I recommend the book "The power of habit", written by Charles Duhigg, a NYT bestseller. WIt contains many years of academic research on psychology, and explains not only habit, but willpower.

Also, watch this video.

http://www.youtube.com/watch?v=cIuahuKtim4

And here's the book:

http://www.amazon.com/The-Power-Habit-What-Business/dp/14000...