Part 1 of 2 about the overlap between social and physical perception.
Those heartwarming touches can give us a warm feeling inside, and help us warm up to someone we don’t know well. On the other hand, a cold-hearted person will leave us cold, and if you give people the cold shoulder too often your significant other might get cold feet about marrying you. Fancy figures of speech, all, and perhaps not just pulled from the ether. We may describe positive social interactions this way because positive interactions really do make us warmer — and by contrast, negative interactions may make us feel colder.
This, at least, is the claim of an article from Psychological Science that placed 20 young adults in a brain scanner while they held onto a ball, held onto a warm heating pad, read factual messages from people they were close to (e.g., “I have known you for 10 years”) or read loving messages from those same people (e.g., “I love you more than anything in the world”). Holding a warm physical object not only led these volunteers to report that they felt warmer, but also that they felt more connected to other people; and reading a loving message not only meant more social connection, but also a greater sensation of warmth.
But it that warmth really about temperature, or is it about the colorful metaphors in our language? Although the precise wording of the questions isn’t given, we do know that responses about warmth in the absence of a physical object were phrased as “how warm [participants felt] after reading these messages”, so the question was phrased differently than it was when they were asked how warm the ball or the heating pack were. The volunteers might have interpreted “warm” as referring to a physical temperature when it was about an object, but as referring to a more intangible, emotional “warmness” when it was about those messages — the same way we interpret “wave” as the motion of the ocean or the motion of our hands depending on our context, without having to think about it. The nearly-identical averages for social connectedness and “warmth” after reading messages certainly leave room to wonder if volunteers are drawing on the same social feelings for both. So does a slight skepticism that people would really feel physically warmer after reading a loving message than holding an actual warm object, short of some serious blushing action.
This is where the brain comes in. All of these events took place in a magnetic resonance imager (MRI), which allowed the researchers to determine which regions of the brain were involved with both holding a warm pack and reading a loving message (but not with holding a ball or reading a factual message). Two brain regions stood out: the ventral striatum, part of our reward center and linked to our relationships (particularly love and sexual attraction); and the insula, linked to self-awareness of the body (including the perception of temperature) and emotional experience. The similarity in activity in these two brain regions hints at the possibility that the close connection between physical and emotional warmth is not a result of our colorful linguistic expressions, but a source for them.
The notion that social “warmth” and physical warmth are strongly connected is not a new one, and the corresponding advice to have people hold a hot cup of coffee if you want them to like you was revealed six years ago, but now we are seeing that it is not an unconscious play on words, but an unconscious interconnection resulting from brain regions playing double-duty as they help us interpret the world. An as we will see next week, this has some interesting implications for just what you should do when you’ve been given the cold shoulder.
Inagaki T.K., & Eisenberger, N.I. (2013). Shared neural mechanisms underlying social warmth and physical warmth. Psychological Science, 24 (11), 2272-2280. PMID: 24048423