The Dodgy IQ Game: Why the Test Itself Is Fundamentally Broken
The Dodgy IQ Game
Disclaimer: I usually write pretty casually here, but sometimes when something really gets my goat, I'll childishly pop out references just to make a strong point. This is one of those posts!
The Genetic Foundation of Intelligence
Someone I know has a thing for IQ. The idea of passing Mensa to be in the top 2% of the population was their absolute dream! In fact, after splashing out on a test, and then, one day saying, 'IQ is capped by racial genetics,' another disagreement began. Okay, I thought, yeah, people wouldn't exist, let alone think, without their genes, but I can't agree with our general intelligence having a prescribed ceiling height; I had to look into this stuff.
Let’s Start With Genes
Of course, genetics may well be our prime disposition for things, but how we nurture cognitive ability will always play a role in its development into real intelligence. So I've been looking up some meaty stuff and decided to have a crack at making this a tad more academically flavoured:
Genetics tells us our FOXP2 genes play a vital part in complex communication (Becker et al, 2018). We humans are rich with the gene, like bats, whales, dolphins but we regulate it especially for our complex speech and language - that's why you can read this post. A mutation or lack of FOXP2 is often linked to speech and language disorder. But, whenever people try new methods to overcome their disabling comminication problems that's also intelligence in action. This means intelligence goes deeper than just IQ.
The genetic contribution of our individual differences, or heritability makes perfect sense; it stands up to pro G factor arguments (the idea of intelligence being capped by IQ results). Sources like Plomin et al. (2016) say 50-80% of IQ variation come down to genetics. In other words, if height is about 80% heritable, but our average height has dramatically increased over many generations, is that ALL genetics? No. It's just better nutrition! The genes didn't change - the environment did. Narcissistic types will use IQ with a kind of reductive talk to distinguish themselves from others. My other blog here, explores how IQ test scores can brand people of faith. Should we be saying Christians are cognitively inferior to the Atheist because their IQ scores show a trend? We have to understand the figures.
Questions of Validity
For now let's consider adoptive children and also fraternal twins. Some twin studies are particularly useful at showing how identical twins raised apart have strikingly similar IQs, but many show differences (Plomin et al. 2016).
If I can play devil's advocate here by asking you to imagine one of those twins had a predisposition for bipolar disorder. Would a depressive episode during an IQ test be an environmental or genetic factor if the score is, say, too low? Bipolar states can easily disrupt our mental functioning in an IQ examination. No doubt, OCD has stolen test time with compulsions to overly re-check everything; need-based test tweaking is another component supporting an unsure result. It allows margin for error and room for doubt. About 1 in 4 US and UK citizens had mental health issues in both 2022 and 2024. This rough figure is static, remaining in the same ballpark as the Time to Change campaign which ended in 2021. This is around a quarter of the population who would be misrepresented in a standard IQ test. Have you ever seen an IQ test that offers a notch for notch handicap following a conditions individual severity? Psychiatrists don't detail the cognitive impairment of their individual outpatients; quality of life is the focus—it's poorly tracked.
On the same note, the genetic architecture of autism with its neuronal clusters, can actually reveal a much clearer gap between IQ and adaptive functioning or common intelligence. Studies followed high functioning autistic boys and scored them as average to above average, they did better than autistic girls. Of course, limited education, black and white thinking, oppositional defiance, and rigidity of thought are not helpful with flowering a developing mind with enough intelligence to navigate life with the same ease as neurotypicals—spikes or splinter skills are frequent in neurodivergence.
IQ testing has clearly not considered everyone's intelligence adequately.
Do fainting goats faint because of a genetic mutation, or is it because of the loud noise that startled them?
Education
That Bell Curve of the 90s
This is the crux of it. The need to feel superior over other ethnicities has resulted with studies like Herrnstein and Murray's The Bell Curve (1994) being celebrated. It promotes racial IQ differences mostly based on numeric data that meets their need.
Figures like the philosopher, Ned Block have criticised Herrnstein and Murray for oversimplifying intelligence and ignoring cultural bias in testing. Cold numbers alone are ignorant. Nisbett et al. (2012) argue that socioeconomic factors and historical inequality play a big role. Depending on place, time, candidate and tester, examinations can still be ill suited.
Before the Berlin Wall fell, why was there a consistent difference in IQ between East and West Germany of 5-10? It was not the Germanic 'race' but, obviously the inequality in socioeconomic standards. The scores eventually equalised as their economy did. We see the same in this classic controversial longitudinal adoption study. Black children raised by more fortunate non-black parents increased their IQ scores.
Yes, we know East Asian countries dominate the top IQ rankings; Japan and Taiwan are tied for first place, but they regularly push IQ tests in their educational practices.
Neuronal and Social Clusters
We have to be honest and accept there are genetic conditions specific to certain ethnicities. This proves genetic variation exists across populations, but that is illness and not racial intelligence. Can you think of any genetic conditions linked to higher IQ prevalence? Again, we have to say yes, neurodiversity, but does that always capture all-round intelligence? No.
Health-aware and more fortunate families across the west are more likely to see the signs of neurodivergence in their kids and get help, than those with health nihilism. We know many gifted children of this demographic gravitate towards bodies like Mensa. Others do not. The Mensa ADHD rate alone is 7.4% of members (IQ over 130)! All self-reported - that's nearly double the estimated general adult population rate!
Ethnicity Figures
Regarding ethnicity in the USA: We see a decent amount of Asian or Pacific Islander children have an ASD - prevalence of 38.2 per 1,000 children, many are high functioning.
White children have more ‘higher-functioning’ ASD with fewer affected with Intellectual Disability (ID).
Black children have a prevalence of 36.6 per 1,000. Unfortunately, numbers show a comparatively higher count of ID. Frequent misdiagnosis of behavioral disorder is uncovered in the data, and non-diverse evaluation led to fewer HF ASD black children being identified.
Scarr and Weinberg (1976) argued environmental factors override genetic predispositions, that is to say, intelligence can be wasted or lost in abject poverty or hardship. Cold numbers show IQ averages and who is being diagnosed with what - not the complex factors and social circumstances of life like in the 1980s Germany study.
Please, explain how racial IQ is benefitting anyone, given we don't fully understand intelligence yet.
Human brain scan
The Importance of Context: How Environment and Genetics Intersect
We touched on the boundary line separating genetics from environment, it can look quite blurred. For instance, Turkheimer et al. (2003) presented how the influence of genetics on IQ is moderated by such environmental factors. Yes, the paper says a bit about wealthier kids showing a higher heritability of impressive IQ, but instead, it's the impoverished kids from harsh or abusive backgrounds that are an overlooked detail: abuse-based cognitive issues are symptoms not the cause. It stems from the trauma of sensitive and intelligent individuals.
Intelligence from an evolutionary position is also environmental. Living north of Svalbard and The Congo both require types of intelligence not useful in France. We showcase our diverse resourcefulness and adaptive resilience even today. Let's be honest, do you think ancestral tribes of the frosty tundra ever had the opportunity to erect sheet metal plants or physics labs? Of course not, circumstance deals us the hand we get.
The ideal world provides every child an education, nourishment and safety, but that's why they're ideal worlds. Studies like Heckman (2006) and Marmot (2010) have informed Government how early interventions fight poverty, and health inequality are shown to boost cognitive potential. It seems to go unheeded.
The Need for a Nuanced Discussion
IQ tests don't capture all intelligences: emotional intelligence, creativity, social or strategic skills as well as common sense, they aren't measured. Sternberg (2004) stressed the importance of broader measures. US and UK education systems now favour more holistic approaches because they're thorough. Most UK courts and employers have dropped IQ testing. Ironically, even people with high IQ scores speak out against confining intelligence to a number.
Conclusion
The Flynn Effect supports the idea that IQ has significantly increased over the last century because of environmental factors, like improved nutrition, and increases in reasoning-based jobs and the role of education. It shows that we can improve upon our future IQ test results through learning and practicing how to answer the questions. Above all, the G factor can't be fixed given this fact and the existence of our brain's neuroplasticity!
Finally, sitting a test might involve applying your knowledge of formulas, theorems, problem-solving and reasoning, because knowledge is drawn from memory. Memory is definitely not untapped intelligence. In fact, throughout our evolutionary history progress came from failure, true grit, trial and error - hunting food was never closed with a one off, final and definite decision. Competitive students in countries that use IQ tests in education have real motivation to practice improving their scores (Flynn, 1987).
Ask Yourselves:
References
Becker, M. Devanna, P. Fisher, S, E. Vernes, S, C. (2018) Mapping of Human FOXP2 Enhancers Reveals Complex Regulation [Online] Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC5826363/
Flynn, J.R, (1987). The Mean IQ of Americans: Massive Gains 1932 to 1978. Psychological Bulletin.
Herrnstein, R. J, & Murray, C. (1994). The Bell Curve: Intelligence and Class Structure in American Life. Free Press.
Heckman, J. J. (2006). Skill formation and the economics of investing in disadvantaged children. Science, 1900-1902.
Nisbett, R. E, Aronson, J., Blair, C, Dickens, W., Flynn, J. R., Halpern, D. F, & Turkheimer, E. (2012). Intelligence: New findings and theoretical developments. American Psychologist, 130–159.
Marmot, M. (2010). Fair society, healthy lives: The Marmot Review. The Strategic Review of Health Inequalities in England post-2010. London: University College London.
Plomin, R, DeFries, J. C, Knopik, V. S, & Neiderhiser, J. M. (2016). Top 10 replicated findings from behavioral genetics. Perspectives on Psychological Science, 3–23.
Scarr, S, & Weinberg, R. A. (1976). IQ test performance of Black children adopted by White families. American Psychologist, 31, 726–739.
Sternberg, R. J. (2004). Culture and intelligence. American Psychologist, 59, 325–338.
Turkheimer, E., Haley, A, Waldron, M, D'Onofrio, B, & Gottesman, I. I. (2003). Socioeconomic status modifies heritability of IQ in young children. Psychological Science, 623–628.
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I agree with most of the article, like of course depression and mental illness can invalidate a test, I agree that IQ is 80% genetic. I just disagree with the claim the racial difference in iq is environmental. And also the article downplays iq.
ReplyDeletesince it is established there is a iq gap between racial groups it would be safe to assume it is also 80% genetic, unless there is evidence that it is 100% environmental. You mention the twin studies, which people always bring up but never read. The twin studies were when they got black and white children, very young, who were adopted into high iq wealthy white families. They tested the IQ’s of these kids when they were 7. This showed that the average IQ of adopted white kids was around 106, and black kids were around 106 as well. People bring this up because it seems to show the racial iq gap is environmental and not genetic. But people always conveniently leave out the fact that a follow up study was conducted when the kids were 17, not 7, and the black kids iq reverted down to 89, and white to around 100 or so. The genetics won in the end, this is well established as the increased heritability of IQ with age. The twin studies actually demonstrate that racial gap in IQ is genetic. Since when they were raised in the same environment iq was lower. “But why was the IQ at age 7 for black kids higher than at 17?” Because IQ is indeed affected by the environment, and this effect is most pronounced in development, childhood. Spend any time in cognitive testing communities and anecdotes abound of kids with very high iq like160IQ, who grow up to have an IQ much lower. Testing a 7 year old is just bad science, it’s too young to give meaningful results. Age 11 would have been better, like what Scotland did. Once you escape childhood iq is much less environmental and much less subject to change, with the IQ at 11 correlating highly with adult and even elderly IQ. But not at 7.
The article is downplays just how important IQ is, it is a predictor for: average salary, manager rated job performance, how good of a soldier you are (google project 100,000), and grades. Yes there is a study showing a-levels were a better predictor for medical careers. Cool. There are bigger studies, and meta analyses, that show IQ to be a good predictor for educational attainment and social status. And so many other things.
Iq isn’t used much anymore because black people got angry that they couldn’t get jobs that required high iq so they filed a lawsuit and got iq testing banned. Tho iq testing still kinda exists it’s just renamed apititute tests.
Cheers, respectfully, I see you've not commented on the Germany study, Flynn Effect, and neurodiversity evidence. I guess those are the areas you agree. However, you might have misinterpreted that particular study I used to be fair. Briefly, at 17, adopted black children still scored above the national black average, not 'at' it. It reflects accumulated 'environmental effects' which aren't always very fair. This doesn't prove genetics. It would reflect the environmental factors, those associated pros/cons. Adoption doesn't erase every environmental problem from a persons background.
DeleteYour '80% genetic' claim, isn't quite what the blogpost says: heritability changes with environment, like the Berlin Wall study. In poor environments, heritability drops. Is it right to apply one heritability figure universally? Look, hey ho, easy mistake though. No big. Always doing it. Heres a quick link: https://en.wikipedia.org/wiki/Heritability_of_IQ
I doubt IQ testing was 'banned because black people got angry'. The tests were gradually phased out, after the 11 plus, wouldn't've sat well with the Equality act 2010 either, protected characteristics and shit. Improved multi disciplinary team assessments replaced IQ tests in education, prisons and law etc.