(Fast Company) — The essence of affection. The cuddle chemical. In other words, oxytocin. This hormone, produced daily by your brain and mine, is the reason I’m on my back, trying to remain perfectly still inside a magnetic-resonance-imaging machine secreted in the basement of a cheerless building at the California Institute of Technology. Even though I am cocooned by earplugs and noise-cancellation headphones, it’s freakishly loud in here, a mix of jackhammer pulses and a hurricane whoosh of air. In other words, it’s your typical MRI experience — save for the Apple laptop bolted a couple of feet above my head, the mouse on my chest, and the unbearably sad video playing on the MacBook screen.