Submitted by EchoTwice t3_z4bjpb in askscience
I've read about studies showing that during adolescence a child's IQ can increase or decrease by up to 15 points.
What causes this? And why is it set in stone when they become adults? Is it possible for a child that lost or gained intelligence when they were teenagers to revert to their base levels? Is it caused by epigenetics affecting the genes that placed them at their base level of intelligence?