Shankar Vedantam

If I asked you to think of a murderer, what's the image that springs to mind?

If you're like most people, you'll probably think of an evil psychopath, or someone bent on revenge. Perhaps you'll see a criminal mastermind, who eliminates rivals on his way to riches. Or a strung-out drug addict, who kills because she needs money to get high.

All of these images have something in common: As a rule, we tend to associate murder with the behavior of individuals who behave in aberrational ways.

Have you ever wondered whether music conductors actually influence their orchestras?

They seem important. After all, they're standing in the middle of the stage and waving their hands. But the musicians all have scores before them that tell them what to play. If you took the conductor away, could the orchestra manage on its own?

Some time ago, a man wearing jeans, cowboy boots and a hoodie drove a dirty Ford Explorer into a carwash in Fort Worth, Texas. As soon as the car came back clean, he got it filthy again, and drove to the next carwash. He did this with every single full-service carwash in town.

The man wasn't suffering from a strange mental disorder; Patrick Kinkade was a criminologist conducting an experiment.

In January 2010, more than a year before Mitt Romney had formally announced he was running for president, political historian Allan Lichtman predicted President Obama would be re-elected in 2012.

Vampires and monsters will be out in force tonight, but some of the darkest creatures out there might be your little angels inside those Halloween costumes.

As part of NPR's coverage of this year's presidential election, All Things Considered asked three science reporters to weigh in on the race. The result is a three-part series on the science of leadership. In Part 1, Alix Spiegel looked at the personalities of American presidents. In Part 2, Jon Hamilton examined leadership in the animal kingdom.

At a recent academic conference, Michigan State University professor Natalie Phillips stole a glance around the room. A speaker was talking but the audience was fidgety. Some people were conferring among themselves, or reading notes. One person had dozed off.

When we think about morality, many of us think about religion or what our parents taught us when we were young. Those influences are powerful, but many scientists now think of the brain as a more basic source for our moral instincts.

Thinking of going to a nice restaurant? Before you decide, you probably go online and read reviews of the place from other customers (or you listen to these actors read them to you). Online reviews of restaurants, travel deals, apps and just about anything you want to buy have become a powerful driver of consumer behavior. Unsurprisingly, they have also created a powerful incentive to cheat.

If you're a student, you may have harbored the fantasy of learning lessons while you sleep. Who wouldn't want to stick on a pair of headphones, grab some shut-eye with a lesson about, say, Chinese history playing in his ears — and wake up with newly acquired knowledge of the Ming Dynasty?

Sadly, it doesn't work. The history lesson either keeps you from going to sleep, or it doesn't — in which case you don't learn it.

Independent voters have grown in recent years into a mega voting bloc. By some estimates they outnumber registered Republicans, and even registered Democrats.

Every election cycle, independents generate enormous amounts of interest as candidates, pollsters and the media probe their feelings. These voters are widely considered to hold the key to most elections.

It's Saturday night at the Metropolitan Room, a comedy club in New York City. Host Jimmy Failla is warming up the crowd.

"Where you guys from?" he asks one group in the audience. "Boston? Home of the Red Sox. Personally, we'd prefer you rooted for the Taliban!"

There are 50 or 60 people in the audience, sipping cocktails. Failla has a system. He asks people where they're from. Most are locals. He then hits them with something they can relate to.

Both athletes were U.S. swimmers, both were dripping wet after finishing an Olympics final, and both had just won medals.

The first said, "It's not my normal specialty. ... We went out there and raced tough – and just came up a little short."

The second had a beaming face. He said, "[I] swam my own race. And knew I had a lane, and had an opportunity, and I went for it. It worked out, you know, it's just awesome that I get to go on the podium tonight. Honestly, I'm really proud of myself!"

Marketers, managers and panhandlers all have something in common: They regularly want to make you do things they want. Marketers want you to buy stuff, managers want you to finish projects on time, and panhandlers want you to spare a buck, or three.

Over the years, psychologists have studied the techniques of manipulation and found several that seem to work. (Read on only if you agree to use these techniques for good and not for evil!)

Walk into any tech company or university math department, and you'll likely see a gender disparity: Fewer women than men seem to go into fields involving science, engineering, technology and mathematics.