Well it depends on which part you are interested in.

The Neuroscience book by Mark Bear gives a nice introductory overview of the biology behind a lot of neural processes: https://www.amazon.com/Neuroscience-Exploring-Mark-F-Bear/dp...

If you're interested in computational neural models, I would highly recommend Wolfgram Gerstner's recent book (available for free online): http://neuronaldynamics.epfl.ch

The book by Dayan and Abbot on theoretical neuroscience is quite nice too: https://mitpress.mit.edu/books/theoretical-neuroscience

After this, you'll probably want to read new review papers, since it's a field that's moving quite fast now. (Especially with new measurement techniques in the past few years)

Is there a way to tell if this book has DRM?

http://www.amazon.com/Neuroscience-Exploring-the-Brain-ebook...