Three books explore the outside forces that influence our inner world

Find yourself feeling emotionally satisfied after a long gab session? In Friendfluence: The Surprising Ways Friends Make Us Who We Are (Doubleday, 2013), former Psychology Today editor Carlin Flora unravels what science says about how our buddies affect our behavior and well-being. Research shows, for instance, that having a close friendship (but not a spouse) can help reduce the risk of dying from coronary disease. Flora's investigation of friendship, its benefits and pitfalls, may help readers improve their own relationships.

Brushing your teeth may have become so routine that you do it without thinking. Although habits help to “free up our processing power for other thoughts,” writes psychologist Jeremy Dean, there is a flipside to this automatic pilot mode: some behaviors, like smoking, can be detrimental. In Making Habits, Breaking Habits (Da Capo Lifelong Books, 2013), Dean discusses our difficulties forming and breaking habits and reveals that changing our surroundings or rethinking an action can help add a good one or modify a bad one.

From mean-spirited taunts to subtle jibes, insults can pit people against one another. In A Slap in the Face: Why Insults Hurt—And Why They Shouldn't (Oxford University Press, 2013), philosophy professor William B. Irvine discusses why we hurl invective and how we can protect ourselves from the sting. Insults carry weight because we care how others view us, and Irvine suggests the best way to deal with them is to keep our cool and not fire back.