This article is the second in a series about using technology to overcome the most primal challenges to humanity: disease, aging and death.
When I taught Introduction to Cognitive Science at the University of California, Los Angeles, I put the following thought experiment to my students: Imagine that we could study a single neuron in your brain so well that we know everything about it. We know how it reacts to signals from other neurons, we know how it responds to neurotransmitters and hormones. We know exactly how it affects the rest of your brain and body. And with that knowledge, we build a tiny artificial imitation of that one neuron, and we replace the original neuron with our imitation. Nothing is different about how your body or brain works: as far as everything else in your body is concerned, nothing has changed.