According to a new study, spanking negatively affects the behavior of toddlers in low-income families.
Published in the journal Child Development, the longitudinal study looked at how low-income parents discipline their young children.
It showed that spanking 1-year-olds leads to more aggressive behaviors and less sophisticated cognitive development in the next two years.
Verbal punishment, however, was not found to be associated with such effects, especially when it was accompanied by emotional support from mothers.
Besides, 1-year-olds' fussiness predicted spanking and verbal punishment at ages 1, 2, and 3.
The study explored whether mothers' behaviors lead to problematic behavior in children, whether children's challenging behaviors elicit harsher discipline, or both.
It looked at more than 2,500 exclusively low-income White, African American, and Mexican-American mothers and their young children, interviewing and observing them at home when the children were 1, 2, and 3 years old.
All participants' family incomes were at or below the federal poverty level.
Using their own interpretations of spanking, mothers reported how often anyone in the home had spanked their children in the past week.
The study also looked at how often mothers verbally punished-scolded, yelled, or made negative comments-their children.
It showed that African American children were spanked and verbally punished significantly more than the other children in the study.
The authors speculated that that might be due to cultural factors, such as belief in the importance of children's respect for elders and in the value of physical discipline to instil that respect.
Moreover, some African American mothers said that in preparing their children for a harsh, physically dangerous, and racially discriminating world, there was little room for error in their childrearing.
The study also shed light on information about the effects of such types of discipline.
"Our findings clearly indicate that spanking affects children's development," said Lisa J. Berlin, research scientist at the Center for Child and Family Policy at Duke University and the study's lead author.
Specifically, children who were spanked more often at 1 behaved more aggressively when they were 2, and had lower scores on tests measuring thinking skills when they were 3.
Similar findings were made even after taking into consideration such family characteristics as mothers' race and ethnicity, age, and education; family income and structure; and the children's gender.
The study also found that children who were more aggressive at age 2, and had lower cognitive development scores at ages 1 and 2, were not spanked more at ages 2 and 3.
"So the mothers' behaviors look more influential than the children's," said Berlin.
Unlike spanking, however, verbal punishment alone didn't affect either children's aggression or their cognitive development.
Interestingly, when verbal punishment was accompanied by emotional support from moms, the children did better on the tests of cognitive ability.