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In 2009, Dr. Straus of the University of New Hampshire made news when his study on spanking and IQ was published. In the study, Dr. Straus and his colleagues found that children who were spanked had lower Iqs than those who were not spanked. Since the release of this study, I have come across a number of articles and Internet videos that discuss this study and other similar studies on the effects of spanking on IQ.
However, I have yet to come across an article or a study that offers any interpretation on why a negative correlation exists between spanking and IQ. In this post and follow up video I will do just that.
Spanking is violence, and violence induces trauma. When people experience trauma, especially children, it negatively affects their intellectual abilities. There have been numerous studies that have provided supporting evidence on how trauma deteriorates a person's intellectual abilities. Studies like this one and this one.
Further more, studies have also shown that children who have been exposed to chronic violence become more wired for aggression. Given that aggression in the brain stems from the brain's fight or flight limbic system, it stands to reason that children who spend more time responding to conflicts with an aggressive attitude, spend more time thinking with their primitive brain (which is mostly autonomous) than their cerebral brain, (which is mostly wired for logic). So when these children are compared to other children who have not been role molded chronic aggression, they perform more poorly on cognitive tests designed to measure a child's competency in using logic.
Then there are other children who have been chronically role modeled violence, but instead of responding with aggression towards conflicts, they respond with anxiety and fright. While research studies on the relationship between IQ and anxiety have been mixed and inconclusive to date, the information on trauma and IQ has been consistent. So therefore children whose experiences with trauma have led them to develop anxiety, tend to make more impulsive decisions when under stress, which leads to lifestyle of habitual transitions between crisis. People in crisis often find themselves utilizing their primitive brain as opposed to their cerebral brain.
In this blog post, I discuss a bundle of nerves called the uncinate fasiculus (UF) that connect from the amygdala (the emotional center of the brain) and the prefrontal cortex (problem solving center of the brain). The interesting thing about the UF is that in a research study, people with a weaker UF were rated as having high anxiety, while those with a strong connection where rated as being better at managing their experiences with anxiety. Perhaps children who were not spanked, where role modeled effective cognitive strategies on how to address conflicts and stressful situations, as opposed to those whose parents resorted to violence.
The good news is that trauma can be treated and psychological wounds can be healed, through intensive therapy. I believe that while it is important to educate as many people as possible about the correlation between spanking and lower IQ, more efforts need to be made in explaining the correlation both in medical and laymen's terms. This is because even with parents who don't spank their children, a lot of psychological wounds can be inflicted through words and emotional disengagement.
Ugo is a Psychotherapist and Life Coach, he is also the author of the books Anger Management 101 and How to End Your Panic Attacks.
