Re: What Are the Race Deniers Denying?

Bryant (
15 Oct 1996 19:41:58 -0600

[Adding sci.psychology.personality to encourage psychometricians' comments.]

In article <540ejq$>, Bryant <> wrote:
>>>What is highly debatable is whether the relationship is causal (big brains
>>>'causing' high IQ scores).

Rushton did a review of the evidence on brain size and drew very
different conclusions than I have drawn. There are now folks in two
parts of the country looking at whether developmental instability and brain
size correlate per a "stress" explanation of the IQ/brain size correlation.

I'd bet money that they find a correlation between prenatal/early
developmental stress and small brains.

I really don't think small brains are causally related to low IQ--I think
they both correlate with and are caused by developmental perturbations.

Environmental lead exposure alone could explain why impoverished peoples
have lower cognitive performance scores. Interestingly, the improvement
in the lower end of the IQ distribution in recent decades in the West
parallels the adoption of programs like WIC and school lunches.

The GOP may provide us with a natural experiment in the role of
environmental protection, clean water, welfare, and prenatal medical care
for the poor in improving human brain development.

At any rate, Rushton's review is referenced in this msg he sent to the
Darwin listserv when the topic was being discussed there:

> Empirically speaking it is almost indisputable that there is a
> significant positive relation between brain size and IQ. It is as
> verifiable a relationship as is to be found in the behavioral
> sciences. If anyone wants a copy of my review paper of this literature
> that appeared in the March 1996 issue of Psychonomic Bulletin and Review
> (vol 3, 21-36) please send your snail mail address to me (J. P. Rushton):