A thorough examination of the topic: "What is the Internet doing to our brains?" Carr pulls together a broad range of experiences, reports and research studies to evaluate, though not necessarily draw conclusions, of how our use of computers, and particularly our use of the internet, is literally reshaping our brains. There is a lot of good material in this book, including some ideas on how to enhance your brain.
Interesting tidbit: when reading off of a paper, our eyes are drawn line by line, row to row in a zig-zag fashion (left to right, top to bottom). When reading off an electronic display (e.g. computer, phone, tablet, etc.) our eyes are drawn across the first line of the page, down the left side until the half way point, across the half way point and then down the left side to the bottom of the page (in an "F" shaped pattern). This means, as proved in numerous studies, that students learn and retain more from an actual book than from electronic books. Which is almost ironic to consider how hard schools are pushing ebooks on their students that will inherently result in slower, more difficult learning.
(Note: these patterns are for the Latin based world, that is English, French, German, etc. Arabic and other language bases have their own distinct patterns that the eyes follow.)