While most physical attributes we have can be linked to certain genes, our personalities are much more complicated. In fact, most personality traits we possess are thought to be some combination of genetic predisposition (the genes your parents passed down to you) and environmental factors (i.e.—how you were raised, how much air pollution you were exposed to, etc.). Researchers at the University of Arizona, led by Dr. Kory Floyd, were interested in what drives certain people to be more physically affectionate than others. Could there be some genetic component to the expression of physical affection?

In their study, Floyd’s lab looked at 464 pairs of adult twins between the ages 19 and 84. Approximately half of the twins were identical and half were fraternal, meaning either 100% of their genetic information was shared (in the case of identical twins) or roughly 50% (in the case of fraternal twins). The participants were given a set of statements to evaluate and assess how much physical affection they would typically express. If genes weren’t involved, we would expect all twins who were raised in the same household (same set of environmental factors) to express similar amounts of physical affection; but this was not the case! Identical twins, especially female twins, scored much more similarly, suggesting there may be a larger genetic component than originally hypothesized. Floyd’s lab also found that “unique environmental factors,” such as friends or individual experiences, mattered more than the shared environment of the home in shaping a person’s propensity for physical affection. At the end of the day, this study doesn’t completely explain why certain people show more physical affection than others; but it does certainly shed some light on the intricacies of personality development.

Lastly, Floyd offers some advice to people struggling with so-called “skin hunger” in the time of COVID. This term refers to people who are longing for more physical touch during the practice of social distancing. He recommends petting household animals, engaging in self-massage, and using a pillow or blanket that feels good against the skin. He understands that these suggestions may be not be the perfect substitute for physical touch but they are better than nothing while we are all trying to be safe.