What is the most disturbing thing that you can think of?

Being trapped in a coffin under ground while alive

Being strung up my my testicles, having my teeth kicked out by a donkey, where then the teeth are collected, ground into a powder, then shoved down my anus, and having an M80 firecracker shoved down my urethra and detonated. All while being stung my an angry hornets' nest

Answer sweat and vasodilation;