How artificial neural networks build their own learning machinery

As artificial intelligence becomes more powerful, its ability to handle humanlike tasks is undeniable. Artificial neural networks can learn to recognize images, use language or write computer code. Like the brain's circuits, they reorganize themselves as they learn, adjusting the strengths of their connections to improve their performance. The question for many neuroscientists is: What can these machine systems teach them about how the brain learns? And what kinds of models are likely to be the most informative?