For years, researchers and clinicians have been looking for early signs of cognitive decline in adults, particularly in older populations. Alzheimer’s disease, the most common form of dementia, has become a major focus in this search, and scientists have been investigating various ways to identify its early symptoms. One area of interest has been the connection between major personality changes, such as an increase in neuroticism, and memory impairment. Some clinicians believe that personality shifts could serve as early indicators of dementia, but one sociologist warns against rushing to conclusions based on this idea alone.
In a recent study published in Scientific Reports, Katsuya Oi, an associate professor of sociology at Northern Arizona University, challenges the notion that personality changes—especially an increase in neuroticism—are reliable signs of impending memory impairment. Oi’s research sheds light on the complexity of personality shifts in older adults and argues that they do not always point to cognitive decline. His findings are based on data collected from more than 12,000 Americans aged 50 and older as part of the Health and Retirement Study, which tracked changes over a period from 2006 to 2020.
The Search for Early Cognitive Decline Indicators
As people age, changes in memory and cognition are often seen as natural consequences of growing older. But when these changes seem more significant, they can signal the early stages of Alzheimer’s disease or other forms of dementia. Early detection is critical because it offers the potential to intervene, slow progression, and improve quality of life for individuals. With that goal in mind, researchers have explored a variety of factors that might serve as early warning signs of cognitive decline.
One commonly discussed sign is neuroticism—the tendency to experience negative emotions like anxiety, depression, or irritability. Studies have suggested that people who are more neurotic may be at higher risk of developing Alzheimer’s. This has led some clinicians to propose that shifts in personality—particularly an increase in neurotic traits—could serve as an early indication of memory impairment. As a result, there has been a growing emphasis on linking personality changes with cognitive decline in clinical settings, especially given the ease and low cost of assessing personality traits compared to other diagnostic methods.
The Role of Personality in Cognitive Health
Oi’s study challenges this emerging assumption. While he acknowledges that personality changes do occur as people age, he emphasizes that these shifts should not automatically be associated with the onset of dementia. In fact, his research found that personality changes in older adults were more strongly associated with life stressors than with memory impairment. He argues that clinicians may be jumping to conclusions by attributing personality shifts solely to cognitive decline without considering the broader context.
The study analyzed the “Big Five” personality traits—neuroticism, openness, extraversion, agreeableness, and conscientiousness—in a sample of older Americans. The researchers found that, on average, all five personality traits showed small but significant decreases over time, regardless of whether the individuals had memory impairments. This finding aligns with previous research, which suggests that, as people grow older, their personalities generally become less pronounced, and they may become more socially and emotionally withdrawn.
However, Oi and his colleague Cleothia Frazier of Pennsylvania State University noted that some individuals exhibited more noticeable personality changes. For instance, some participants demonstrated increased neuroticism, often marked by greater emotional instability or anxiety, while others showed a decline in conscientiousness, which is associated with the ability to plan, organize, and act toward long-term goals.
Stress: A Major Contributor to Personality Changes
What stood out in Oi’s findings was the connection between personality changes and stress. The study revealed that life stressors—such as health problems, financial difficulties, the death of a loved one, or other personal losses—were responsible for a substantial portion of the changes observed in neuroticism. In fact, stress-related events accounted for 25-35% of the changes in neuroticism observed over an eight-year period. This suggests that, for many individuals, stress plays a major role in altering personality traits.
Oi believes that this finding is crucial because it highlights that personality changes can be driven by many different factors, not just the onset of Alzheimer’s or other dementias. While some of these stress-related changes could overlap with early signs of cognitive decline, they could just as easily be the result of a challenging life event or ongoing personal struggles. For instance, job stress, health problems, financial strain, or family issues could all contribute to an increase in neuroticism or a decrease in conscientiousness.
Implications for Clinical Practice
The widespread belief that personality changes, particularly an increase in neuroticism, could signal early-stage dementia is a relatively recent development in the field of aging and cognitive health. According to Oi, this idea has gained traction largely because it offers a simple and low-cost way to screen for memory impairment on a large scale. Personality tests can be administered quickly, making them an attractive option for clinicians looking to identify potential cases of dementia in older populations.
However, Oi’s study cautions against using personality changes as a sole diagnostic tool for cognitive decline. While it is true that some individuals who exhibit increased neuroticism may indeed be at risk for developing dementia, Oi stresses that personality changes should not be assumed to be a direct indicator of cognitive impairment. There are many life factors that can influence personality, and clinicians need to take these into account when assessing patients.
In fact, Oi argues that focusing too much on personality changes as early warning signs could lead to misdiagnoses or unnecessary alarm. For example, an individual who is experiencing significant stress—perhaps due to caregiving responsibilities, financial struggles, or health problems—may show signs of increased neuroticism, but this does not necessarily mean they are on the verge of developing Alzheimer’s disease. In these cases, the focus should be on addressing the underlying stressors, rather than immediately jumping to the conclusion that cognitive decline is imminent.
Stress and Inequality: The Bigger Picture
Oi’s findings also bring attention to the broader societal factors that contribute to stress and its impact on cognitive health. He argues that the high levels of stress experienced by people facing poverty, discrimination, health disparities, or lack of access to care have significant consequences for both mental health and personality development. These systemic issues are not just personal hardships but are linked to broader social inequalities that can affect people’s physical and emotional well-being.
The stress of struggling to make ends meet, caring for family members with health issues, or dealing with financial insecurity can lead to changes in personality and may even contribute to cognitive decline over time. Inequality, in particular, plays a central role in exacerbating stress levels, and addressing this issue could help reduce the risk of cognitive decline. Oi suggests that tackling systemic inequalities should be a priority if we want to create a society that supports cognitive health for all individuals.
“Imagine working into your 70s or 80s to make ends meet or losing sleep over hospital bills,” Oi said. “These are inhumane stressors that not only affect day-to-day life but also increase risks of cognitive decline. To reduce stress, we need to address systemic inequalities.”
A Holistic Approach to Cognitive Health
For Oi, the key takeaway from his study is the importance of adopting a holistic approach to cognitive health. Instead of focusing exclusively on personality changes as potential indicators of dementia, Oi advocates for a more nuanced approach that takes into account the full range of factors that can influence mental well-being. By understanding that stress, life events, and systemic inequalities can shape both personality and cognition, healthcare providers can better support older adults in managing their mental and emotional health.
Oi recommends that clinicians work closely with patients and their caregivers to understand the context behind any observed personality changes. If changes are indeed linked to stress, addressing the source of the stress—whether it’s a health issue, financial difficulty, or family conflict—should be the first priority. By reducing stress and supporting individuals in coping with life challenges, clinicians can help mitigate the risk of further cognitive decline and improve overall quality of life.
Conclusion
In conclusion, Katsuya Oi’s research challenges the emerging view that major personality changes—particularly increases in neuroticism—are reliable early indicators of dementia. While these changes are certainly common as people age, they are often driven by life stressors such as loss, health struggles, or financial hardship, rather than cognitive impairment. Oi’s findings underscore the need for a more comprehensive approach to understanding personality changes in older adults, one that takes into account the role of stress, life circumstances, and systemic inequalities. By doing so, we can better address the underlying causes of personality shifts and support older individuals in maintaining their cognitive health and overall well-being.
Reference: Katsuya Oi et al, Testing of significant changes in big-five personality factors over time in the presence and absence of memory impairment and life-related stress, Scientific Reports (2024). DOI: 10.1038/s41598-024-70388-5