Ha, the site said that heavy music is disturbing to the nervous system.
By "disturbing", they probably mean that it actually causes thought? From my understanding, thought outside of the established norm can be disturbing.
It also mentions that it causes stress? And stress is a factor created by conflict. People need conflict. Constructive conflict. Why else do kids get caught up in little things, like when you accidentally scuff their new Reeboks or K-Swiss?