The human brain is not finished at 18: the prefrontal cortex that handles control and planning matures only around 25, while the emotional regions ripen at puberty, and that phase lag explains much of teenage impulsiveness. At the other end of life, synapses explode in number during the first two years and are then pruned back through childhood to leave a leaner network. Height surges twice, in infancy and at puberty, then stops for good once the growth plates close.
The human brain is not finished at 18: the prefrontal cortex that handles control and planning matures only around 25, while the emotional regions ripen at puberty, and that phase lag explains much of teenage impulsiveness. At the other end of life, synapses explode in number during the first two years and are then pruned back through childhood to leave a leaner network. Height surges twice, in infancy and at puberty, then stops for good once the growth plates close.
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