From: Timothy Bates <firstname.lastname@example.org>
Date: Monday, June 14, 1999 4:56 AM
>>>several researchers believe that IQ simply reflects brain "health"
>>>- that IQ 140 means nothing wrong, and less than
>>>that is the sum of all things that have not gone wrong.
>Daniel Ust asked
>> Which researchers believe this? And, much more importantly, why?
>At the 1997 ISSID (international society for the study of individual
>differences conference in Aarhus, Denmark), Arthur Jensen and others were
>discussing the genetics of intelligence, and Jeffrey Gray suggested that
>they are likely to look like a scree-plot (a term from factor analysis
>describes the relative importance of latent variables) which is very flat
>i.e., you need many many genes to explain very much of the variance. these
>genes, then will be for all sorts of "unintelligent" things like insulin
>control, blood carrying capacity, APO E4, etc etc etc. In this sense, a
>bright person has more than average numbers of the more efficient allelles
>at each of these low-level function loci.
That reduces to one person not several.:) But even so, thanks for the explanation.
I'd originally thought, picking up the discussion with your email as my computer was down until yesterday, that by "brain 'health'" you meant something possibly but not exclusively nongenetic. We need a model of what optimal health is for the brain and to see how this ties in with intelligence. My gut feeling is an unhealthy brain would lead to less intelligence, BUT what of epileptics (unhealthy brains, no?) such as Dostoyevsky? Are they counterexamples? Or could it be, if your (Gray's?) hunch is correct that Dostoyevsky, etc. would have been even smarter had they not had epilepsy? Or perhaps epilepsy might be different in this respect -- i.e., it might not have much to do with intelligence whereas other aspects of brain health might.
My interest right now would be in finding ways to overcome any genetic limits on intelligence in the short run -- viz., before we get all this groovy tech the future will provide.:)