Dec 12, 2012
At this point, we can only speculate, as the study was not designed to answer this question. One possibility is that there is something about being more extroverted and developing closer social bonds that protects them against stressors. Another possibility, and one that receives support from studies of rhesus macaques and humans, is that extroversion is an indicator of immune system functioning. It may also be that common genes are associated with extroversion and longevity. Naturally, some, all, or none of these possibilities may be involved.
Alexander Weiss is a senior lecturer in psychology at The University of Edinburgh.