To examine (1) the association between purpose in life and multiple domains of cognitive function and informant-rated cognitive decline, affect, and activities; (2) whether these associations are moderated by sociodemographic factors, cognitive impairment, or depression; (3) whether the associations are independent of other aspects of well-being and depressive symptoms.

As part of the 2016 Harmonized Cognitive Assessment Protocol from the Health and Retirement Study, participants completed a battery of cognitive tests and nominated a knowledgeable informant to rate their cognitive decline, affect, and activities. Participants with information available on their purpose in life from the 2014/2016 Leave Behind Questionnaire were included in the analytic sample (N = 2,812).

Purpose in life was associated with better performance in every cognitive domain examined (episodic memory, speed-attention, visuospatial skills, language, numeric reasoning; median β =.10, p <.001; median d =.53). Purpose was likewise associated with informant-rated cognitive decline and informant-rated affective and activity profiles beneficial for cognitive health (median β =.18, p < .001; median d =.55). There was little evidence of moderation by sociodemographic or other factors (e.g., depression). Life satisfaction, optimism, positive affect, and mastery were generally associated with cognition. When tested simultaneously with each other and depressive symptoms, most dimensions were reduced to non-significance; purpose remained a significant predictor.

Purpose in life is associated with better performance across numerous domains of cognition and with emotional and behavioral patterns beneficial for cognitive health that are observable by knowledgeable others. These associations largely generalize across demographic and clinical groups and are independent of other aspects of well-being.

This study examined the association between loneliness and risk of incident all-cause dementia and whether the association extends to specific causes of dementia.

Longitudinal.

Community.

Participants were from the UK Biobank (N = 492,322).

None.

Loneliness was measured with a standard item. The diagnosis of dementia was derived from health and death records, which included all-cause dementia and the specific diagnoses of Alzheimer’s disease (AD), vascular dementia (VD), and frontotemporal dementia (FTD), over 15 years of follow-up.

Feeling lonely was associated with a nearly 60% increased risk of all-cause dementia (HR = 1.59, 95% CI = 1.51–1.65; n = 7,475 incident all-cause). In cause-specific analyses, loneliness was a stronger predictor of VD (HR = 1.82, 95% CI = 1.62–2.03; n = 1,691 incident VD) than AD (HR = 1.40, 95% CI = 1.28–1.53; n = 3135 incident AD) and was, surprisingly, a strong predictor of FTD (HR = 1.64, 95% CI = 1.22–2.20; n = 252 incident FTD). The associations were robust to sensitivity analyses and were attenuated but remained significant accounting for clinical (e.g. diabetes) and behavioral (e.g. physical activity) risk factors, depression, social isolation, and genetic risk. The association between loneliness and all-cause and AD risk was moderated by APOE ϵ4 risk status such that the increased risk was apparent in both groups but stronger among non-carriers than carriers of the risk allele.

Loneliness is associated with increased risk of multiple types of dementia.

Models of personality and health suggest that personality contributes to health outcomes across adulthood. Personality traits, such as neuroticism and conscientiousness, have long-term predictive power for cognitive impairment in older adulthood, a critical health outcome. Less is known about whether personality measured earlier in life is also associated with cognition across adulthood prior to dementia.

Using data from the British Cohort Study 1970 (N = 4218; 58% female), the current research examined the relation between self-reported and mother-rated personality at age 16 and cognitive function concurrently at age 16 and cognitive function measured 30 years later at age 46, and whether these traits mediate the relation between childhood social class and midlife cognition.

Self-reported and mother-rated conscientiousness at age 16 were each associated with every cognitive measure at age 16 and most measures at age 46. Self-reported openness was likewise associated with better cognitive performance on all tasks at age 16 and prospectively predicted age 46 performance (mothers did not rate openness). Mother-rated agreeableness, but not self-reported, was associated with better cognitive performance at both time points. Adolescent personality mediated the relation between childhood social class and midlife cognitive function.

The current study advances personality and cognition by showing that (1) adolescent personality predicts midlife cognition 30 years later, (2) both self-reports and mother-ratings are important sources of information on personality associated with midlife cognition, and (3) adolescent personality may be one pathway through which the early life socioeconomic environment is associated with midlife cognition.

Feelings of purpose and meaning in life are protective against consequential cognitive outcomes, including reduced risk of Alzheimer’s disease and dementia. Purpose and meaning are likely to also be associated with cognitive functions on the pathway to dementia. The objective of the current research was to test whether both purpose in life and meaning in life are associated with higher verbal fluency and better episodic memory and whether these associations varied by sociodemographic characteristics or economic characteristics of the country.

Prospective meta-analysis of cross-sectional associations based on individual participant data.

Established cohort studies with measures of either purpose in life or meaning in life and verbal fluency and episodic memory.

Across the cohorts, there were over 140,000 participants from 32 countries from North and South America, Europe, and the Middle East.

The meta-analysis indicated that purpose and meaning were associated with better performance on both the verbal fluency (meta-analytic partial r = .098, 95% confidence interval [CI] = .080, .116, p < .001) and episodic memory (r = .117, 95% CI = .100, .135, p < .001) task and that these associations were similar across measures of purpose in life and meaning in life. There was modest evidence that these associations were slightly stronger in relatively lower-income countries, and there was less consistent evidence that they varied by age, gender, or education.

These findings indicate a robust association between purpose/meaning and both verbal fluency and episodic memory across demographic groups and cultural context. Purpose/meaning may be a useful target of intervention for healthier cognitive aging.