DURHAM, N.H. -- University of New Hampshire researchers have found that children who are never or rarely spanked have higher scores on tests of cognitive ability than those who are frequently spanked. The findings are based on a nationally representative sample of 960 children who were ages 1 to 4 at the start of the study.
Murray Straus, co-director of the UNH Family Research Laboratory and the author of numerous studies on the after-effects of corporal punishment, and UNH post-doctoral research fellow Mallie Paschall unveil their latest findings today, Aug. 1, at the World Congress of Sociology in Montreal.
Straus and Paschall believe that one of the reasons children of non-spanking parents have higher test scores than other children may be that parents who did not use corporal punishment have to do more explaining and reasoning to get across why the child should or shouldn't do something.
"Some parents think this is a waste of time," says Straus, "but research shows that such verbal parent-child interactions enhance the child's cognitive ability."
The study took into account many other factors that could affect a child's cognitive ability: the mother's age and education, whether the father is present in the household, the number of children in the family, the mother's supportiveness and cognitive stimulation, ethnic group, and the child's age, gender and birth weight.
Straus and Paschall found that, after taking account of these other factors, each increase of one point on the six point corporal punishment scale was associated with an average decrease in cognitive ability from the first to the second testing of .45 points.
"The cognitive ability of the children who were not spanked in either of the two sample weeks increased, and the cognitive ability of children who were frequently spanked decreased," says Straus. "The children who were spanked didn't get dumber," he adds. "What the study showed is that spanking is associated with falling behind the average rate of cognitive development, not an absolute decrease in cognitive ability."
Straus continues: "We also found indirect support for the part of the theory which argues that one of the reasons for the higher cognitive ability of children spanked the least is because, in the absence of corporal punishment, parents use more verbal methods of control, such as explaining to the child. We found that the less corporal punishment the mothers in this sample used, the more cognitive stimulation they provided to the child."
Straus and Paschall also point out the trend in the U.S. and many other countries away from the use of corporal punishment could be one of the reasons behind the corresponding increases in scores on IQ tests that have been recorded all over the world. "This could be coincidental, but it is also possible that the trend away from use of corporal punishment is part of the explanation for the increases in IQ scores. If so, ending or reducing corporal punishment takes on high priority."
In 1979 Sweden passed a no-spanking law. "It's an example of a non-punitive method of reducing corporal punishment," says Straus. "It provides money for public education and for helping parents. There are no punishments." Five countries have followed the Swedish example, and there are indications that other countries, such as Canada and Germany, also may ban corporal punishment.
American parents now use corporal punishment less frequently and for fewer years. However, studies by Straus and others find the majority continue to spank and slap children. "In view of the continuing prevalence of corporal punishment, if the findings of this study are confirmed by other studies, we should start media and educational programs to let parents know about the benefits of avoiding corporal punishment.
When parents spank, they can see that the child stops the wrong behavior," Straus explains. "But they have no way of looking into the future to see the harmful side effects. If parents knew the risk they were exposing their children to when they spank, I am convinced millions would stop."
A reduction in corporal punishment could have major benefits for children and society as a whole, Straus believes. "These benefits are not limited to enhanced mental ability," he says. "Recent research suggests that the benefits of less corporal punishment are likely to include less juvenile delinquency, less adult violence, less masochistic sex, a greater probability of completing higher education, higher income and lower rates of depression and alcohol abuse."
Straus and Paschall based their results on 960 children of mothers taking part in the National Longitudinal Study of Youth. These children were ages 1 to 4 in 1986. Their cognitive ability was measured in 1986 and 1990. The scores compare each child with other children within one month of the same age, setting the average score at 100. Corporal punishment was measured in 1986 and 1988 by whether the mother was observed hitting the child during the interview and by a question on how often she spanked in the past week. The corporal punishment scale was created by summing the scores for 1986 and 1988.