Over the summer, I was a research assistant at the University of Chicago Booth School of Business where I ran experiments on judgements and decision making. One of those experiments explored the 10/5 rule – one of many hospitality principles. This rule suggests that when you’re 10 feet away from someone you smile and make direct eye contact. And when you’re 5 feet away from someone you offer a greeting (i.e. waving your hand) gesture. This experiment split the 10/5 rule in half and examined the amount of interactions participants made depending on whether they used eye contact and smiled at 10 feet or eye contact and used a greeting gesture at 5 feet. This made me think about real-life implications. If I walk around smiling at everyone that crosses my path, am I going to be happier? Are they going to be happier? Are we going to put out a positive energy into the world? Maybe the reaction to seeing someone smile makes you happy and unconsciously smile back? This made me think – well can the opposite happen? What if we see someone and have a face that’s indifferent with emotions as we make eye contact – could that make them feel indifferent or angry? Did our indifferent expressions just let out a negative energy into the world?
It turns out that our emotional expressions do have a significant role on our well-being – more than you’d think. The act of smiling can reduce risk of cardiovascular disease by lowering physiological arousal, increasing heart rate variability, and lowering concentrations of inflammatory markers (Tucker et al., 2017). Although Tucker et al. (2017) showed us that the skill of expressing a positive emotion (i.e. happiness) was associated with lower cardiovascular risk (CVD) scores –their sample was relatively low in CVD risk factors to begin with. This leaves us to wonder if positive emotional expressions can have the same power (impact) for people with poorer health and at a greater risk with CVD. While research tries to dissect our everyday life and experiences, the isolation of an individual in a lab and expressing emotions at a computer monitor is completely different from a human being. For example, if I smile at a stranger (expressing joy/happiness) and they respond to me negatively, then I might not be in a joyful mood anymore. I might feel angry now because of their reaction.
While expressing happiness may have positive associations with lowering heart risks, anger and hostility actually increase the risk – specifically in ischemic heart disease (Newman et al., 2011). Patients who were observed as expressing hostility, by interviewers, were associated with an increased risk of IHD (Newman et al., 2011). This research suggests that hospitals should use interviewer based methods when coding for hostile behavior in patients, rather than asking a patient to self-report their emotions. However, in the attempt to prove that observing hostility was the superior method, Whooley and Wong (2011) refuted that if 90% of their patients observed hostility, how can they make an equal comparison and analysis to self-reporting systems when determining IHD risks. More importantly Whooley and Wong (2011) emphasize that Newman et al. (2011) were too focused on the differences of methods in understanding hostility that they did not explore what potential mechanisms could link hostility with heart disease.
As we can see, researchers are constantly trying to understand how our emotional expressions and experiences can affect our risk to heart disease, but it can be difficult to determine at times what’s the most appropriate method and how much external validity the experiment will have. In Why Zebras Don’t Get Ulcers, by Sapolsky (2004), the author explores the basic functions of our cardiovascular system and parasympathetic nervous system in relation to heart disease. Tying in similar topics as Tuck et al. (2017) and Newman et al. (2011), Sapolsky highlights that experiencing extreme joy or extreme stress can have similarly large demands on your heart which could make you more vulnerable to heart disease (Sapolsky, 2004). Constantly having chronic stress or extreme moments of joy can affect your parasympathetic nervous system to the point that it’s harder for your heartbeat to slow down (minimal variability) – which can gradually damage your system and make it more sensitive to acute stressors (Sapolsky, 2004). As acute stressors can potentially cause more harm on a damaged system, wear-and-tear become a greater concern. If acute stressors are causing greater harm than before then it forces your body to constantly work harder. In that process the amount and force of blood constantly returning to your heart may lead to a left ventricular hypertrophy – which is the single best predictor of cardiac risk (Sapolsky, 2004).
Returning to my original point, as social beings we are constantly experiencing and expressing a variety of emotions either initiated by us or as a reaction to another person or event. It is important to understand that these emotional experiences and expressions very much have a significant role in the well-being of our heart and bodily functions.