Rhaina Cohen

When we have a question about something embarrassing or deeply personal, many of us don't turn to a parent or a friend, but to our computers: We ask Google our questions.

As millions of us look for answers to questions, or things to buy, or places to meet friends, our searches produce a map of our collective hopes, fears, and desires.

We just can't let go of some decisions. We replay them in our head and imagine alternate endings.

These sorts of looping mental videos are called counterfactuals. Northwestern University Professor Neal Roese says there's real value to wondering "if only."

"Counterfactual thoughts are generally useful for us in terms of providing a set of options that we might act upon in the future," he says. "This can lead to improvement. It can lead to learning from experience."

After a disaster happens, we want to know, could something have been done to avoid it? Did anyone see this coming?

Many times, the answer is yes. There was a person — or many people — who spotted a looming crisis and tried to warn those in power. So why didn't the warnings lead to action?

"Fake news" is a phrase that may seem specific to our particular moment and time in American history.

But Columbia University Professor Andie Tucher says fake news is deeply rooted in American journalism.

In 1690, British officials forced the first newspaper in North America to shut down after it fabricated information. Nineteenth-century newspapers often didn't agree on basic facts. In covering a lurid murder in 1836, two major papers in New York City offered wildly differing perspectives on the case.

Many Americans find it adequate to represent their love and devotion to one person in a single ring on their left hand.

Author Briallen Hopper would need to enlist far more metal to represent her commitments. She would have to wear stacks of rings on each finger or a clanging forearm's worth of bracelets to signify each close friend, sibling, godchild, student, author, fictional character, and sentimentally-imbued object that receives her time and support.

Bababababa, dadadadada, ahgagaga. Got that?

Babies are speaking to us all the time, but most of us have no clue what they're saying. To us non-babies, it all sounds like charming, mysterious, gobbledegook. To researchers, though, babbling is knowable, predictable, and best of all, teachable. This week, we'll find out how to decipher the vocabulary, and the behavior, of the newest members of the human family.

In a way, all of us are time travelers. If we just pause and close our eyes we can wander back to our first kiss...our first breakup...that grandparent we should have visited...the summer that went on forever. This week, we explore two emotions that pull us into the past: regret and nostalgia. How can we make these feelings work for us, and what can we learn from them?

When Paul Kugelman was a kid, he had no shortage of friends. But as he grew older and entered middle age, his social world narrowed.

"It was a very lonely time. I did go to work and I did have interactions at work, and I cherished those," he says. "But you know, at the end of the day it was just me."

Kugelman's story isn't unusual: researchers say it can be difficult for men to hold on to friendships as they age. And the problem may begin in adolescence.

Women in the Middle Ages were excluded from many realms: the law,

All countries have national myths. The story of the first Thanksgiving, for example, evokes the warm glow of intercultural contact: European settlers, struggling to survive in the New World, and Native American tribes eager to help. But as many of us learned in history class, this story leaves a lot out.

We take it for granted that nostalgia is an ordinary, harmless emotion. You won't get a referral for a psychologist because you've posted a childhood photo with the caption #ThrowbackThursday, or because you have a weak spot for Lucky Charms or Fruit Roll-Ups. But that's a relatively new way of thinking.

The scientist who coined the term "nostalgia" in 1688 thought of this emotion as a neurological illness caused by demons. Other scientists latched onto this conception of nostalgia as a disease. It took marketers, centuries later, to realize that nostalgia has benefits.

Olutosin Oduwole was in his dorm room at Southern Illinois University when police knocked on his door one day in 2007. They were there to arrest him.

"In my mind I'm thinking, 'Okay, maybe a warrant for a ticket.' I really didn't know what was going on," he says.

What was going on was that the police suspected that Olutosin, a college student and aspiring rapper, was on the brink of committing a Virginia Tech-style mass shooting on his campus. He was soon charged with attempting to make a terrorist threat, and was eventually convicted and sent to prison.