The one to rule them all — Serotonin and the hidden bias in schools

Most people tend to think academic success is mostly determined by IQ. This is utterly wrong. Of course, academic success is determined by IQ, it is just not the most important factor. As a teacher, I have seen many underperformers, bright kids who dropped out of school or barely managed to finish their final exams. I have seen overperformers too, teens who would get up at 5 am on Saturday to cram from an exam on Monday and teen who would study so much for the final exams that they put on ten pounds of weight during the course of their studies.

So what is more important than IQ in predicting academic success? In the Big 5 personality inventory, one trait sticks out big time: conscientiousness. Kids with higher levels of conscientiousness display the following sub-traits:

These are the kids who are (almost) every teacher’s dream come true. Some of these kids even enjoy school. And these are the kids who finish high school with good grades, naturally. Who would disagree that they don’t deserve it? I, as a teacher, would not. Of course, it is fair that the hard-working kids get good grades, after all, hard work is what will count later on in their jobs as well, merely being intelligent isn’t good enough.

However, if we dig deeper, there is something odd here. I have argued that the above traits have evolved as a bundle of traits that served early farmers well an that might have been driven by higher levels of serotonin. So, these students might be just “lucky” enough to have inherited the right serotonin genes for school??? Serotonin promotes Stability and Stability represents the shared variance of Conscientiousness, Agreeableness, and low Neuroticism (). Based on these traits it is not hard to see how students high in serotonin display all of the above characteristics.

What about the other students who do not show these traits, like disruptive or ADHD students? These students are more dominated by dopamine? Does that mean that they worse learners?

Dopamine facilitates exploration, approach, learning, and cognitive flexibility in response to unexpected rewards and cues indicative of the possibility of reward. ()

No. They are more flexible learners. One could argue even better learners, just not in a school setting. High dopamine makes explorative learners more quickly bored with rote learning and sitting still for hours. These are the kids that are often sarcastically referred to as the “creative kids”, but this is what they really are. And of course, they perform worse than the high serotonin kids in most cases: years of boredom, inattention, neglected homework and low motivation take their toll. In some cases gifted kids get through school with average grade because they are intelligent enough, in some cases, they drop out. As you can see in the table below J (high serotonin) types completely dominate GPA scores. With ACT (tests for which students can’t really prepare) the pattern is at least partially reversed: it is dominated by two P (explorative, high dopamine) types and the P types often fare better than their corresponding J types (e.g. ISTP better than ISTJ, ISFP better than ISFJ, etc.).

So, which traits do the gifted, highly intelligent kids have? I have argued that they have typically hunter-gatherer, traits, i.e. they are highly egalitarian (dislike authority and therefore often get in trouble in school), they are out-group social (not identifying with and conform to any group and might therefore easily become outsiders) and they often have poor focus on rote learning, but hyperfocus when they are interested. Their dominant trait in the Big 5 inventory is “openness”, which is the only personality trait significantly correlated with IQ.

Ironically, the traits openness alone, even though significantly correlated with IQ, does not have a strong effect on school performance, as can be seen in the GPA scores (ENTJ best-performing personality profile vs ENFP worst-performing profile). The best performance at school is predicted by high conscientiousness and high openness (NJ in Myers-Briggs) combined, as can be seen from the average GPA levels in the table). High openness and low conscientiousness (NP) has relatively poor performance. It is not a coincidence that low conscientiousness and high openness are also somewhat predictive for . It was Thom Hartmann who actually first proposed a connection between ADHD and hunter minds.

By valuing orderliness and compliance (conscientiousness) higher than creativity (explorative and openness) schools have an inherent bias against creative students. The majority of creative scientists (Darwin, Einstein, Richard Feynman, etc.) and creative artists (Van Gogh, Picasso, Shakespeare, Orwell, etc.) belonged to the low-conscientious, high open profile. Consequently, you will find almost no Nobel Laureates who actually enjoyed schoo l.

Sir Ken Robinson’s TED Talk Do schools kill creativity? Is a warning that schools do indeed kill creativity. They definitely kill curiosity, not only in hunter-gatherer children but in all children. And they actively filter out the highly creative ones. Unfortunately for schools and teacher, those are the ones that do not fit easily into a school system based on rigorous rules and rote learning. For parents of such children, the best advice is to homeschool if possible or to look for alternative schools, such a Montessori school. Maria Montessori was of the low consciousness/high openness hunter-gatherer profile herself and understood that at least certain kids needed a different type of schooling.

Originally published at on April 11, 2020.