Put me in a cold room and wrap me in a blanket and I’ll fall asleep.

Same thing happens in airplanes after they shut the door. Before the plane even takes off, and even on a full night’s sleep, I begin to doze.

Often, when I see a sign for “Bathroom,” I find I need to use the facilities. Sometimes desperately. Even if I didn’t have the slightest need prior to seeing the sign.

We all have our triggers.

Remember Pavlov’s research on digestion? While undertaking other experiments on dogs, Pavlov noticed that they salivated at the sight of his research assistants’ lab coats. (Typically, the assistants brought them food.) Then he set a metronome at mealtime and found that, after a while, the dogs would salivate to the metronome—food or no food.

If ever you feel too superior over your pets, think about your similarity to Pavlov’s dogs.

Instincts drive us.

You yawn when someone else in eyesight does. You crave burgers after you see them spinning around a camera on television, sizzling. You hear the pop of a beer top and feel thirst.

Hence the difficulty, as I mentioned in a previous post, for addicts of any kind to kick their habits when plunked into familiar environments: Oodles of triggers, from friends to routes home from work. Triggers generate unconscious reactions—even unwelcome ones. (Ah, how often I plan to get work done on airplanes, yet can’t seem to keep my eyes open.)

What are your triggers?