What is Intelligence?
Smart. Clever. Sharp. Three things that anyone at any age aspires to be. But does your intelligence depend on your genetics? Intelligence is a term used to describe cognitive ability, performance, functioning, and emotional wisdom. It can also include the ability to learn and adapt to changing environment(s) and experiences.
Why is it Controversial?
As a human being, your intelligence can be strongly influenced by your environment and genetics, which are a set of traits passed down to you by your parents. It is tough to distinguish between environmental and genetic influences on intelligence since they go hand in hand with each other. It is also hard to figure out which areas of the brain are responsible for specific features or dimensions of intelligence. Such a discussion can lead this topic to a different realm, which might also be very controversial.
How do the environment and Socioeconomic status (SES) play a role?
A question one may ask is, to what extent does the environmental and socioeconomic status of a country play a part in the average intelligence of its citizens? “In 2014, the high school dropout rate among persons 16–24 years old was highest in low-income families (11.6 percent) as compared to high-income families” (APA 2017)
Less Developed Countries (LDC) which are more likely to have a low-SES background might not be in a position to consider education as an important factor in their citizens’ lives. Owing to insufficient funding, their schools lack new, reliable, and accurate information and technical expertise which could have been beneficial for a better lifestyle. They might, therefore, focus on jobs that can generate expeditious money. In high-income families of More Developed Countries (MDCs), the dropout rates are significantly lower. They are 8 times more likely to obtain a bachelor’s degree by age 24 as compared to individuals from the lowest family income quartile. (APA 2017) This can be caused by their stable financial backgrounds, more resources(good schools, guidance counselors, etc), and familial experience with higher education.
All these things can influence one’s brain to reach its fullest potential. There still might be people who live in relatively the same living situations, yet perform very differently in terms of their intelligence.
How does Genetics play a role?
Genetics can vary a lot with people, and so can intelligence. Is this a coincidence or a fact? Scientists have been acquiring more knowledge about intelligence and how it manipulates the brain. Recently, they have been comparing and looking into DNA (the genetic code) and intelligence to see if they are related.
At least a third of the approximately 20,000 genes that comprise the human genome are active (expressed) primarily in the brain. (Brain Basics: Genes at Work in the Brain | National Institute of Neurological Disorders and Stroke, 2010) These can contribute a lot to the development and functioning of the brain or the cognitive skills which can include the way we move, think, feel, and behave. This is one of the ways intelligence is measured.
Intelligence is highly heritable, but what differentiates intelligence from person to person is that it is subject to change. This can change over the age of a person or the malleability, which is the environment.
Can environment and Genetics both play a role?
Environment and genetics play a big role in the intelligence of the human brain which can include their living situation, parenting, education, healthcare, and nutrition. They are both factors that can not be controlled by anyone.
A study conducted in London with more than 11,000 pairs of identical and nonidentical twins born in the United Kingdom researched how well each individual scored in the GCSE (General Certificate of Secondary Education). As for the results, “ In all, about 62% of the individual differences in academic achievement—at least when it came to GCSE scores—could be attributed to genetic factors” ( William 2014).
If this experiment had taken place in different countries, especially less-developed countries, the results would have been very different because everyone does not have equal access to education and has a different drive to learn.
What is Intelligence Determined by?
In conclusion, human intelligence can be hereditary, but it can change or mold its way as humans grow and their environment changes with them, causing them to differ from other humans.
References
American Psychological Association. (2017). Education and Socioeconomic Status. American Psychological Association.
https://www.apa.org/pi/ses/resources/publications/education
Plomin, R., & von Stumm, S. (2018). The new genetics of intelligence. Nature Reviews Genetics, 19(3), 148–159.
https://doi.org/10.1038/nrg.2017.104
Williams, S. (2014, October 6). Genes don’t just influence your IQ—they determine how well you do in school. Www.science.org.
https://www.science.org/content/article/genes-dont-just-influence-your-iq-they-determine-how-well-you-do-school
U.S. Department of Health and Human Services. (n.d.). Brain basics: Genes at work in the brain. National Institute of Neurological Disorders and Stroke.
https://www.ninds.nih.gov/health-information/patient-caregiver-education/brain-basics-genes-work-brain
