In my business class we read an article about emotional contagion: the tendency to automatically mimic and synchronize expressions, vocalizations, postures, and movements with those of another person's and, consequently, to converge emotionally.
The idea is basically that there exist emotion families, and these come in packages that we communicate to other people. It is comprised of several components including those mentioned above. The amazing thing about this is how quickly it gets communicated, and all of it is pretty much unconscious and automatic.
We've all experienced to a certain degree, right? A friend/spouse/someone else comes in the door all flustered because he/she just got towed and now has to go get the car and pay the fine. You start reacting emotionally, but the thing is you don't realize just how much you are doing so. You mimic conversation patterns, use the same words as the other person. Your facial expressions mirror that of your flustered friend, and from moment to moment you 'catch' another person's emotions.
I actually saw this earlier this week when I was checking out at Walmart. I'm about to finish up my transaction when out of the corner of my eye I notice that the person behind me tries to run around her cart to catch her child that fell backwards out of the seat. She doesn't make it in time. Not only do I hear the thud of the girl's head hit the ground (is there a worse sound than a skull crashing onto the ground?), but I actually felt the impact. The mom is trying to comfort the little girl who is about 3 years old or so, but the 1 year old still in the cart begins sobbing because he senses the commotion and all of the reactions around him even though nothing actually happened to him.
Whoever is feeling the stronger feelings usually communicates those to the recipients around him/her, and this is kind of something innate that people interpret quickly and also quite accurately. A lot of times we think that we can't interpret what others around us are feeling, but where this information becomes most useful is in just asking yourself what it is that you're feeling. Upon interacting with another person, if you start noticing that your mood is altered, then it's probably a safe bet that there is some transference going on.
I thought this whole thing was kind of interesting, and as I've thought about it recently, there is so much that just goes into reading the people around you. There are certain people that you breed a strong familiarity with over time and their cues become obvious. I think with different people we have filters that allow that emotion transference to pass through in varying degrees. The people we're closest to probably don't even have a filter. We just absorb and internalize their feelings immediately.
I guess I've just thought a lot about this in my interactions this week, with certain friends that I know really well to others that I'm only just recently becoming acquainted with. I wish there were some way of just learning another person's cues right away, but at the same time it's kind of fun figuring people out.