This assumes that the number of times one can rotate before losing one's orientation is random. Presumably it is not only regular, but you might even get better as you practiced. Both of these would conspire to produce substantial autocorrelation in the generated series.
interesting discussion. but regarding 99%, I know of no environmental manipulation which can explain that much of individual differences. it's not just about reliability, it's also about explaining all the variance - two different things.
i see - so you're talking about gene x environment interactions. it's true this isn't accounted for in the analysis.
but i find it hard to believe that environmental effects of any sort could explain 99% of the variance that we see here, and I don't know how even a whole genome analysis could rule out GxE interactions. how exactly is that done?
i have trouble seeing how these comments apply to the content of the post - parenting influences are largely controlled (as you seem to indicate) and I don't see how these heritability estimates could reflect something unrelated to executive function. that's the whole point, they clearly have something to do with executive function. one would assume that something like appearance would show large unshared environment since kids dress differently, etc/
1) 99% is not unbelievably high, given that they used factor analysis to improve the reliability of the measurements
2) this doesn't preclude a) environmental influences that interact with genetic profiles nor b) environmental influences which act on the mean value of a twin-pair's score (the study's concerned with deviations from means within twin pairs).
You think that liPFC is involved in gain? An alternative is cue specification, which is consistent not only with the work purportedly showing a gain-like function in liPFC, but also with other work suggesting a role for liPFC in episodic retrieval.