Having specific personality traits might be connected to our risk of developing cognitive problems later on in life, new research suggests – and that in turn might point to better ways of treating issues like dementia.

A total of 1,954 volunteers without a formal diagnosis of dementia took part in the study, filling out personality questionnaires that were cross-checked against their health records and any cognitive problems as they got older. Curiously enough, organized and self-disciplined people appeared less likely to develop mild cognitive impairment, whereas neurotic people were more prone to it.

As this was a correlational study, it's not clear if there are fundamental aspects of biology underpinning the link, but the researchers have their suspicions.

"Personality traits reflect relatively enduring patterns of thinking and behaving, which may cumulatively affect engagement in healthy and unhealthy behaviors and thought patterns across the lifespan," says psychologist Tomiko Yoneda, from the University of Victoria in Canada.

"The accumulation of lifelong experiences may then contribute to susceptibility of particular diseases or disorders, such as mild cognitive impairment, or contribute to individual differences in the ability to withstand age-related neurological changes."

Personality traits are usually divided into the so-called 'Big Five', which are agreeableness, openness to experience, conscientiousness, neuroticism, and extraversion. This particular study examined the last three.

Conscientiousness covers traits including being responsible, being well organized, working hard, and being goal-oriented. Those who scored highly for conscientiousness on a scale of 0–48 were less likely to develop impairments – a 6 point increase on the scale was associated with a 22% lower risk.

Those who don't score highly for neuroticism tend to be more emotionally stable, and less likely to experience depression, anxiety, and self-doubt. A low neuroticism score matched a lower risk of cognitive impairment in later life, with 7 more points on the neuroticism scale (0–48) equating to a 12% increased risk.

No link between extraversion and impairment risk was found – although extraverts tended to maintain normal cognitive functioning for longer in their lives when high conscientiousness or low neuroticism was also present. Extraversion involves traits such as assertiveness, enthusiasm for social interaction, and directing energy towards people.

"Analyses revealed that all three personality traits are associated with non-impaired cognitive health span to some degree, particularly for female participants, but that personality traits are not associated with total longevity," write the researchers in their published paper.

The team didn't find any link between personality traits and life expectancy, nor does the study suggest that these characteristics are the cause of cognitive impairment – only that there appears to be some kind of relationship, one that's worth investigating in future studies.

Similar findings have been reported by researchers before, but there's still a lot of uncertainty about how these personality traits matter in terms of the timing of cognitive problems, and how many years certain characteristics might delay them for.

While this study used almost 2,000 people as its sample size, it was dominated by White (87%) and female (74% participants). Studies carried out in the future could improve on these findings by looking at groups of participants that are both larger as well as more diverse.

"These findings provide novel understanding of the simultaneous associations between personality traits and transitions between cognitive status categories and death, as well as cognitive health span and total longevity," write the researchers.

The research has been published in the Journal of Personality and Social Psychology.