Daniel Levitin was a successful musician and producer many years ago. During that time, he gained an interest in the science behind the music he was making. Why do certain songs get stuck in your head? Why are some people able to play their instruments better than others? Why do we hear music the way we do? So, Levitin earned a PhD and became a researcher about the brain and how it 'decodes' music. He's compiled much of what he has learned into this book.
Although the topic sounds like it might make for dry reading, Levitin writes in a clear, concise style that even us dumb musicians can understand and much of what he reveals in the book is truly fascinating. This book obviously won't make you a better musician or songwriter, but it will certainly make you a better informed one!