The human brain is a wonder of the universe, but our understanding of it can seem contradictory, says Steven Jay Fogel, author of the new book, "Your Mind Is What Your Brain Does for a Living.“ On the one hand, we’re often told of those crucial years that our brain develops in childhood, when we’re rapidly progressing in development of our language and other skills, and our preadolescent and teenage years, when our brains undergo a sort of second Big Bang of learning,” says Fogel.