21.   Thus, the brain of a child appears to be more sensitive than the adult brain to the effect of low blood sugar.

22.   Until then, scientists believed that the adult brain did not produce new neurons because the brain had no cells that could generate them.

23.   When he tried to push the notion that the adult brain in animals and humans could potentially form new neurons, colleagues dismissed the notion as borderline fantasy.

24.   But a series of recent discoveries uncovered that the adult brain is remarkably more flexible.

25.   For generations, scientific dogma held that the adult brain cannot repair itself, because it lacks stem cells.

26.   Recently, scientists found that adult brains do indeed harbor stem cells, although their exact function is still a mystery.