Who's had a concussion?

Just curious how many people here have had a concussion. Seems like there's a pretty strong connection to head injuries and DP. I know for me, looking back on my life, my DP really started after suffering a concussion at age 15. I also know of another person I met recently who had a similar story, hitting his head then smoking weed afterwords and getting severe DP. If you search "concussion" there's quite a few posts here about people with similar stories. Not saying DP is a result of concussions exclusively, but perhaps there could be a connection between concussions and drugs and those already predisposed based on genetics or upbringing...