A reader writes:

I say this as a retired psychotherapist of many years. The reason we touch our lips is to see if we are still there. It is out of insecurity. The most basic first experience was oral contact with our mother. Our mouths were the first sensory experience that we had, was our first contact with the world. It is our most basic way of identifying ourselves and our existence. We are constantly insecure and anxious about a variety of things, mostly on a low relatively unimportant level. In the midst of interactions we check, by touching our mouths, to make sure we are still there, still ok.

It's a very minor thing, way in the background of your attention, like straightening in your chair to focus your attention a bit. Touching the mouth to confirm to yourself you are still here, ready to respond. Often when we are told something shocking or distressing, the first reaction is to reach for our mouths, often covering them with our hand. We press harder, based on the stress level. Yup, still here. Haven't disappeared yet. There is a sensuality associated with our mouths, eating is a pleasurable thing, tasting, etc. But that is not why people touch their mouths with their hands.

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