Experts found a new, low-cost method to treat mild depression – teaching people to practice positive activities.

Researchers at the University of California, Riverside and Duke University Medical Center termed the approach Positive Activity Interventions (PAI), in a paper published in the Journal of Alternative and Complementary Medicine.

PAIs are intentional activities, such as performing acts of kindness, practicing optimism and counting one’s blessings, and researchers believe this has the potential to benefit depressed individuals who don’t respond to pharmacotherapy or are not able or willing to obtain treatment, according to the report.

Led by Dr. Sonja Lyubomirsky, professor of psychology and director of the Positive Psychology Laboratory at University of California – Riverside; and Lihong Wang, MD, and P. Murali Doraiswamy, MBBS, FRCP, of Duke University, the research team reviewed previous studies done on PAIs, including randomized, controlled interventions with thousands of normal men and women, as well as functional MRI scans in people with depressive symptoms.

“Over the last several decades, social psychology studies of flourishing individuals who are happy, optimistic and grateful have produced a lot of new information about the benefits of positive activity interventions on mood and well-being,” Lyubomirsky said in the report.

Although the paper found that positive activity interventions are effective in teaching individuals ways to increase their positive thinking, positive effect and positive behaviors, only two studies specifically tested these activities in individuals with mild depression.

In one of these studies, lasting improvements were found for six months, and effective PAIs used in the study included writing letters of gratitude, counting one’s blessings, practicing optimism, performing acts of kindness, meditating on positive feelings toward others and using one’s signature strengths.

People often underestimate the long-term impact of practicing brief, positive activities, Lyubomirsky said. Additionally, during the research, reviewing brain imaging studies led the team to the theory that PAIs may act to boost the dampened reward/pleasure circuit mechanisms and reverse apathy – a key benefit that does not usually arise from treatment with medication alone, the study stated.

“The positive activities themselves aren’t really new,” said Kristin Layous, a graduate student and the paper’s lead author. “After all, humans have been counting their blessings, dreaming optimistically, writing thank-you notes, and doing acts of kindness for thousands of years. What’s new is the scientific rigor that researchers have applied to measuring benefits and understanding why they work.”