Early-life Cognitive Ability Research Articles

Childhood cognitive ability and self-harm and suicide in later life

BackgroundSelf-harm and suicide remain prevalent in later life. For younger adults, higher early-life cognitive ability appears to predict lower self-harm and suicide risk. Comparatively little is known about these associations among middle-aged and older adults. MethodsThis study examined the association between childhood (age 11) cognitive ability and self-harm and suicide risk among a Scotland-wide cohort (N = 53037), using hospital admission and mortality records to follow individuals from age 34 to 85. Multistate models examined the association between childhood cognitive ability and transitions between unaffected, self-harm, and then suicide or non-suicide death. ResultsAfter adjusting for childhood and adulthood socioeconomic conditions, higher childhood cognitive ability was significantly associated with reduced risk of self-harm among both males (451 events; HR = 0.90, 95% CI [0.82, 0.99]) and females (516 events; HR = 0.89, 95% CI [0.81, 0.98]). Childhood cognitive ability was not significantly associated with suicide risk among those with (Male: 16 events, HR = 1.05, 95% CI [0.61, 1.80]; Female: 13 events, HR = 1.08, 95% CI [0.55, 2.15]) or without self-harm events (Male: 118 events, HR = 1.17, 95% CI [0.84, 1.63]; Female: 31 events, HR = 1.30, 95% CI [0.70, 2.41]). LimitationsThe study only includes self-harm events that result in a hospital admission and does not account for self-harm prior to follow-up. ConclusionsThis extends work on cognitive ability and mental health, demonstrating that these associations can span the life course and into middle and older age.

Impact of cognitive ability in early adult life on image-based primary prevention of cardiovascular disease on among men aged 40-60 years

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): Swedish Research Council Region Västerbotten. Introduction Low early life cognitive ability is associated with high risk of CVD morbidity and mortality, and non-adherence to secondary prevention. A beneficial effect of an intervention with pictorial presentation of subclinical atherosclerosis based on ultrasonography, given to healthy participants and their physicians, resulting in lower risk of CVD after three years of follow-up, compared to only CVD risk factor assessment, was previously shown, as well as considerably higher increase of dispensing of statins. These effects were irrespective of participants’ educational level. Purpose To assess the impact of early life cognitive ability on this intervention during adult life, aiming at primary prevention av CVD, on SCORE 2 and self-reported statin medication during three years. Methods Study population: Male participants in a pragmatic RCT N=1545 (SCORE2, control 797 and intervention 748), after exclusion of men with statins at baseline N=1275 (665 and 610, respectively). Variable of interest: Cognitive ability at age 18-19 years, from the psychological testing of the Swedish Conscripts, as a modifier of the intervention. The mean of four subtests ranging from 1-9 was used. Outcome variables: SCORE2 and self-reported use of statin treatment, initiated after base-line, after three years Statistical methods: ANCOVA with SCORE2 at 3-year follow-up as dependent variable, and intervention arm, including an interaction between intervention arm and early cognitive ability, as independent variables, as well as adjustment for baseline SCORE2. Logistic regression with self-reported initiation of statin treatment as dependent variable, and intervention arm, including an interaction between intervention with early cognitive ability as independent variables. Results At baseline, there were no differences between the groups in SCORE2 and self-reported use of statins. At 3-year follow-up, mean SCORE2 for the control group and the intervention group was 7.9 and 7.7, respectively. The proportion of participants on statin treatment at 3year FU was 9.8% and 21.1%, respectively. The average treatment effect during the three years (no interaction with early cognitive ability assumed) on SCORE2 was B= -0.31 (95% CI: [-0.56, -0.05], p = 0.019) and for statin initiation OR= 2.45 (95 CI: [1.75, 3.47], p <0.001). However, no significant interactions between intervention effect and early cognitive ability was found for SCORE2 (p= 0.60) nor for initiation of statins (p= 0.17). Conclusions No heterogeneity in intervention effect due to early cognitive ability was seen. Thus, visual presentation of subclinical atherosclerosis given to healthy participants’ and their physicians demonstrated similar effect on the 10-year risk of CVD and on self-reported use of statins irrespective of early life cognitive ability. More prescriptions of statins, higher adherence to recommended statin treatment and lifestyle modifications may contribute to the intervention effects.

Education and adolescent cognitive ability as predictors of dementia in a cohort of Danish men.

BackgroundAn association between education and dementia is well-established but it is unclear whether education is associated with dementia after accounting for early life cognitive ability and whether there is a joint effect, such that the risk associated with one of the exposures depends on the value of the other. We examined separate and joint associations of adolescent cognitive ability and educational attainment with risk of dementia among Danish men born between 1939 and 1959.MethodsMen (N = 477,421) from the Danish Conscription Database were followed for dementia from the age 60 for up to 17 years via patient and prescription registry linkages. Exposure measures included cognitive ability assessed at the conscript board examination around age 18 and highest educational level (low: 0–10 year, medium: 10–13 years, high: ≥13 years) at age 30 from registry records. Associations with dementia diagnosis were estimated in Cox proportional hazards models adjusted for birth year and age at conscript board examination. Interaction was assessed on the multiplicative scale by including a product term between the two exposure measures and on the additive scale by calculating relative excess risk due to interaction (RERI) between different levels of the exposure measures.ResultsCompared to men in the high education group hazard ratio [HR] for men in the medium and low group were 1.21 (95% confidence interval [CI]: 1.13, 1.30) and 1.34 (95% CI: 1.24, 1.45), respectively when not adjusting for cognitive ability. Additional adjustment for cognitive ability attenuated the magnitude of the associations, but they remained significant (education medium: HR = 1.10, 95% CI: 1.02, 1.19 and education low: HR = 1.12, 95% CI: 1.02, 1.22). A 10% higher cognitive ability score was associated with a 3.8% lower hazard of dementia (HR = 0.962; 95% CI: 0.957, 0.967), and the magnitude of the association only changed marginally after adjustment for education. Men in the low education group with relatively low cognitive ability were identified as a high-risk subgroup for dementia. The increased risk associated with exposure to both risk factors did, however, not significantly depart from the sum of risk experienced by men only exposed to one of the risk factors (estimates of RERI were not significantly different from 0) and no significant evidence of either additive or multiplicative interactions was found.ConclusionsIn conclusion, the results suggest that education and cognitive ability protect against the risk of dementia independently of one another and that increases in educational attainment may at least partially offset dementia risk due to low cognitive ability.

Aging-Sensitive Networks Within the Human Structural Connectome Are Implicated in Late-Life Cognitive Declines

BackgroundAging-related cognitive decline is a primary risk factor for Alzheimer’s disease and related dementias. More precise identification of the neurobiological bases of cognitive decline in aging populations may provide critical insights into the precursors of late-life dementias. MethodsUsing structural and diffusion brain magnetic resonance imaging data from the UK Biobank (n = 8185; age range, 45–78 years), we examined aging of regional gray matter volumes (nodes) and white matter structural connectivity (edges) within 9 well-characterized networks of interest in the human brain connectome. In the independent Lothian Birth Cohort 1936 (n = 534; all 73 years of age), we tested whether aging-sensitive connectome elements are enriched for key domains of cognitive function before and after controlling for early-life cognitive ability. ResultsIn the UK Biobank, age differences in individual connectome elements corresponded closely with principal component loadings reflecting connectome-wide integrity (|rnodes| = .420; |redges| = .583), suggesting that connectome aging occurs on broad dimensions of variation in brain architecture. In the Lothian Birth Cohort 1936, composite indices of node integrity were predictive of all domains of cognitive function, whereas composite indices of edge integrity were associated specifically with processing speed. Elements within the central executive network were disproportionately predictive of late-life cognitive function relative to the network’s small size. Associations with processing speed and visuospatial ability remained after controlling for childhood cognitive ability. ConclusionsThese results implicate global dimensions of variation in the human structural connectome in aging-related cognitive decline. The central executive network may demarcate a constellation of elements that are centrally important to age-related cognitive impairments.

An epigenetic predictor of death captures multi-modal measures of brain health

Individuals of the same chronological age exhibit disparate rates of biological ageing. Consequently, a number of methodologies have been proposed to determine biological age and primarily exploit variation at the level of DNA methylation (DNAm). A novel epigenetic clock, termed ‘DNAm GrimAge’ has outperformed its predecessors in predicting the risk of mortality as well as many age-related morbidities. However, the association between DNAm GrimAge and cognitive or neuroimaging phenotypes remains unknown. We explore these associations in the Lothian Birth Cohort 1936 (n = 709, mean age 73 years). Higher DNAm GrimAge was strongly associated with all-cause mortality over the eighth decade (Hazard Ratio per standard deviation increase in GrimAge: 1.81, P < 2.0 × 10−16). Higher DNAm GrimAge was associated with lower age 11 IQ (β = −0.11), lower age 73 general cognitive ability (β = −0.18), decreased brain volume (β = −0.25) and increased brain white matter hyperintensities (β = 0.17). There was tentative evidence for a longitudinal association between DNAm GrimAge and cognitive decline from age 70 to 79. Sixty-nine of 137 health- and brain-related phenotypes tested were significantly associated with GrimAge. Adjusting all models for childhood intelligence attenuated to non-significance a small number of associations (12/69 associations; 6 of which were cognitive traits), but not the association with general cognitive ability (33.9% attenuation). Higher DNAm GrimAge associates with lower cognitive ability and brain vascular lesions in older age, independently of early-life cognitive ability. This epigenetic predictor of mortality associates with different measures of brain health and may aid in the prediction of age-related cognitive decline.

Early-life cognitive ability and recovery from stroke

Background In ageing populations it is increasingly important to understand what contributes to health and wellbeing in later life. Older adults in particular are prone to function-limiting health issues which impair their ability to be productive and live independently. The incidence of stroke – one of the most common morbidities among older adults – has been shown to be predicted by early-life cognitive ability, such that those with higher cognitive ability are at lower risk. However, less is known about the role that early-life cognitive ability plays in recovery from stroke.&#x0D; Aim Investigate the association between early-life circumstances, particularly cognitive ability, and later-life recovery from stroke.&#x0D; Methods Using a large sample of individuals born in Scotland in 1936, historic data from the Scottish Mental Survey 1947 will be linked to administrative and healthcare records from across the life course. Incidence of stroke can be identified using healthcare records prior to 2011, and later functional outcomes will be extracted from the Scottish Stroke Care Audit and from Scottish Censuses 2001 and 2011.&#x0D; Analysis Multiple regression models will be used to examine associations between early-life variables and changes in post-morbid general health and physical function among those experiencing stroke prior to 2011. Time since morbidity, number of morbidity events prior to follow-up, and severity of morbidity will be included as covariates. Analyses will be stratified by type of stroke to account for heterogeneity in aetiology, and recovery profiles will be compared between different types of stroke where possible.

Childhood cognitive ability and the use of long-term care in later life

Background As the population ages the demand for care is predicted to increase. Previous studies have reported that individuals with poorer post-morbid cognitive ability are at higher risk of entering long-term care, both institutionalised care and home-based care. Given that post-morbid cognitive ability is sensitive to the type and severity of morbidity, it remains unclear whether higher cognitive ability, as a trait-level measure of individual differences, contributes to care usage. Some success has been observed using non-cognitive early-life circumstances such as socioeconomic circumstances as pre-morbid predictors of care risk. However, the contribution of early-life cognitive ability has yet to be examined.&#x0D; Main Aim We investigate the association between early-life circumstances, particularly cognitive ability, and the risk of entry into long-term care in later life (age 65+).&#x0D; Methods Veterans were identified using the South London and Maudsley Biomedical Research Centre (SLaM) case register – a database holding secondary mental health care electronic records for the South London and Maudsley National Health Service Trust of 300,000 patients. We developed two methods. An NLP and machine learning tool were developed to automatically evaluate personal history statements written by clinicians.&#x0D; Results This study uses a large sample of individuals born in Scotland in 1936 and who took part in the Scottish Mental Survey 1947. It links research data from childhood to routinely-collected administrative and healthcare records from across the life course.&#x0D; Conclusion We demonstrate the importance of early-life factors for predicting care usage in later life and how this role differs between types of long-term care. The implications of the results for research and policy will be discussed.

S59DELINEATING TCF4 GENETIC NETWORKS IN SCHIZOPHRENIA AND DEPRESSION

We examined the association between cognitive ability in young adulthood and dementia in Danish men, brothers, and male twins.In total, 666,986 men born between 1939 and 1959 were identified for dementia diagnosis in national registries from 1969 to 2016. The association between cognitive ability from draft board examination and dementia was examined using Cox regression.During a 44-year follow-up, 6416 (0.96%) men developed dementia, 1760 (0.26%) and 970 (0.15%) of which were classified as Alzheimer's and vascular dementia, respectively. Low cognitive ability was associated with increased risk of dementia (hazard ratio [HR]per SD decrease 1.33 [95% confidence interval {CI} = 1.30–1.35]) with the strongest associations for vascular dementia (HRper SD decrease 1.47 [95% CI = 1.31–1.56]) and a weaker for Alzheimer's disease (HRper SD decrease 1.07 [95% CI = 1.03–1.13]). The intrabrother and twin analyses (taking shared family factors into account) showed attenuated risk estimates but with wide CIs.Low early-life cognitive ability increases the risk of dementia before the age of 78 years. The association is partly explained by shared family factors.

Longitudinal associations between hearing loss and general cognitive ability: The Lothian Birth Cohort 1936.

Hearing impairment is associated with poorer cognitive function in later life. We tested for the potential contribution of childhood cognitive ability to this relationship. Childhood cognitive ability is strongly related to cognitive function in older age, and may be related to auditory function through its association with hearing impairment risk factors. Using data from the Lothian Birth Cohort, 1936, we tested whether childhood cognitive ability predicted later-life hearing ability then whether this association was mediated by demographic or health differences. We found that childhood cognitive ability was negatively associated with hearing impairment risk at age 76 (odds ratio = .834, p = .042). However, this association was nonsignificant after subsequent adjustment for potentially mediating demographic and health factors. Next, we tested whether associations observed in older age between hearing impairment and general cognitive ability level or change were accounted for by childhood cognitive ability. At age 76, in the minimally adjusted model, hearing impairment was associated with poorer general cognitive ability level (β = −.119, p = .030) but was not related to decline in general cognitive ability. The former association became nonsignificant after additional adjustment for childhood cognitive ability (β = −.068, p = .426) suggesting that childhood cognitive ability contributes (potentially via demographic and health differences) to the association between levels of hearing and cognitive function in older age. Further work is needed to test whether early life cognitive ability also contributes to the association (documented in previous studies) between older-age hearing impairment and cognitive decline.

Theory of mind and psychosocial characteristics in older men.

The extent to which early-life cognitive ability shapes individuals’ social functioning throughout life, in the context of later-life factors, is unknown. We investigated performance on the Faux Pas test (FP) in relation to psychosocial characteristics and childhood intelligence scores in 90 healthy older men. FP performance was associated with close social network size but not social contact, social support, or loneliness when accounting for both childhood and later-life intelligence, affect, personality, and sociodemography. We add to a growing literature on associations between theory of mind and intelligence, affect, and personality.

Adolescent Cognitive Aptitudes and Later-in-Life Alzheimer Disease and Related Disorders

Low early-life cognitive ability is a potential early marker of dementia risk in later life. Previous studies use only global measures of general intelligence and/or study this relationship in gender-specific samples. The contribution of early-life performance on specific cognitive abilities, such as language, reasoning, and visualization aptitudes, to indicating future dementia risk is unknown. To investigate the association between adolescent cognitive ability and Medicare-recorded Alzheimer disease and related disorders (ADRD) using both general and specific measures of cognitive ability and to explore these associations separately in men and women. Population-based cohort study from the Project Talent-Medicare linked data set, a linkage of adolescent sociobehavioral data collected from high school students in 1960 to participants' 2012 to 2013 Medicare Claims and expenditures data. The association between adolescent cognitive ability and risk of ADRD in later life was assessed in a diverse sample of 43 014 men and 42 749 women aged 66 to 73 years using a series of logistic regressions stratified by sex, accounting for demographic characteristics, adolescent socioeconomic status, and regional effects. Data analysis was conducted from November 2017 to March 2018. Presence of Medicare-reported ADRD. Overall, 1239 men (2.9%) and 1416 women (3.3%) developed ADRD. Lower mechanical reasoning was associated with increased odds of ADRD in men (odds ratio, 1.17; 95% CI, 1.05-1.29), and lower memory for words in adolescence was associated with increased odds of ADRD in women (odds ratio, 1.16; 95% CI, 1.05-1.28). Lower performance on several other language, reasoning, visualization, and mathematic aptitudes in adolescence showed prominent, but weaker, associations with odds of ADRD. This work contributes to the understanding of early-life origins of ADRD risk. The results suggest specific measures of cognitive ability may contribute to very early identification of at-risk subgroups who may benefit from prevention or intervention efforts.

Higher IQ in adolescence is related to a younger subjective age in later life: Findings from the Wisconsin Longitudinal Study

Subjective age predicts consequential outcomes in old age, including risk of hospitalization, dementia, and mortality. Studies investigating the determinants of subjective age have mostly focused on aging-related factors measured in adulthood and old age. Little is known about the extent to which early life factors may contribute to later life subjective age. The present study examined the prospective association between IQ in adolescence and subjective age in later life and tested education, disease burden, adult cognition, and personality traits as potential mediators. Participants (N = 4494) were drawn from the Wisconsin Longitudinal Study. Data on IQ were obtained in 1957 when participants were in high school. Education, disease burden, cognition, and personality were assessed in 1992–1993, and subjective age was measured in 2011 at age 71 (SD = 0.93). Accounting for demographic factors, results revealed that higher IQ in adolescence was associated with a younger subjective age in late life. Bootstrap analysis further showed that this association was mediated by higher openness. The present study suggests that how old or young individuals feel is partly influenced by lifespan developmental processes that may begin with early life cognitive ability.

Early Life Determinants of Cognitive Ability: A Comparative Study on Madagascar and Senegal

We study the determinants of educational and cognitive outcomes of young adults in Madagascar and Senegal employing a production function approach. Using unique and comparable long-term panel data sets from both countries, we find that cognitive skills measured using test scores in second grade are strong predictors of school attainment and cognitive skills of a cohort of individuals surveyed in their early twenties. The inclusion of early life household wealth, parental education and other household characteristics in the model does not diminish the impact of early cognitive ability on educational and cognitive outcomes in young adult life. Additionally, we find that both early life cognitive ability and health seem to have independent effects on educational attainment and adult cognition. In Senegal, both math and French scores are strong predictors of adult cognitive skills, whereas in Madagascar math plays a relatively stronger role. We find suggestive evidence that the association between early life cognitive ability and later life outcomes is stronger among girls as compared to boys. We also show significant differences in the relationship between early ability and later life test scores for those cohort members according to their height, which we consider a proxy for health status – shorter individuals show a stronger relationship between second grade performance and later life outcomes. These findings highlight the importance of how falling behind in early life may be critical in determining longterm outcomes, particularly for vulnerable groups, that is girls and shorter individuals.

Wastage of talent?

Abstract The extent to which societies suffer ‘wastage of talent’ due to social inequalities in educational attainment is a longstanding issue. The present paper contributes to the relevant literature by examining how social origins and early-life cognitive ability are associated with educational success across three British birth cohorts. We address questions of over-time change, bringing current evidence up-to-date. Our findings reinforce the well-established trend that the importance of cognitive ability declined for cohorts born between 1958 and 1970, but we show that for a cohort born in the early 1990s this trend has reversed. We further show that the relative importance of family background has not seen a corresponding decline. In distinguishing between different components of social origins, we show that family economic resources have become somewhat less important for children’s educational success, while socio-cultural and educational resources have become more important. Even high ability children are unable to transcend the effects of their social origins. The problem of ‘wastage of talent’ remains; young people from disadvantaged backgrounds are still lacking the opportunity to fully realise their potential within the British educational system.

Cognitive ability in young adulthood and risk of dementia in a cohort of Danish men, brothers, and twins

IntroductionWe examined the association between cognitive ability in young adulthood and dementia in Danish men, brothers, and male twins. MethodsIn total, 666,986 men born between 1939 and 1959 were identified for dementia diagnosis in national registries from 1969 to 2016. The association between cognitive ability from draft board examination and dementia was examined using Cox regression. ResultsDuring a 44-year follow-up, 6416 (0.96%) men developed dementia, 1760 (0.26%) and 970 (0.15%) of which were classified as Alzheimer's and vascular dementia, respectively. Low cognitive ability was associated with increased risk of dementia (hazard ratio [HR]per SD decrease 1.33 [95% confidence interval {CI} = 1.30–1.35]) with the strongest associations for vascular dementia (HRper SD decrease 1.47 [95% CI = 1.31–1.56]) and a weaker for Alzheimer's disease (HRper SD decrease 1.07 [95% CI = 1.03–1.13]). The intrabrother and twin analyses (taking shared family factors into account) showed attenuated risk estimates but with wide CIs. DiscussionLow early-life cognitive ability increases the risk of dementia before the age of 78 years. The association is partly explained by shared family factors.

Childhood Cognitive Ability and Incident Dementia: The 1932 Scottish Mental Survey Cohort into their 10th Decade.

The prevention of dementia is a global priority but its etiology is poorly understood. Early life cognitive ability has been linked to subsequent dementia risk but studies to date have been small and none has examined sex differences. In the 1932 Scottish Mental Survey cohort, we related intelligence test scores at age 11 years in 16,370 boys and 16,097 girls (born in 1921) to incident dementia ages ≥65 years as ascertained using probabilistic linkage to electronic health records up to the age of 92 years (1,231 cases in men, 2,163 in women; median follow-up 15 years). Compared with the highest intelligence group (IQ ≥115), dementia risk was raised in the lowest-scoring category (<85) and these associations were stronger for women (hazard ratio; 95% confidence interval: 1.51; 1.29, 1.76) than men (1.19; 0.98, 1.44; P value for interaction by gender: 0.054). There was evidence of a dose-response association between childhood IQ and dementia in women (IQ 100-114.9 compared with ≥115: 1.18; 1.03, 1.34; IQ 85-99.9: 1.32; 1.15, 1.51; P value for trend <0.001) but not in men (1.05; 0.89, 1.24 and 1.01; 0.85, 1.21; 0.44). Childhood intelligence is related to subsequent dementia risk but this association is not the same in men and women. See video abstract at, http://links.lww.com/EDE/B184.

Do early life cognitive ability and self-regulation skills explain socio-economic inequalities in academic achievement? An effect decomposition analysis in UK and Australian cohorts

Socio-economic inequalities in academic achievement emerge early in life and are observed across the globe. Cognitive ability and “non-cognitive” attributes (such as self-regulation) are the focus of many early years’ interventions. Despite this, little research has compared the contributions of early cognitive and self-regulation abilities as separate pathways to inequalities in academic achievement. We examined this in two nationally representative cohorts in the UK (Millennium Cohort Study, n = 11,168; 61% original cohort) and Australia (LSAC, n = 3028; 59% original cohort).An effect decomposition method was used to examine the pathways from socio-economic disadvantage (in infancy) to two academic outcomes: ‘low’ maths and literacy scores (based on bottom quintile) at age 7–9 years. Risk ratios (RRs, and bootstrap 95% confidence intervals) were estimated with binary regression for each pathway of interest: the ‘direct effect’ of socio-economic disadvantage on academic achievement (not acting through self-regulation and cognitive ability in early childhood), and the ‘indirect effects’ of socio-economic disadvantage acting via self-regulation and cognitive ability (separately). Analyses were adjusted for baseline and intermediate confounding.Children from less advantaged families were up to twice as likely to be in the lowest quintile of maths and literacy scores. Around two-thirds of this elevated risk was ‘direct’ and the majority of the remainder was mediated by early cognitive ability and not self-regulation. For example in LSAC: the RR for the direct pathway from socio-economic disadvantage to poor maths scores was 1.46 (95% CI: 1.17–1.79). The indirect effect of socio-economic disadvantage through cognitive ability (RR = 1.13 [1.06–1.22]) was larger than the indirect effect through self-regulation (1.05 [1.01–1.11]). Similar patterns were observed for both outcomes and in both cohorts.Policies to alleviate social inequality (e.g. child poverty reduction) remain important for closing the academic achievement gap. Early interventions to improve cognitive ability (rather than self-regulation) also hold potential for reducing inequalities in children's academic outcomes.

Occupational complexity and lifetime cognitive abilities

Objective:To examine associations between complexity of main lifetime occupation and cognitive performance in later life.Methods:Occupational complexity ratings for data, people, and things were collected from the Dictionary of Occupational Titles for 1,066 individuals (men = 534, women = 532) in the Lothian Birth Cohort 1936. IQ data were available from mean age 11 years. Cognitive ability data across the domains of general ability, processing speed, and memory were available at mean age 70 years.Results:General linear model analyses indicated that complexity of work with people and data were associated with better cognitive performance at age 70, after including age 11 IQ, years of education, and social deprivation.Conclusions:The current findings are supportive of the differential preservation hypotheses that more stimulating environments preserve cognitive ability in later life, although the continued effects into old age are still debated. Studies that have early-life cognitive ability measures are rare, and the current study offers interesting prospects for future research that may further the understanding of successful aging.

The effects of social origins and cognitive ability on educational attainment

In previous work we have shown that in Britain and Sweden alike parental class, parental status and parental education have independent effects on individuals’ educational attainment. In this paper we extend our analyses, first by also including measures of individuals’ early-life cognitive ability, and second by bringing our results for Britain and Sweden into direct comparative form. On the basis of extensive birth-cohort data for both countries, we find that when cognitive ability is introduced into our analyses, parental class, status and education continue to have significant, and in fact only moderately reduced and largely persisting, effects on the educational attainment of members of successive cohorts. There is some limited evidence for Britain, but not for Sweden, that cognitive ability has a declining effect on educational attainment, and a further cross-national difference is that in Britain, but not in Sweden, some positive interaction effects occur between advantaged social origins and high cognitive ability in relation to educational success. Overall, though, cross-national similarities are most apparent, and especially in the extent to which parental class, status and education, when taken together, create wide disparities in the eventual educational attainment of individuals who in early life were placed at similar levels of cognitive ability. Some wider implications of these findings are considered.