Wow man, interesting and well written post. Trans-humanism, to me, is a scary concept. Although I'm not that well versed on the topic, something about it just seems inherently wrong. I once heard or read a quote that rang something like "all major technological advancements are first merited on their ability to be used as weapons". Although I can't as eloquently relate it as I originally heard it, that's the gist of it.
The point you raise of selective hearing as an example of evolution and neuroplasticity is actually fascinating.
The only real thing I can add is that it becomes increasingly difficult to stimulate children at school because of technology. A textbook lesson, with a vew videos just cannot match sitting infront of an LCD screen watching a movie, playing games on an i-pad and listening to music through earphones on an iphone. Children seem to be overstimulated and we will see how it effects the millenials in a few years time.
Keep up the good work