Children who showed high levels of hyperactivity and inattentiveness as kindergartners were much more likely to buy lotto tickets, bet on sports, and play video poker in the sixth grade than were less impulsive students. This suggests that impulsivity is a “developmentally continuous” trait that can lead to a lifetime of risky behavior. And since youthful wagering often precedes compulsive gambling—which leads to poor health, criminality, and substance abuse—it could “easily unravel into a public health issue.”

—“Predicting Gambling Behavior in Sixth Grade From Kindergarten Impulsivity,” Archives of Pediatrics & Adolescent Medicine

iPods are as ubiquitous on today’s college campuses as pens and notebooks, and they may make better learning tools. Students who listened to a lecture podcast and took notes scored far better on exams than students who attended the class in person. A majority in the podcast groupalso listened to the lecture more than once while studying, gaining an edge on peers who may or may not have been napping in the lecture hall.

—“iTunes University and the Classroom: Can Podcasts Replace Professors?,” Computers & Education

Nerds never win—in fact, they make significantly less money as adults than their cooler classmates. Men who’d been popular as high-school seniors were making more money, 35 years later, than their less popular peers, even after controlling for family background and intelligence. Just one additional high-school friendship resulted in roughly half the income gain from an extra year of education, and “turning a social reject into a star” would “yield him a 10 percent wage advantage.”

—“Popularity,” Institute for Social & Economic Research

How do our minds differentiate between a novel’s heroes and its villains? Evolutionary psychology suggests one answer. When asked to consider characters in 19th-century British novels, readers consistently identified as protagonists those who were more conscientious and likely to form alliances—behavior that fulfills “an adaptive social function.” Those they labeled antagonists were status-seeking, power-hungry, and selfish—all traits that work against the “egalitarian social dynamic” that our ancestors valued. Novels may allow us to live vicariously in idealized societies, or they may encourage us to acquire socially beneficial traits.

—“Hierarchy in the Library: Egalitarian Dynamics in Victorian Novels,” Evolutionary Psychology

The bonuses bankers have handed themselves in recent years aren’t just excessive—they may have hastened Wall Street’s collapse. Although cash incentives tend to make people work harder, expending too much effort can actually hinder tasks that require creativity, problem solving, and concentration. Anticipating large bonuses can lead to excessive self-consciousness and a focus so narrow that it warps perspective by blocking important outside information—like, say, common sense.

—“Large Stakes and Big Mistakes,” Review of Economic Studies

Last November’s rampage in Mumbai wasn’t an ordinary terrorist attack—the group behind it is part of a new “strategic terrorist culture” that presents as big a threat as al-Qaeda. Since counterterrorism forces worldwide have focused on preventing suicide bombings and other explosive attacks, Lashkar-e-Taiba (the group thought to be responsible) supplemented its use of bombs with gunfire, completely overwhelming the Indian police. And because they planned the attack impeccably, the terrorists roiled politics in India and Pakistan to their advantage, dominated international media coverage, and sparked pervasive fear among the Indian elite. “This indicates a level of strategic thought—a strategic culture—that makes this terrorist foe particularly dangerous.”

—“The Lessons of Mumbai,” Rand Corporation