The power of a revocable bonus

With budgets for education tightening across the country, it pays to get the best performance out of teachers. Economists may have found a way to do just that. They conducted an experiment at a poor, minority school district near Chicago where they randomly assigned some teachers to receive end-of-year bonuses based on student improvement, while other teachers received upfront bonuses that could be revoked at the end of the year if student improvement was below average. In other words, the only difference was the timing of the bonus. There were “large and statistically significant gains” on math test scores when bonuses were paid upfront, but not when bonuses were paid at the end of the year. Thus, the prospect of having to give back money they had already received was more motivating for teachers than the prospect of getting money.


Fryer, R. et al., “Enhancing the Efficacy of Teacher Incentives through Loss Aversion: A Field Experiment,” National Bureau of Economic Research (July 2012).

How brains recover from orphanages

Research has shown that children in institutional care suffer developmental deficits that can be seen in the brain, but a new study suggests that all is not lost. Some infants and toddlers living in orphanages in Romania were randomly assigned to foster care, while another group remained in the orphanages; later, as older children, all of them underwent brain scans. Although some aspects of brain anatomy were deficient in these children relative to never-institutionalized children regardless of whether they had left the orphanages, other aspects of brain anatomy in children assigned to foster care appeared to “catch up.”

Sheridan, M. et al., “Variation in Neural Development as a Result of Exposure to Institutionalization Early in Childhood,” Proceedings of the National Academy of Sciences (forthcoming).

Forgive, don’t forget

When someone wrongs you, do you actually forgive them, or just try to forget and focus on other things? New research from the University of California San Diego suggests you might want to try forgiveness, because forgetting doesn’t really work. Students were hooked up to a blood pressure monitor and were then asked to recall an incident where an acquaintance had hurt or offended them. Some students were then told to think about forgiving the offender, while others were told to ruminate on the incident, and others were told to distract themselves by thinking about the previous weekend. Not only did thinking about forgiveness cause the smallest increase in blood pressure in the short term, but it was also significantly better than distraction over a longer period of time. In fact, distraction became as bad for blood pressure as rumination or even worse.


Larsen, B. et al., “The Immediate and Delayed Cardiovascular Benefits of Forgiving,” Psychosomatic Medicine (forthcoming).

The militant middle class

In some foreign policy circles, it has become conventional wisdom that grinding poverty feeds extremism, and that the poor tend to be the staunchest supporters of extremist political groups. However, a recent survey—“arguably the first valid, national measurement of attitudes toward militant groups in Pakistan,”according to its authors—challenges this assumption. The middle class was far more supportive of militant groups than the poor, especially the urban poor, largely because the urban poor bear the brunt of much of the violence caused by militant groups. The authors conclude that “it is unlikely that improving the material well-being of individuals will reduce support for violent political organizations.”


Blair, G. et al., “Poverty and Support for Militant Politics: Evidence from Pakistan,” American Journal of Political Science (forthcoming).

Mind vs. body

I think, therefore I can let my body go. That’s the metaphysical gist of a new study on the connection between mind-body dualism—i.e., thinking that the mind and body are two distinct entities—and being physically unhealthy. In a series of experiments, researchers found that putting people in a dualist frame of mind caused them to report less positive attitudes towards, and less engagement in, healthy eating and behavior. The effect also went the other way: Pictures of unhealthy food caused people to report a stronger belief in mind-body dualism.

Forstmann, M. et al., “‘The Mind Is Willing, but the Flesh Is Weak’: The Effects of Mind-Body Dualism on Health Behavior,” Psychological Science (forthcoming).

Kevin Lewis is an Ideas columnist. He can be reached at kevin.lewis.ideas@gmail.com.