The Hearts of Introverts and Extraverts

If you want to understand the differences between introverts and extraverts, one place you could look is their brains. Another, apparently, is their hearts.

Recently, a study from researchers at Shaanxi Normal University in China and National University of Ireland found several differences in introverts’ and extraverts’ cardiovascular responses to stressful social situations.

In the study, 166 college students were asked to participate in either moderately or highly stressful social situations. Both situations involved public speaking, but in the highly stressful situation the speakers were subject to more evaluation and scrutiny.

Meanwhile, researchers monitored the speakers’ heart rates and blood pressure.

It turned out that extraverts and introverts reacted differently in the two kinds of public speaking situations. In the moderately stressful situation, extraverts’ heart rates changed less on average than introverts’. In the highly stressful version of the public speaking task, though, extraverts’ heart rates changed more, as did their blood pressure.

Even more interestingly, when the introverts and extraverts were repeatedly exposed to the stressful social situations, they adapted in different ways.

Or, to be more exact, the extraverts adapted while the introverts didn’t – at least in terms of heart rate and blood pressure. In both the moderate and highly stressful speaking situations, extraverts’ blood pressure rose less when they subsequently repeated the task. Moreover, their blood pressure and heart rates returned to normal more quickly following the task after repeated exposure.

In other words, one difference between introverts and extraverts may be that when extraverts are repeatedly exposed to a stressful social situation, they adapt more quickly – judging by their heart rates and blood pressure, anyway.

In the words of the researchers, then, a possible interpretation of these findings is that “individuals higher on extraversion exhibit physiological flexibility to cope with social challenges and benefit from adaptive cardiovascular responses.”

Image: Flickr/Marty D