Nature or nurture?

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This is a response to a discussion prompt from the course forum for 6411 Cognition and Learning.

I’ve always believed that intelligence is a combination of both nature and nurture. According to Kendler, Turkheimer, Ohlsson, Sundquist, and Sundquist (2015) studies with children who are adopted are strong examinations of the “environmental malleability of cognitive ability” (p. 4613). While the context is completely different and the population in the study didn’t include females, I couldn’t help but draw a personal connection. No, I don’t have adopted siblings, nor was I an adopted child. The one consideration I didn’t see mentioned in this study, as one of six siblings, and the parent of three children, is the inherent uniqueness of each child. No two siblings are even remotely the same to begin with. There are extreme differences between my siblings that can’t be attributed to parental school attendance or home environments, hence my belief in nature as a factor in intelligence.

What really caught my attention was your statement that “each one-point increase on the education scale resulted in 2.73 and 1.71 additional IQ points for the non-adopted and adopted children respectively” (Regalado, 2018). I couldn’t help but draw a parallel to my own parents’ lack of formal education, which was impacted by the turmoil in Europe while they were at the age of attending high school, and the potential improved outcomes for my siblings if they had been adopted out. Not that I’d want to rewrite history, but could my brother’s intelligence been improved if he’d been adopted?

The final detail in this mix of confounding factors is the age at formal adoption. In Kendler et al. (2015) this information was not available, but it was indicated that children were “adopted at a median age of 6 mo, with very few children adopted after 12 mo of age” (p. 4625). This is important since formative brain development of infants happens early. In terms of the impact of nurture, this is an important factor since it is a commonly known fact that brains develop early in life. Again, not that I want to rewrite history, I consider how different his life would have been should my brother have been adopted shortly after his birth. Who wouldn’t want the best for their brother who tormented them when growing up?

All joking aside, with this particular study and the insights gained from Willingham (2009) this nature-nurture debate has hit closer to home! If a 2:1 ratio between parental education levels and children’s intelligence is the one fact I’ve pulled from this research, I think our focus should be on improving adult education levels! Let’s ensure that everyone gets richer with the help of a strong education.

References

Kendler, K., Turkheimer, E., Ohlsson H., Sundquist J., & Sundquist K. (2015). Family environment and the malleability of cognitive ability: A Swedish national home-reared and adopted-away cosibling control study. Proceedings of the National Academy of Sciences of the United States of America, 112(15), 4612-4617.

Regalado, S. (2018, November). Critique of research article: “Family environment and the malleability of cognitive ability: A Swedish national home-reared and adopeted-away cosibling control study”. Personal Communication, D2L course submission.

Willingham, D. T. (2009). Why don’t Students Like School? A Cognitive Scientist answers questions about how the mind works and what it means for the classroom. San Francisco, CA: Jossey-Bass.