“It's a thousand tiny impulses, building on one another. First you decide it's a good idea to check the oatmeal bin for bugs. Next you're going through all the canisters, and before you know it, you're wearing a hazmat suit and examining the frosted flakes for ground-up glass. Each action further enforces the obsessive-compulsive circuit. When the disease is full-blown, sufferers are firmly entrenched in the neural loops that make them repeat thoughts and actions over and over. In other words, your brain keeps getting back in line for the same carnival ride it didn't enjoy in the first place. You lose your sunglasses, you throw up on your shirt, and two minutes later you're back on the Whizzer. Wheeee.”