I assume many of you have had the same experience. You are looking into someone's eyes for a longer period of time and gradually the face of that person starts to disappear, as if you were being hypnotized or something. It's almost a bit like opening a door and surrendering
I usually have to smile in such a situation...
I don't know if it is related, but I can hardly imagine the faces of my family. There are general representations of their entire personae in my memory, but I might not recognize them if they stood before me today, especially in an unusual environment where I did not expect them.
On the other hand there are some people who are not close to me, but whose faces I remember very precisely.