The first time, I did not know what was coming. They operated on bones in my foot. Gave me a spinal block. When it wore off, they asked me to walk — on crutches, on the foot that had just been cut open. I made it a few steps. And then the world went black. Not metaphorically. I literally fainted. From pain. That was surgery one. There were three. And there is a fourth I need — and cannot make myself do. It has to do with a specific molecule in the neurons of my spinal cord. Once you understand what that molecule does, the fact that I cannot walk back into that operating theatre will make complete neurological sense. It is not a failure of courage. It is a consequence of learning.

I have always had a lot of fears. And since a young age I have been adamant about overcoming them. Not tiptoeing around them. Collecting them. Every time I collect one — every time I do the thing and survive it — something happens that still astounds me. How easy the second time is. How there is almost literally no stopping me. I always thought this was a mindset. It is not a mindset. It is fear extinction — and the female brain is specifically, hormonally primed for it at particular points in the cycle. Here is the science behind the thing that has helped me most.