(FORTUNE Magazine) – Mick Jagger still can't get no. And great philosophers like Schopenhauer were convinced it didn't exist. But real--and sustained--human contentment is indeed possible, according to Gregory Berns, author of Satisfaction: The Science of Finding True Fulfillment.

Berns, a psychiatrist and neuroscientist, has spent his academic career investigating happiness, or as he puts it, the circumstances under which the brain releases the "pleasure chemical" dopamine. Sex, drugs, or a good meal can increase dopamine levels. But startling noises and electric shocks can too. Berns concludes, then, in the book's central thesis, that pleasure is derived not from so-called "pleasant" experiences but from novel ones. "The sense of satisfaction after you've successfully handled unexpected tasks or sought out unfamiliar, physically and emotionally demanding activities is your brain's signal that you're doing what nature designed you to do," Berns notes.

Though Berns can be somewhat professorial, Satisfaction is no plodding textbook. The author embarks on an odyssey into the minds of thrill-seekers at crossword puzzle tournaments, at S&M clubs, and among ultramarathoners in the Sierra Nevada desert. Nothing escapes the author's investigative eye--not even his own sex life, which is "stuck in a rut." We'll spare you the details, but suffice it to say that Berns's gumshoe approach to scientific theory offers its own proof that a fresh take on the familiar can be most gratifying. -- John Simons