The Nature vs. Nurture debate has a long history in our country bringing up questions of how much of whom we are is inherited from genetics and how much is acquired through our environment. Parents are always on the hot seat when it comes to how they raise their children. Can bad parenting lead a child to drop out of school or to have trouble with drugs or turn to a life of crime? While there is plenty of research for both sides of this debate, at least when it comes to your child's IQ, genetics seems to be the deciding factor.
In a study performed at Florida State University, criminology professor Kevin Beaver analyzed a group of adopted children from the National Longitudinal Study of Adolescent Health along with one comprised from a nationally representative sample of youths and discovered that IQ is not affected by how a child is raised. While reading to your child and having family dinners are great ways to connect with one another, they have no bearing on your child's intelligence as he grows older.
The study using an adoption-based research design looked at whether parenting behaviors had an effect on a child's verbal intelligence as measured by the Picture Vocabulary Test (PVT). Kids were given the IQ test in middle or high school, and then again when they were older, between 18 and 26.
Beaver told Science Daily, "Previous research that has detected parenting-related behaviors affect intelligence is perhaps incorrect because it hasn't taken into account genetic transmission."
When only studying children who are raised by their biological parents, it is not as easy to determine whether it is good parenting practices like reading to your child and helping them with their homework or a genetic transfer that made the child smarter. A parent who is more intelligent will mostly like engage in these positive parent behaviors making it difficult to separate out the two influences. By studying children living with adoptive parents, it is easier to make the distinction.
"In previous research, it looks as though parenting is having an effect on child intelligence, but in reality the parents who are more intelligent are doing these things and it is masking the genetic transformation of intelligence to their children," Beaver said.
He warned though that this research does not mean that parental neglect or abuse has no effect on a child. "The way you parent a child is not going to have a detectable effect on their IQ as long as that parenting is within normal bounds."
A full recording of the study's findings can be found in the journal Intelligence.