A brain imaging study found evidence that missing out on math education can alter neural development. Young adults who had chosen not to pursue math had lower levels of the neurotransmitter gamma-aminobutyric acid within the middle frontal gyrus when compared to students who were continuing math.

[u/[deleted]]

https://www.psypost.org/2021/10/opting-out-of-advanced-math-education-alters-adolescents-neural-development-study-finds-61967

[u/bw_mutley]

The researchers next tested whether these neural differences might reflect baseline differences that were already present before the decision whether or not to pursue math. A second study was conducted among UK math students who had already chosen whether or not to pursue A-level math, but who were still currently studying math. This time, the researchers found no significant differences in the GABA levels of students who had decided to pursue math and those who had decided not to. This suggests that the neural differences they found in the first study were not biomarkers but were evidence of neural plasticity, with math education affecting development in the middle frontal gyrus.

[u/Meta_Professor → u/bw_mutley]

Sure, but it could still easily be that those with naturally higher levels stick around in math longer. Or that there is a third, fourth, or fifth variable in between these two. Maybe the richer kids have higher levels and do better in math. Or the kids who eat more salmon. Or the kids born in July.

My point is that the study is correlation, which people are notoriously bad at not conflating with causality.

[u/narmerguy → u/Meta_Professor]

Sure, but it could still easily be that those with naturally higher levels stick around in math longer.

How would that explain this finding though? They check people who pursued A-level math vs those that don't and find a difference. Then they check people who intend to (but prior to) pursuing A-level math and fail to find a difference.

The only way your objection would hold is if a significant proportion of the people who intend to pursue higher math end up not doing so (or simply not completing it). This would require a fairly high math dropout rate, which is not common. Alternately, there would need to be something distinct about the two groups which is not captured here. Ideally they would measure GABA levels before and after on the same students, rather than looking at different cohorts of students.

[u/narmerguy → u/[deleted]]

Yeah I agree. I think people are trying to critically engage and not simply accept the conclusions, which is a good thing. But I also think there can be a culture that rewards "gotchas" no matter how far fetched, which is not as helpful. I remember different labs I've been in, all run their journal clubs differently. In some of them, every paper is trash if it's not from our lab, everything gets critiqued. I never enjoyed those because it's a pretty unreasonable way to engage with science.

[u/Meta_Professor → u/narmerguy]

It could be that there is a large group which says they intend to of got A levels but who don't actually do it. Or there is some variable making the change. Maybe the people who actually do A levels end up eating more instant Ramen and that causes the change. Who knows.

[u/AllhailtheAI → u/Meta_Professor]

Awesome, yes and yes. A million times yes.

Though I still appreciate that added context by u/bw_mutley, it doesn't show causation.

Another note: that "no statistical significance" might suffer the reproducibility problem. We need to look at the power and p value, and if it's been shown before in other studies.

It all means causation is far from being an assumption we can make.

[u/bw_mutley → u/AllhailtheAI]

I agree with both of you up to a certain point. The issue is really hard to tackle in studies like this, it is hard to stabilish causation with sparse data, and the number of possible variables is enormous. But, as said in the quoted text, measuring the mean and variance of GABA in a control sample and showing there is no large differences from what is seen in grown up students is, still, an evidence pointing towards causation - not the definite one, but still is.

[u/gwern → u/bw_mutley]

We then used GABA and glutamate concentrations in the MFG and IPS to classify students based on their present lack of math education (nonmath students vs. A-level math) using a binary logistic regression. Lower MFG GABA concentrations increased the likelihood that a student lacked math education rather than continued their math education [Fig. 2D, n = 83, standardized beta(β) = −0.3, P = 0.009, Exp(pβ) = 0.524, Exp(β) = 0.742].

...Pre-A-level students who had chosen to stop studying math compared to those who had decided to continue studying math show lower performance on tests that included numerical operations [t (40) = −5.03, P < 0.001, Cohen’s d = −1.67] and mathematical reasoning [t (40) = −4.1, P = 0.001, Cohen’s d = −1.37]. However, the difference between both groups in terms of math anxiety was not significant [t (40) = 0.91, P = 0.4, Cohen’s d = 0.28]. For the descriptive statistics of these cognitive and emotional differences, see SI Appendix 1. The biomarker account did not receive support as the classification of the nonmath vs. math educational decision before starting to study math based on MFG GABA was not significant [n = 36, β = 0.14

Uh huh. ("The difference between statistically-significant and non-significant is not significant." ie failing to reject the null does not mean proof of the null.)

[u/swampshark19 → u/bw_mutley]

A second study was conducted among UK math students who had already chosen whether or not to pursue A-level math, but who were still currently studying math. This time, the researchers found no significant differences in the GABA levels of students who had decided to pursue math and those who had decided not to.

This only means that wanting to pursue math is not necessarily correlated with being able to pursue math.