Hello WillowElf: This is something the Skeezyks has had a problem with. I don't know how you stop. Hopefully the article CANDC linked you to was helpful. I stopped once I had managed to do myself permanent physical harm. There are multiple dangers lurking within this practice. Concussion is one. But also Meniere's Disease & tinnitus (ringing in the ears) & also eye problems such as detached retinas. So I would really like to encourage you to seek the help you need in order to overcome your self-harming. I send warm thoughts your way with the hope that you will be able to find healing.