Narrator: This is Science Today. So, you have a strong marriage, nice kids, a new house and received a raise at work. And yet, you're not feeling very happy — or at least not as happy as you think you should be. Well, you're not alone. In fact, psychologist Sonja Lyubomirsky of the University of California, Riverside, says it's part of a universal process called hedonic adaptation.
Lyubomirsky: Hedonic adaptation is basically the phenomenon that human beings are remarkably good at getting used to changes in their lives, especially positive changes. We are very happy initially, but that happiness tends to fade with time. Scientists believe that hedonic adaptation is evolutionarily adaptive because it's adaptive for us to be alert or vigilant about change. You know, because any kind of change in the environment could be a signal for opportunity for reward or a threat or a danger. So, when a relationship or a job or your car becomes familiar and sort of stays the same, then we tend to take it for granted. We stop paying attention to it.
Narrator: For Science Today, I'm Larissa Branin.