“It’s exciting to show that the gap isn’t written in the stars”

As the expected chorus of incautious praise mounts in response to news of a forthcoming report by James Flynn  and company purporting to show a highly significant 4 to 7 point narrowing of the Black/White IQ gap over (roughly) the past 30 years, the stalwart brainforce at Gene Expression outlines some preliminary bases for skepticism.  Noting that "the gap between white and black children does indeed seem to be
decreasing over time," GNXP contributor Darth Quixote (who is well versed in the relevant literature) makes the important point  that the same trend does not hold for adult IQ.  While this may not seem significant at a glance, the potential  hitch, thus observed, arises from the long established finding that "the correlation between genotypic and phenotypic IQ increases with age."   And regression to the mean is a bitch.

Keep in mind the hope once attached to early rounds of intervention studies showing that early boosts in IQ tend to fade as people grow into their genes (pun semi-intended).  While Flynn has fashioned his findings after a meta-analytic rather than experimentally longitudinal review of test data, it remains likely that the observed gap-narrowing trends will prove similarly short-lived as the effects of wide-scale youth intervention are offset by the leveling effect of more genetically weighted adult returns. And of course, this isn’t the only criticism raised in objection to Flynn’s report, which is why Arthur Jensen and Phil Rushton’s forthcoming rejoinder will merit close attention. But genetic regression does strike me as potentially devastating.  Time, as always, will tell.      

Simply stated, the history of IQ research advises that caution should always precede celebration. Still, I suspect there may yet be reason to indulge in some guarded optimism about the big picture, and for this Flynn deserves some incidental credit. Regardless of whether the racial IQ gap is truly narrowing in any significant measure, it defies credulity to believe that the cumulative effect of a half century of nutritional and educational intervention — to say nothing of the less quantifiable (memetic?) benefits attributable to media-facilitated cultural immersion — shouldn’t manifest in some broadly observable cultural benefits for those at the greatest disadvantage.  While I tend to believe that the decade-long decline in violent crime is largely explained by higher incarceration rates, who’s to say that the cognitive effects of wide-scale youth intervention — even if such effects prove to be temporary — couldn’t play some complimentary role?  I don’t know of any evidence for or against such a possibility, but in the absence of a full-scale nootropic revolution, here’s to hoping.    

And for that matter, here’s to James Flynn. As the scholar who famously documented the  still controversial secular increase in IQ (commonly known as the"Flynn Effect"), the University of Otago political science professor has always struck me as a solid guy with a valuable bias.  While other scholars assume it’s infra dig to engage in informed debate with researchers who argue for intractable differences in aggregate cognitive abilities among racial groups, Flynn has always been there, slumming over the psychometric data in good faith and turning out enough original work to keep the hereditarians on their toes. Whether his latest volley stands to scrutiny, his efforts have consistently added value to the debate.  In this important respect, Flynn stands in admirable contradistinction to the late Stephen Jay Gould, who, for all his public honors,  never really played fair.