Interesting things that make me wonder about the validity of both IQ but also the Flynn effect, and if they are valid, the implications are weird. We saw steady significant increases in non-verbal IQ areas by about half a standard deviation, but verbal IQ apparently was not ever significantly effected. There have been reports about drops in IQ about the most developed nations since the mid-1990s, but even Flynn’s own research indicated that the trend was down in the UK and he blamed educational programs. It seems similar trends have happened in the US. It’s funny because I have cited the Flynn effect as proof for environmental and educational inputs on IQ but seems that there is a limit and even at a certain point, things actually go backwards in the most developed nations.
This, by the way, indicates that education reforms in the US and UK may have actually had negative “Intelligence” effects. Not just educational effects. Even if they are not the source–and I actually I do think the larger problems most likely are to be cultural and economic–they have relatively no effect. Flynn himself says that nutrition cannot be the explanatory source anymore.
it has been noted that “underdeveloped” nations do not well on the IQ tests, and there is generally understanding of some cultural bias there. This is probably the case, but the Flynn DOES apply in those countries if one sees long periods of relative piece.
IQ is weird.
Flynn, J. R. (2009). “Requiem for nutrition as the cause of IQ gains: Raven’s gains in Britain 1938–2008”. Economics & Human Biology 7: 18–27.
Teasdale TW, Owen DR (2008). “Secular declines in cognitive test scores: A reversal of the Flynn Effect” (PDF). Intelligence 36 (2): 121–6.
Gray, Richard (February 7, 2009). “British teenagers have lower IQs than their counterparts did 30 years ago”. London: The Telegraph.