(MONEY Magazine) – The next time you have a big financial decision to make, have someone tell you a joke first. Cornell University psychology professor Alice M. Isen has found that positive affect--that is, being in a good mood--helps you make better decisions and solve problems more creatively. So cheer up and save.

Q Feeling up, feeling so-so, feeling a little grumpy--why does it matter? A There's strong evidence that positive affect can help you find innovative answers to problems. We've seen it over and over. We do what we call the candle test: Give people a candle, a book of matches and a box of tacks and ask them to affix the candle to the wall so that it will burn without dripping on the floor or the wall. The rate of the solution in the control condition [neutral mood] is 10% to 13%. In the positive-affect condition--we showed them 1950s-era TV bloopers--it varies from 55% to 75%.

Q If I'm buying a house or making a budget, should I do it when I'm happy? A Sure. It will help you see different opportunities and alternative ways you might use your money. In our experiments we give people a compliment or show them pictures of puppies and then perform tests like the one we did with doctors who were thinking through diagnoses. The doctors in the control group were more likely to ignore information that didn't fit with their initial hypothesis rather than accept that they weren't right at first.

Q What's the scientific tie between good feelings and good decisions? A We call it the dopamine hypothesis. In positive affect, we believe the parts of the brain that have dopamine receptors are activated, and those are the regions responsible for thinking and working memory.

Q Just how far can a picture of puppies get me? A There's momentum at work here. You feel good, you come up with a more creative solution or the right answer, and that makes you happy too. Has this talk made you happy? Did you figure out the candle test yet?

Q I'm working on it. Don't tell me![*]

[*] THE ANSWER Empty the tacks from the box, tack the box to the wall, and stand the candle upright in the box.

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