If you must treat yourself to retail therapy, get this

That old saying "money can’t buy happiness" doesn’t really hold true. It's good news if you're in need of a mood boost and have a little extra cash on hand — and emphasizing the little part. According to research at San Francisco State University, if you want to improve your state of mind, you don’t need to max out your credit card to get a much-needed happy surge.

To establish a connection between consumer purchases and happiness levels, psychology researchers asked more than 370 consumers about their most recent purchases and how those purchases made them feel. After examining the results, they discovered that experiential products such as books, sporting goods, DVDs, videogames and musical instruments made people as happy as buying life experiences such as trips or theatre tickets. And previous studies have suggested that people who spend their money on life experiences enjoy greater happiness than people who spend their money on material goods. What is it about life experiences and experiential products that make them such good investments in psychological well-being?

The San Francisco researchers concluded that these kinds of purchases affirm certain basic psychological needs. Life experiences make people feel closer to others and offer a valid form of identity expression, while experiential products make people feel good because they draw on skills and knowledge.

Taken together, the findings offer a kind of psychological key on what to buy during certain periods of personal discontent. "If you're not feeling very competent, the best way to alleviate that deprivation would be through the use of experiential products,” Ryan Howell, an associate professor of psychology at SF State and co-author of the study, said in a statement.

“On the other hand, if you're feeling lonely, you should buy life experiences and do things with others."