If IQ is a measure of g factor and you can't change g factor... Why do peer reviewed studies constantly and consistently find that IQ changes dramatically based on environmental factors?,(reply>), They don’t… unless you are talking about head trauma, poisons, strokes, dementia, and that sort of thing.<br>“Peer reviewed studies” that “consistently find that IQ changes dramatically based on environmental factors” only exist for downward changes…<br><br>We do know that parasites and malnutrition is bad for people’s brains so we know we can raise people’s IQ by eliminating those problems, at least if we do it early enough. It doesn’t seem to help much once people are adults. There have also been at least one sporadic case in the medical literature of someone who produced too little of certain neurotransmitters who was chronically depressed, sluggish, and slightly stupid who basically became normal after being put on antidepressants. It’s a real shame that antidepressants don’t usually have such a dramatic effect on IQ.