Self-reported and mother-rated personality traits at age 16 are associated with cognitive function measured concurrently and 30 years later

Cognitive ability, gender, and well-being in school contexts: longitudinal evidence from Sweden

While well-being does generally constitute a moderate predictor of school achievement, research on the predictive validity of cognitive ability for well-being in school contexts remains scant. The current study analyzed longitudinal relations between cognitive ability measured at age 13 (Grade 6) and well-being measured at age 18 (Grade 12, valid N = 2,705) in a Swedish sample, using several multivariate model techniques. The results indicate that cognitive ability was not a statistically significant predictor when several predictors were entered in a multiple regression model. However, gender was a significant covariate as girls and young women have a substantially lower degree of self-reported well-being. This casts light on the limitations of cognitive ability as a construct for some non-cognitive outcomes, at least in shorter and narrower spatial-temporal contexts.

Personality traits and mediating pathways to mortality risk: A systematic review

OBJECTIVE

Personality traits have been regularly linked with all-cause mortality risk. However, what mechanisms may provide an indirect pathway from personality traits to mortality is unclear. We sought to systematically review the literature and provide an overview of the potential mechanisms that have been identified in the literature.

METHOD

Five electronic databases (PubMed, Web of Science, CINAHL, PsycInfo, and PsycArticles) were searched from inception to January 27, 2023. From 611 studies initially identified, seven studies met the final inclusion criteria. These seven papers have a combined sample of 60,104 individuals (M = 8,585, SD = 14,600; range 957-44,094).

RESULTS

These papers found that several variables, such as smoking, inflammation biomarkers, blood pressure, and sleep, mediated the relationship between various personality traits and mortality. There was considerable variation in the impact of results across cohorts, even when looking at similar variables, and notable differences in methodological approaches and reporting were discussed.

CONCLUSIONS

This review identified a small pool of research looking at a range of indirect pathways (mediating variables). The review identified traits with well-established associations with mortality risk, such as neuroticism, do not have consistent findings in the mediation literature and a high level of variance in the degree to which mediators account for the personality-mortality relation between different cohorts. Despite these limitations, it is clear that examining indirect effects (mediation) has a crucial role to play in developing our understanding of the complex pathways that connect personality-mortality risk. We identify several avenues and considerations for future research. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Neuroticism and white matter hyperintensities

Neuroticism is a major risk factor for neurodegenerative disorders, such as Alzheimer's disease and related dementias. This study investigates whether neuroticism is associated with white matter hyperintensities and whether this measure of brain integrity is a mediator between neuroticism and cognitive function. Middle-aged and older adults from the UK Biobank (N = 40,602; aged 45-82 years, M = 63.97, SD = 7.66) provided information on demographic and health covariates, completed measures of neuroticism and cognition, and underwent magnetic resonance imaging from which the volume of white matter hyperintensities was derived. Regression analyses that included age and sex as covariates found that participants who scored higher on neuroticism had more white matter hyperintensities (β = 0.024, 95% CI 0.015 to 0.032; p < .001), an association that was consistent across peri-ventricular and deep brain regions. The association was reduced by about 40% when accounting for vascular risk factors (smoking, obesity, diabetes, high blood pressure, heart attack, angina, and stroke). The association was not moderated by age, sex, college education, deprivation index, or APOE e4 genotype, and remained unchanged in sensitivity analyses that excluded individuals with dementia or those younger than 65. The mediation analysis revealed that white matter hyperintensities partly mediated the association between neuroticism and cognitive function. These findings identify white matter integrity as a potential neurobiological pathway that accounts for a small proportion of the association between neuroticism and cognitive health.

The Big Five as Predictors of Cognitive Function in Individuals with Bipolar Disorder

The connection between cognitive function and the "Big Five" personality traits (openness, conscientiousness, extraversion, agreeableness, and neuroticism) in the general population is well known; however, studies researching bipolar disorder (BD) are scarce. Therefore, this study aimed to investigate the Big Five as predictors of executive function, verbal memory, attention, and processing speed in euthymic individuals with BD (cross-sectional: n = 129, including time point t1; longitudinal: n = 35, including t1 and t2). Participants completed the NEO Five-Factor Inventory, the Color and Word Interference Test, the Trail Making Test, the d2 Test of Attention Revised, and the California Verbal Learning Test. The results showed a significant negative correlation between executive function and neuroticism at t1. Changes in cognitive function between t1 and t2 did not correlate with and could not be predicted by the Big Five at t1. Additionally, worse executive function at t2 was predicted by higher neuroticism and lower conscientiousness at t1, and high neuroticism was a predictor of worse verbal memory at t2. The Big Five might not strongly impact cognitive function over short periods; however, they are significant predictors of cognitive function. Future studies should include a higher number of participants and more time in between points of measurement.

IQ in Adolescence and Cognition over 50 years later: The Mediating Role of Adult Personality

There is substantial evidence for the association between higher early life IQ and better cognition in late life. To advance knowledge on potential pathways, the present study tested whether Five-Factor Model personality traits in adulthood mediate the association between adolescent IQ and later-life cognition. Participants were from the Graduate sample of the Wisconsin Longitudinal Study on Aging (WLS; N= 3,585). IQ was assessed in 1957 (about age 17), personality was assessed in 2003-2005 (age = 64), and cognition was assessed in 2011 (age = 71). Controlling for demographic factors, higher IQ in adolescence was related to higher openness, lower neuroticism, lower extraversion, lower agreeableness and lower conscientiousness in adulthood. Higher openness partially mediated the association between higher IQ and better cognition. Additional analyses indicated that the pattern of associations between IQ, personality and cognition was similar when the polygenic score for cognition was included as an additional covariate. Although effect size were small, this study provides new evidence that openness in adulthood is on the pathway between early life IQ and later-life cognition.

Facets of Personality and Risk of Cognitive Impairment: Longitudinal Findings in a Rural Community from Sardinia

Background: Few studies have examined the associations between personality facets and dementia risk and rarely included individuals from rural settings or with low education. Objective: To examine the association between personality and the risk of cognitive impairment. Methods: Participants (N = 1,668; age 50 to 94 at baseline; 56.4% women; 86.5% less than high school diploma) were from a rural region of Sardinia (Italy) who completed the Revised NEO Personality Inventory (NEO-PI-R) during the first wave (2001–2004) and the Mini-Mental State Examination (MMSE) at waves two to five (2005–2021). Cox regression was used to test personality and covariates as predictors of cognitive impairment based on MMSE education-adjusted cutoffs. Results: During the up to 18-year follow-up (M = 10.38; SD = 4.76), 187 individuals (11.2%) scored as cognitively impaired. Participants with higher neuroticism (particularly the depression facet [HR = 1.22, 95% CI = 1.06–1.40]), and lower agreeableness (particularly the modesty facet [HR = 0.83, 95% CI = 0.71–0.97]) and lower conscientiousness (particularly the dutifulness facet [HR = 0.78, 95% CI = 0.67–0.92]) were at higher risk of cognitive impairment. Lower warmth ([HR = 0.75, 95% CI = 0.65–0.87], facet of extraversion) and ideas ([HR = 0.76, 95% CI = 0.65–0.89], facet of openness) were also associated with increased risk of impairment. These associations were virtually unchanged in models that accounted for other risk factors, including smoking, depression, obesity, hypertension, diabetes, and apolipoprotein E (APOE) ɛ4 carrier status. Across the five domains, sex and the APOE variant did not moderate the associations. Conclusion: In a sample with demographic characteristics underrepresented in dementia research, this study identifies personality domains and facets most relevant to the risk of cognitive impairment.

Socioeconomic status, internalizing and externalizing behaviors, and executive function in adolescence: A longitudinal study with multiple informants

This study examines whether behavior problems reported by the self and others are associated prospectively with executive function in adolescence and whether these behaviors mediate the association between family and neighborhood socioeconomic status and executive function. Participants (N = 4,164) from the Longitudinal Study of Australian Children (LSAC) reported their behaviors at ages 10-11; mothers, fathers, and teachers also rated participants' behaviors. Four years later, participants completed an executive function battery that measured attention, working memory, and error monitoring. As rated by the self, mother, father, and teacher, hyperactivity and emotional symptoms had the most consistent associations with worse performance on the executive function tasks. The associations were generally similar across the four reporters. Hyperactivity mediated the association between family SES in childhood and adolescent executive function. None of the behaviors mediated the association between neighborhood SES and executive function. The present research suggests that behavior problems prospectively predict executive function in adolescence and may be one mechanism of the relation between family SES and executive function.

Personality traits at age 16 and risk of metabolic syndrome at age 46

OBJECTIVE

To examine whether five-factor model personality traits at age 16 are associated with risk of metabolic syndrome 30 years later at age 46 and whether adolescent personality mediates the association between childhood social class and midlife metabolic health.

METHODS

Participants were from the British Cohort Study 1970, a birth cohort study of participants all born in the same week in 1970. Personality was assessed by participants' mothers (n = 3819) and participants' themselves (n = 2697) at age 16. The five components of the metabolic syndrome were measured at the age 46 assessment: elevated blood pressure, glucose, triglycerides, waist circumference and lower HDL cholesterol.

RESULTS

Mother-rated neuroticism and mother-rated conscientiousness at age 16 were associated with risk of metabolic syndrome at age 46 (OR = 1.19, 95% CI = 1.04, 1.36 and OR = 0.70, 95% CI = 0.62, 0.78, respectively). Self-reported neuroticism was also associated with metabolic syndrome risk (OR = 1.43, 95% CI = 1.08, 1.91). Mother-rated conscientiousness at age 16 accounted for 10% of the association between childhood social class and metabolic health at age 46. None of the other traits were significant mediators.

CONCLUSION

Consistent with lifespan models of personality and health, age 16 personality traits were associated with metabolic health measured 30 years later. Personality traits may also function as a mechanism through which early-life socioeconomic status contributes to midlife health.

Personality Associations With Amyloid and Tau: Results From the Baltimore Longitudinal Study of Aging and Meta-analysis

BACKGROUND

Higher neuroticism and lower conscientiousness are risk factors for Alzheimer's disease and related dementias, but the underlying neuropathological correlates remain unclear. Our aim was to examine whether personality traits are associated with amyloid and tau neuropathology in a new sample and meta-analyses.

METHODS

Participants from the BLSA (Baltimore Longitudinal Study of Aging) completed the Revised NEO Personality Inventory and underwent amyloid (11C-labeled Pittsburgh compound B) and tau (18F-flortaucipir) positron emission tomography.

RESULTS

Among cognitively normal BLSA participants, neuroticism was associated with higher cortical amyloid burden (odds ratio 1.68, 95% CI 1.20-2.34), and conscientiousness was associated with lower cortical amyloid burden (odds ratio 0.61, 95% CI 0.44-0.86). These associations remained significant after accounting for age, sex, education, depressive symptoms, hippocampal volume, and APOE ε4. Similar associations were found with tau in the entorhinal cortex. Random-effects meta-analyses of 12 studies found that higher neuroticism (N = 3015, r = 0.07, p = .008) and lower conscientiousness (N = 2990, r = -0.11, p < .001) were associated with more amyloid deposition. Meta-analyses of 8 studies found that higher neuroticism (N = 2231, r = 0.15, p < .001) and lower conscientiousness (N = 2206, r = -0.14, p < .001) were associated with more tau pathology. The associations were moderated by cognitive status, with stronger effects in cognitively normal compared with heterogeneous samples, suggesting that the associations between personality and proteopathies are not phenomena that emerge with neuropsychiatric clinical symptoms.

CONCLUSIONS

By aggregating results across samples, this study advances knowledge on the association between personality and neuropathology. Neuroticism and conscientiousness may contribute to resistance against amyloid and tau neuropathology.

Pathways from early life SES to dementia risk in old age: The role of personality

OBJECTIVE

This study investigates the association between childhood socioeconomic status (cSES) and risk of cognitive impairment in older adulthood, and whether Five Factor Model personality traits mediated this association.

METHODS

A sample of 9,995 participants (mean age = 67.01 years) from the Health and Retirement Study were followed every two years from 2006 to 2018. cSES was tested as a predictor of risk of dementia and risk of cognitive impairment not dementia (CIND). Personality was tested as a mediator of these associations. Models were adjusted for age, gender, ethnicity, race, education, and baseline year.

RESULTS

Although effect sizes were modest, results indicated that lower cSES was associated with higher risk of dementia (HR=0.88, [0.775, 0.985]). Higher cSES was also associated with higher Conscientiousness and lower Neuroticism. Conscientiousness and Neuroticism each accounted for 7.9% of the total effect of cSES on dementia. Results were similar for CIND.

CONCLUSIONS

Early childhood socioeconomic factors may contribute to cognitive impairment in older adulthood, an association mediated, in part, through adult personality traits.