Can't you add something witty like, "I have crashed many times without a helmet and I am proof it didn't leave any lasting effects." :)
OK,, you asked.........
I went thru a brick wall at 98mph back in 1978. If I didn't have my helmet on my brain would have been sucked out of my skull where the concrete wore a hole thru it, I guess. The road rash is another story. as is the rain room, silvadene, etc. etc.
I was run over by 5 guys from Iowa and my helmet had nothing to do with it. But it came off real quick when it got down to hand to hand.
I used my helmet a few times to correct unruly individuals.
A helmet will help you survive a basball bat attack.
I wear one when I ride sometimes too. It holds my do-rag on my head and keeps me from worrying about it above 75mph. :-)
Helmets have a purpose! And it's many!
Thank you. Carry on.