Exercise like walking, swimming, and even dancing have been shown to be good for your memory, but the optimal intensity of that exercise has been unclear... until now

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Neither approach is ideal. The best option is to temper your negative emotions by focusing on positive ones

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Horses picked out photographs of their current keepers, and even of former keepers whom they had not seen in months, at a rate much better than chance.

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What did you get your mother for Mother's Day? Was it beautifully thoughtful, or a rush job you fixed with a few clicks of the mouse and a credit card?

America is awash in secrets and conspiracies. Moviegoers are agog over the 2,000-year-old conspiracy theory in "The Da Vinci Code," which suggests that Jesus may not have died celibate. In a conspiracy exactly one order of magnitude smaller, Brad Meltzer's new novel, "The Book of Fate," tells about...

Jan Molinell lost $300,000 when Enron collapsed. A former Enron Corp. employee in Florida, Molinell closely followed the trials of Kenneth L. Lay and other Enron executives -- half-fearing that Lay's political ties to the White House would allow him to escape scot-free, and half-wondering whether an...

You don't have to be a sports fan to know that something extraordinary happened in the World Cup soccer final last week. Ten minutes from the climactic end -- with his country's hopes, the championship and his place in the history books at stake -- French captain Zinedine Zidane violently...

Office managers are under siege. They know that if they set the temperature to 74, they hear from the woman in human resources who says it is too cold. If they turn it up to 76, they hear from the man in marketing who wants to know why it is sweltering hot.

Both athletes were stars. Both faltered, then staged dramatic comebacks -- displaying the tenacity that separates heroes from also-rans. Both now face drug charges that could end their careers.

Is Pluto a planet? The world's astronomers met in Prague last week to vote on this question, and in a sort of cosmic game of "Survivor," they voted Pluto off the solar system.

For years, economists have taught their students a simple maxim: As employers hunt for workers, they want to get the best talent at the lowest price.

How the disaster starts does not matter: It could be a plane crashing into the World Trade Center, it could be the sea receding rapidly ahead of an advancing tsunami, it could be smoke billowing through a nightclub.

In 1935, researchers from Columbia University fanned out around the city of Allentown, Pa., and handed out leaflets ahead of local and state elections. What residents did not know was that they were part of an experiment in political persuasion -- an experiment whose results came to mind last week...

When George W. Bush takes the podium tomorrow night to deliver his sixth State of the Union address, what are the chances he will say this? "The war in Iraq has been one gigantic mistake. I am sorry I got us into this mess. I am going to bring the troops home right away."

Let's say someone stuck a microphone in your face and gave you 45 seconds to say something meaningful to a billion people. Let's say, moreover, that this is the only chance you will ever have to directly address the entire world.

The NCAA men's college basketball championship game was on the line. People in office pools around the country were holding their breath. Louisville was down by four points with a few minutes left on the clock. A UCLA player stole a pass and raced down the court where, after being bumped by a...

If Democrats Hillary Clinton and Barack Obama ever took a break from fundraising to bone up on psychology, they might realize the need to talk up . . . John Edwards.

President Bush said last week that his thinking on the U.S. situation in Iraq was informed by an analogy: the October 2000 bombing of the USS Cole in Yemen. The lack of a sufficient American response to that and other al-Qaeda attacks, Bush said, led to the Sept. 11, 2001, attacks.

Like most people in Virginia, Donald Black was horrified by Seung Hui Cho's shooting rampage last week that left 33 people dead, including the shooter.

Like lunar and solar eclipses, there are some Washington phenomena that are so common they ought to have distinct names. Here is one: A public figure comes to be hated by large numbers of people. But the person cannot be prosecuted or punished, perhaps because his behavior did not involve a crime so...

The ambitious immigration overhaul package that Congress is studying has drawn criticism from conservatives who say it offers amnesty to lawbreakers, and from immigration advocates who say it will not do enough to bring millions of people out of the shadows.

In the year 65, the Roman emperor Nero discovered that a group of nobles had hatched a conspiracy to kill him. The tyrant captured the suspects one by one and threatened them with torture; most confessed and implicated others. One of the conspirators, Epicharis, was publicly tortured -- her bones...

This year's National Basketball Association playoffs recently provided not one but two examples of a very interesting facet of human decision making. Even if you are not a sports fan, these moments tell you something about human nature.

A few days ago, Hamas fighters stormed Fatah strongholds in Gaza that were allied with Palestinian Authority President Mahmoud Abbas and effectively took control of one of the two pillars of the evolving Palestinian state. Fatah groups struck back in the West Bank, the other Palestinian pillar, and...

There are two ways to think about the staggering amounts of money given by special interest groups to politicians -- the type of contributions that were detailed for the last quarter in reports filed yesterday by presidential candidates and members of Congress.

Why would David Vitter, a U.S. senator with four young children, have gotten involved with a seedy escort service? Why would Michael Vick, a gifted NFL quarterback, get mixed up with the sordid world of dog fighting? Why would Bill Clinton, a Rhodes scholar, six-time governor and president of the...

Long before word recently broke that white referees in the National Basketball Association were calling fouls at a higher rate on black athletes than on white athletes, and long before studies found racial disparities in how black and white applicants get called for job interviews, researchers no...

As big Labor Day sales roll around, computer stores will tell you about laptops that now come with biometric fingerprint readers. Car companies will talk about "variable air suspension" features that allow you to change the ride of a car, depending on terrain. And video game manufacturers will ha...

John Duffy lost 67 of his colleagues at the firm of Keefe, Bruyette & Woods six years ago during the Sept. 11, 2001, terrorist attacks. Among the dead was Duffy's son Christopher. The investment banking firm, located in the South Tower of the World Trade Center, was among the companies hit hardes...

Four years ago, during a speech in Manila, President Bush drew an analogy between the history of the Philippines and the history he was rewriting in Iraq.

If you were Barack Obama, you would be scratching your head, too.

With just over five minutes to play in yesterday's game against the New York Jets, the Washington Redskins found themselves on their own 23-yard line facing a fourth and one. The team, which was ahead by just three points, elected to do what teams normally do in such situations: They played it safe...

What do the war in Iraq, your Christmas shopping and this week's Thanksgiving dinner have in common?

Scrooge crept towards it, trembling as he went; and following the finger, read upon the stone of the neglected grave his own name, Ebenezer Scrooge . . . "Spirit!" he cried, tight clutching at its robe, "hear me! I am not the man I was. I will not be the man I must have been . . . "

According to conventional wisdom, front-runners win presidential nominations. Democrats and Republicans who start the race for a presidential nomination with the largest amount of money and the best poll numbers are supposed to be the ones most likely to walk away with victory months later.

John McCain once called televangelists Pat Robertson and Jerry Falwell "agents of intolerance," but now the Republican senator from Arizona is currying favor with social conservatives. Sen. Hillary Rodham Clinton (D-N.Y.) now opposes the Iraq war, although she used to support it. Sen. Barack Obama...

People hate Mondays. And they love Fridays. The Carpenters crooned about being blue in "Rainy Days and Mondays." The restaurant chain T.G.I. Friday's might restrict its clientele to workaholics if it were to rename itself T.G.I. Monday's.

The housing market is in free fall: Quick -- let's protect homeowners against foreclosure.

Subprime mortgages have been linked to a meltdown in housing and questionable Wall Street practices, and they may have been the original domino that set off America's current economic crisis.

Seventeen years ago, a couple of criminologists at the University of Maryland published an interesting paper about the 1976 District ban on handguns -- a ban that was recently overturned by the Supreme Court on the grounds it was inimical to the constitutional right of Americans to bear arms to p...

Among psychologists who study sports, there is a code word for parents who lose their temper standing on the sidelines of their children's soccer, baseball and football games: THOSE parents -- Tempestuous, Harried, Overwrought, Self-absorbed and Emotional.

It happens all the time: Two guys in a garage come up with a cool new technology -- and dream of making it big. A thousand people take time off work to campaign for a visionary politician because they feel they are doing something to change the world. A million kids hit baseballs -- and wonder what...

Days before the Sept. 11, 2001, attacks, Osama bin Laden left his compound in Kandahar in Afghanistan and headed into the mountains. His driver, Salim Ahmed Hamdan, traveled with him. As U.S. and Northern Alliance forces stood poised to capture Kandahar a few months later, bin Laden told Hamdan t...

Have you seen the photo of Republican vice presidential nominee Sarah Palin brandishing a rifle while wearing a U.S. flag bikini? Have you read the e-mail saying Democratic presidential nominee Barack Obama was sworn into the U.S. Senate with his hand placed on the Koran? Both are fabricated -- and...

A few years ago, psychologists Mahzarin Banaji and Thierry Devos showed the names of a number of celebrities to a group of volunteers and asked them to classify the well-known personalities as American or non-American. The list included television personality Connie Chung and tennis star Michael ...

After nearly two years of political jockeying for the presidency, hundreds of millions of dollars of advertising and wall-to-wall campaign coverage in the media, nearly half of all Americans eligible to cast ballots in the presidential election may not bother to vote. Turnout for primaries, as well...

The Center for Responsive Politics recently estimated that it cost $5.8 billion to finance the 2008 general elections. To most people that is a staggeringly large sum and evidence of the profoundly corrupting role that money plays in politics, but to some very smart political watchers, the better...

Every time the White House changes hands between the Democrats and the Republicans, the outgoing party quickly sees the virtues of staffing government departments with competent managers. The incoming party invariably seeks to reward loyal campaign operatives with political appointments.

When nearly 200 people in India were killed in terrorist attacks late last month, the carnage received saturation media coverage around the globe. When nearly 600 people in Zimbabwe died in a cholera outbreak a week ago, the international response was far more muted.

Here's a trick question, so think carefully before you answer: If someone mentions the word "beast" to you, which word would you match it with?