Physically abused kids learn to fail at social rules for success

Physical abuse at home doesn’t just leave kids black and blue. It also bruises their ability to learn how to act at school and elsewhere, contributing to abused children’s well-documented behavior problems.

Derailment of a basic form of social learning has, for the first time, been linked to these children’s misbehavior years down the line, psychologist Jamie Hanson of the University of Pittsburgh and colleagues report February 3 in the Journal of Child Psychology and Psychiatry. Experiments indicate that physically abused kids lag behind their nonabused peers when it comes to learning to make choices that consistently lead to a reward, even after many trials.

“Physically abused kids fail to adjust flexibly to new behavioral rules in contexts outside their families,” says coauthor Seth Pollak, a psychologist at the University of Wisconsin–Madison. Youth who have endured hitting, choking and other bodily assaults by their parents view the world as a place where hugs and other gratifying responses to good behavior occur inconsistently, if at all. So these youngsters stick to what they learned early in life from volatile parents — rewards are rare and unpredictable, but punishment is always imminent. Kids armed with this expectation of futility end up fighting peers on the playground and antagonizing teachers, Pollak says.

If the new finding holds up, it could lead to new educational interventions for physically abused youth, such as training in how to distinguish safe from dangerous settings and in how to control impulses, Pollak says. Current treatments focus on helping abused children feel safe and less anxious.

More than 117,000 U.S. children were victims of documented physical abuse in 2015, the latest year for which data are available.

“Inflexible reward learning is one of many possible pathways from child maltreatment to later behavior problems,” says Stanford University psychologist Kathryn Humphreys, who did not participate in the new study. Other possible influences on physically abused kids’ disruptive acts include a heightened sensitivity to social stress and a conviction that others always have bad intentions, Humphreys suggests.

Hanson’s team studied 41 physically abused and 40 nonabused kids, ages 12 to 17. Participants came from various racial backgrounds and lived with their parents in poor or lower middle-class neighborhoods. All the youth displayed comparable intelligence and school achievement.

In one experiment, kids saw a picture of a bell or a bottle and were told to choose one to earn points to trade in for toys. Kids who accumulated enough points could select any of several desirable toys displayed in the lab, including a chemistry set and a glow-in-the-dark model of the solar system. Fewer points enabled kids to choose plainer toys, such as a Frisbee or colored pencils.

Over 100 trials, one picture chosen at random by the researchers at the start of the experiment resulted in points 80 percent of the time. The other picture yielded points 20 percent of the time. In a second round of 100 trials using pictures of a bolt and a button, one randomly chosen image resulted in points 70 percent of the time versus 30 percent for the other image.

Both groups chose higher-point images more often as trials progressed, indicating that all kids gradually learned images’ values. But physically abused kids lagged behind: They chose the more-rewarding image on an average of 131 out of 200 trials, compared with 154 out of 200 trials for nonabused youth. The abused kids were held back by what they had learned at home, Pollak suspects.