I usually have great self control, even when it comes to one of my biggest temptations – beautiful shoes. I can go months and months just window shopping, with hardly a twinge of pain when I leave without a new pair.

But all that goes out the window after a bad migraine. As ridiculous as it sounds, I could swear that I sometimes buy shoes by accident during my postdrome. It turns out there might be an explanation for that:

… chronic physical pain leaves people with a perpetual shortage of willpower because their minds are so depleted by the struggle to ignore the pain.

Some scientists think willpower is like a muscle that can get tired, rest, and be trained. Who knew?

Baumeister and Tierney lay out some of the evidence for this idea in Willpower: Rediscovering the Greatest Human Strength. As fascinating as the idea sounds, I don’t actually recommend the book. The interesting and useful bits are buried under a whole lot of annoying false buildup and fluff.