2020 by Columbia University Press as part of its Studies in the History of U.S. Capitalism series, and is available in hardcover, paperback, and e-book formats.

For a taste of the book, see this 2015 article in the Journal of Urban History.