Researchers Find That These Two Personality Traits May Be Tied To Alzheimer’s Pathology


Scientists and researchers have noticed a buildup of what they call the amyloid plaques and tau tangles in the brain. This has been associated with the development of Alzheimer’s disease and other related dementias. Hence, they looked into it further and conducted a new study. They had discovered that being neurotic or conscientious may increase or decrease, respectively, the chances of developing the buildups.

However, they have yet to answer on whether or not this association is a result of lifestyle practices that may characterize these traits. Previous research has also found that there are personality traits that are at risk for Alzheimer’s disease and related dementias. At this point in time, these experts have yet to fully establish the causal link.

Studying the Links

As mentioned, the development of amyloid plaques and insoluble tangles of tau proteins found in the brain may be linked with Alzheimer’s and other related dementias. Hence, the latest study looks further into a possible connection between personality traits and the abovementioned health issues. 

The research discovers how neuroticism increases the chances of the person to develop amyloid plaques and tau tangles. Basically, being conscientious has the opposite effect. The latter trait lowers the chances of the person to develop them.

Antonio Terracciano, Ph.D., is a professor in the Department of Geriatrics at Florida State University. He talked about this new study in detail and said,  “We have done studies showing who’s at risk of developing dementia, but those other studies were looking at the clinical diagnosis. Here, we are looking at the neuropathology; that is, the lesions in the brain that tell us about the underlying pathological change.”

The paper of the study has finally been published in the journal Biological Psychiatry.

Neuroticism vs. Conscientiousness

Neuroticism and conscientiousness – these are two of the so-called Big Five personality traits often pointed out by researchers and those working in the mental health field. These traits become apparent early on in life and. The study points out that these “have a broad impact on important life outcomes.” These are the Big Five:

  1. Conscientiousness: This talks about a person who is responsible, careful, and goal- or detail-oriented.
  2. Neuroticism: A person prone to feeling unsettling emotions like anxiety and depression.
  3. Openness: This is someone who is open to feeling new experiences. He or she is curious and wants to know more about the world they live in.
  4. Extraversion or Extroversion: This is a person who looks for excitement. He or she is thought to be on the more active and more highly sociable side of life.
  5. Agreeableness: This describes someone respectful, compassionate, trusting. He or she stays away from issues and problems.


Two Analyses Made with One Pair of Conclusions

The authors of the study performed two kinds of investigations. They recruited around 3,000 participants for this. The first step made was to analyze the data they gathered from people who participated in the Baltimore Longitudinal Study of Aging (BLSA). For those unfamiliar with it, this was an ongoing study of community-dwelling adults. The participants were then asked to fill out a 240-item questionnaire that was based on the Revised NEO Personality Inventory test. This was done in order to identify their Big Five personality traits.

Within a year upon the completion of the questionnaire, the absence or presence of amyloid plaques and tau proteins in their brains was studied by asking the participants to get PET scans. The second part of the study was a meta-analysis of 12 studies. This looked into associations between the pathology of Alzheimer’s disease and personality traits.


The Analyses Discovery

Both the BLSA-based study and meta-analysis arrived to one and the same kind of conclusion: People with high neuroticism or low conscientiousness scores had more likelihood to develop amyloid plaques and tau tangles. On the other hand, those with high conscientiousness or low neuroticism scores were less likely to develop the disease.

Dr. Claire Sexton is the director of scientific programs and outreach at Alzheimer’s Association. She was not part of the group who conducted the study but she shared her expert advice with Medical News Today. She said, “It’s especially intriguing to see complementary findings between the BLSA cohort and the meta-analyses.“

She further stated, “Research has looked at other personality traits, such as openness and extraversion, in relationship with dementia, but neuroticism and conscientiousness has the strongest link, according to recent meta analyses.”

When asked if the link occurs at some specific level of neuroticism or conscientiousness, Prof. Terracciano explained, “These associations seem to be linear without a threshold […] and there is no specific level that triggers resistance or susceptibility.”

The researchers also found that the link between these personality traits and pathology was at its most potent in those who were cognitively normal at the time when the assessment in the BLSA study or studies included in the meta-analysis had taken place. Hence, this somewhat shows how personality type may be a risk factor before the amyloid and tau emerge. The opposite, however, seems to be untrue. The researchers noted, “These patterns suggest that the associations are not emerging phenomena owing to personality change with disease progression, as would be expected with reverse causality.”


Is There a Causal Link?

“Because this study is observational, we can’t say for sure what the mechanisms are, and much more research is needed,” Dr. Sexton explained.

However, she gave a list of specific possibilities for it. She said, “One potential pathway is inflammation, which is associated with personality and the development of Alzheimer’s biomarkers. Lifestyle is another potential pathway. For example, highly conscientious individuals have been shown to have healthier lifestyles — in terms of physical activity, smoking, sleep, depression, cognitive stimulation, etc. — than those with lower conscientiousness. There is a solid body of research connecting lifestyle, dementia risk, and biomarkers.”

Prof. Terracciano also suggested another idea when he spoke to MNT. He told them, “There are aspects of neuroticism and conscientiousness that might directly impact the risk of dementia. Traits like neuroticism shape our emotional life, the way we cope with stress and deal with our feelings. Conscientiousness is defined by our level of grit, persistence, and planful attitudes.”