“The findings have been very consistent over the past 20 years,” said study author Joan Durrant, a psychologist at the University of Manitoba. “Physical punishment predicts only negative long-term outcomes.”
Besides increased aggression, spanking increases the likelihood of depression, anxiety, and even cheating and criminal behaviors when the child becomes an adult. It also weakens the parent-child bond so “parents have less influence in setting an example of morally correct behavior,” said Murray Straus, a University of New Hampshire sociologist who has been studying spanking for more than 20 years.
Researchers have improved their methods of studying spanking by assessing children through the years, rather than asking adults to remember how often they were spanked -- which can yield unreliable recollections.
“If a child ranks in the top fifth among peers for misbehaviors, does he move up or down in this ranking as he gets older and does this correlate with how often he was spanked?” said Straus. One of his landmark studies found that children who were spanked an average of twice a week to reduce physical aggression were more likely to have greater aggression two years later compared with those who weren’t spanked. Their risk increased along with the frequency of spanking.
A study published this week by other researchers found that even in cultures where spanking is considerable acceptable, kids who are spanked have the same increased risk of becoming more aggressive.
“Spanking is a traumatic experience that can cause small losses in the brain’s gray matter,” explained Straus, “causing behavioral changes.” His research also found that spanking was linked to a lowering of IQ levels in children who were frequently spanked.
“Of course, some kids aren’t harmed at all by spanking, just like some heavy smokers suffer no harm from cigarettes,” Straus said. “But they’re the lucky ones as opposed to the unlucky ones who suffer harmful side effects.”
The American Academy of Pediatrics has long recommended against physical punishment, saying its of “limited effectiveness and has potentially deleterious side effects.”
