The most psychologically correct holiday of the year is upon us.

Thanksgiving may be the holiday from hell for nutritionists, and it produces plenty of war stories for psychiatrists dealing with drunken family meltdowns. But it has recently become the favorite feast of psychologists studying the consequences of giving thanks.

Cultivating an “attitude of gratitude” has been linked to better health, sounder sleep, less anxiety and depression, higher long-term satisfaction with life, and kinder behavior toward others, including romantic partners. A new study shows that feeling grateful makes people less likely to turn aggressive when provoked, which helps explain why so many brothers-in-law survive Thanksgiving without serious injury.

But what if you’re not the grateful sort? I sought guidance from the psychologists who have made gratitude a hot research topic. Here’s their advice for getting into the spirit of the holiday — or at least getting through dinner on Thursday:

START WITH “GRATITUDE LITE”

That’s the term used by Robert A. Emmons, of the University of California, Davis, for the technique used in his pioneering experiments he conducted along with Michael E. McCullough of the University of Miami. They instructed people to keep a journal listing five things for which they felt grateful, like a friend’s generosity, something they’d learned, a sunset they’d enjoyed.

The gratitude journal was brief — just one sentence for each of the five things — and done only once a week, but after two months there were significant effects. Compared with a control group, the people keeping the gratitude journal were more optimistic and felt happier. They reported fewer physical problems and spent more time working out.

Further benefits were observed in a study of polio survivors and other people with neuromuscular problems. The ones who kept a gratitude journal reported feeling happier and more optimistic than those in a control group, and these reports were corroborated by observations from their spouses. These grateful people also fell asleep more quickly at night, slept longer and woke up feeling more refreshed.

“If you want to sleep more soundly, count blessings, not sheep,” Emmons advises in “Thanks!” his book on gratitude research.

DON’T CONFUSE GRATITUDE WITH INDEBTEDNESS

Sure, you may feel obliged to return a favor, but that’s not gratitude, at least not the way psychologists define it. Indebtedness is more of a negative feeling and doesn’t yield the same benefits as gratitude, which inclines you to be nice to anyone, not just a benefactor.

In an experiment at Northeastern University in Boston, Monica Bartlett and David DeSteno sabotaged each student participant’s computer and arranged for another student to fix it. Afterward, the students who had been helped were likelier to volunteer to help someone else — another complete stranger — with an unrelated task. Gratitude promoted good karma. And if it works with strangers …

TRY IT ON YOUR FAMILY

No matter how dysfunctional your family, gratitude can still work, says Sonja Lyubomirsky of the University of California, Riverside.

“Do one small and unobtrusive thoughtful or generous thing for each member of your family on Thanksgiving,” she advises. “Say thank you for every thoughtful or kind gesture. Express your admiration for someone’s skills or talents — wielding that kitchen knife so masterfully, for example. And truly listen, even when your grandfather is boring you again with the same World War II story.”

DON’T COUNTERATTACK

If you’re bracing for insults Thursday, consider a recent experiment at the University of Kentucky. After turning in a piece of writing, some of students received praise for it while others got a scathing evaluation: “This is one of the worst essays I’ve ever read!”

Then each student played a computer game against the person who’d done the evaluation. The winner of the game could administer a blast of white noise to the loser. Not surprisingly, the insulted essayists retaliated against their critics by subjecting them to especially loud blasts — much louder than the noise administered by the students who’d gotten positive evaluations.

But there was an exception to this trend among a subgroup of the students: the ones who had been instructed to write essays about things for which they were grateful. After that exercise in counting their blessings, they weren’t bothered by the nasty criticism — or at least they didn’t feel compelled to amp up the noise against their critics.

“Gratitude is more than just feeling good,” says Nathan DeWall, who led the study at Kentucky. “It helps people become less aggressive by enhancing their empathy. It’s an equal-opportunity emotion. Anyone can experience it and benefit from it, even the most crotchety uncle at the Thanksgiving dinner table.”

SHARE THE FEELING

Why does gratitude do so much good? “More than other emotion, gratitude is the emotion of friendship,” McCullough says. “It is part of a psychological system that causes people to raise their estimates of how much value they hold in the eyes of another person. Gratitude is what happens when someone does something that causes you to realize that you matter more to that person than you thought you did.”

TRY A GRATITUDE VISIT

This exercise, recommended by Martin Seligman of the University of Pennsylvania, begins with writing a 300-word letter to someone who changed your life for the better. Be specific about what the person did and how it affected you. Deliver it in person, preferably without telling the person in advance what the visit is about. When you get there, read the whole thing slowly to your benefactor. “You will be happier and less depressed one month from now,” Seligman guarantees in his book “Flourish.”

CONTEMPLATE A HIGHER POWER

Religious individuals don’t necessarily act with more gratitude in a specific situation, but thinking about religion can cause people to feel and act more gratefully, as demonstrated in experiments by Jo-Ann Tsang and colleagues at Baylor University in Waco, Texas. Other research shows that praying can increase gratitude.

GO FOR DEEP GRATITUDE

Once you’ve learned to count your blessings, Emmons says, you can think bigger.

“As a culture, we have lost a deep sense of gratefulness about the freedoms we enjoy, a lack of gratitude towards those who lost their lives in the fight for freedom, a lack of gratitude for all the material advantages we have,” he says. “The focus of Thanksgiving should be a reflection of how our lives have been made so much more comfortable by the sacrifices of those who have come before us.”

And if that seems too daunting, you can least tell yourself —

Hey, it could always be worse. When your relatives force you to look at photos on their phones, be thankful they no longer have access to a slide projector. When your aunt expounds on politics, rejoice inwardly that she does not hold elective office. Instead of focusing on the dry, tasteless turkey on your plate, be grateful the six-hour roasting process killed any toxic bacteria.

Is that too much of a stretch? When all else fails, remember the Monty Python mantra of the Black Plague victim: “I’m not dead.” It’s all a matter of perspective.

© 2011 The New York Times Company