Is someone's IQ stable during life or may increase or decrease?!
Question: how?
Answers: how?
It goes up as you get older and once your past middle age it goes down. That's called cognitive decline.
However, training exercises can make it go up! Old people, with exercise, can literally make their brain younger by about 10 years or more with consistent practice. There is proven scientific evidence for this. There's software on the internet for just such a thing.
It usually goes up a few points as you age. It could go down if you had brain damage.
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