I learned a new expression today, emotional contagion. I thought it sounded like a "misery loves company" kind of thing, but it turns out it is more related to unconsciously picking up on emotional cues via the eyes.
Officially, Emotional contagion is the tendency for two individuals to emotionally converge.
Still a bit confused? Me too, until I read research done by Univ. of Tennessee, Assistant Professor, Garriy Shteynberg, Ph.D. on the "psychological impact shared attention (also referred to as shared experience) has on culture and the mind." They basically study how shared attention affects another person's memory, emotion, and goals.
Christine Fawcett, Ph.D., of Uppsala University, Sweden studies emotional contagion by recording the changing a person's pupil size in response to seeing another person’s pupils dilate or contract. Working with 6-9 month-old babies, Fawcett's team showed infants black circles of different sizes designed to look like pupils. They recorded how the infants’ own pupil sizes reacted to these. and also showed the infants images of black squares as a control.
Their results were not super surprising (i.e. babies pick up on your mood), but the fact that they did not respond to the different sized black squares was interesting.
So if you subscibe to the old saying, "the eyes are windows of the soul" you might be closer to correct than you thought. Go science!