Humans are very similar in a lot of ways — we all have two eyes and ears, walk on two legs, and have a brain that weighs around 3 Ibs. But our personalities make us distinctly different. Psychologists and neuroscientists don’t agree exactly on what determines our personality. Some think of personality from a trait perspective with different spectrums (i.e., introversion, extraversion) that define personalities. Others think of personality from a social cognitive perspective believing that our personality forms by observing others and learning what to incorporate into own personality.

Regardless of what exactly determines our personality, it is interesting to wonder if our personalities can effect our health.

This week, I want to share with you the results of a recent study which looked at how our personalities in adolescence could affect our risk for dementia five decades later. Dementia is a cognitive disorder that itself causes personality changes so it can be difficult to disentangle whether one’s personality is increasing one’s risk for dementia or if dementia is causing changes in personality.

This particular study gets around this problem by utilizing the Project Talent survey that was given to a random sample of 5% of all the high schools in the US in 1960. It’s extremely unlikely that any kind of dementia-related cognitive decline is occurring in adolescence, so the researchers claim they can be more confident that the causal chain isn’t going in the wrong direction.

Calm, Vigor, and Maturity was associated with lower risk of dementia 5 decades later

Some ~350,000 students completed a personality questionnaire and the researchers were able to enroll and track the health outcomes of ~82,000 people 54 years later using a Medicare database. Interestingly, they found that students who had high scores in Vigor, Calm, and Maturity were less likely to develop dementia over their lifetime. Vigor, in this sense, is a kind of sense of vitality, high levels of energy, and an active lifestyle. The study found that high scores of Vigor lowered dementia risk by 7%.

Students in the study who had low scores of neuroticism (or high scores of “calm”) overall had a healthier response to stress. Chronic stress is a causal factor in many diseases, so it’s not surprising to see a calm personality lower dementia risk.

How could personality lead to dementia?

Although this study is interesting to me, an obvious question for me is how