Greta has a jar of candy in her office, and she eats exactly one piece of candy per day (as well as offering it to her students whenever they visit). By contrast, if I have candy within 50 yards of my office, it will disappear within a day or two at the most (which is why I don’t keep candy in my office!). Why can Greta resist temptation while I cannot? A new study suggests that part of the reason may have to do with heart rate.
The Science Daily headline, “Why We Give In To Temptation,” is a little misleading. The research doesn’t show why I give into temptation while Greta does not; it simply demonstrates some key physiological differences between people who do and don’t have strong will power:
A measure of cardiac regulation called “heart rate variability” (HRV) appears to be linked to self regulation.
The researchers conducted a two-part study in order to test their hypothesis. In the first, participants were instructed to fast for three hours in order to take part in what they believed was a “physiology of food preference” experiment. Participants’ HRV was monitored while they were presented with a tray of cookies, candy and….carrots. Temptation, in this case, was indicated by giving into the tastier but decidedly less healthy snack of cookies and candy.
HRV as it turns out was considerably higher when people were working to resist temptation (eating carrots rather than cookies and chocolate) than when they were not, suggesting that HRV was mirroring the self regulation taking place.
Participants with higher HRV were also more likely to persist at a difficult (actually impossible) puzzle. But does high HRV cause people to have better self regulation? The study doesn’t show that. Perhaps high HRV and self-regulation are both caused by some other factor — the real root of self control. But it’s also possible that we can all get more will power just by taking a pill to increase our HRV.