Background: Good social connections have been identified as a factor that may be associated with healthy cognitive function in later life. In line with cognitive reserve theory, good social connections may provide mental stimulation through complex interaction with others and hence build cognitive reserve and maintain healthy cognitive function. However, there is considerable inconsistency in findings reported by studies that examine this association. Inconsistency in findings may be attributed to the heterogeneity of concepts potentially associated with social connections and to the variation in approaches to measuring and defining these concepts. Aims: To assess the association between aspects of social connections and cognitive function in later life. This thesis introduces a novel element by considering the moderating role of cognitive reserve in this association. Method: A scoping review was conducted to establish which concepts are used within the literature to describe social connections and how these are measured and defined. Next, a systematic review and meta-analysis was conducted to identify evidence regarding the association between social isolation and cognitive function in published studies. Empirical work was conducted using cross-sectional and longitudinal data from the Cognitive Function and Ageing Study-Wales (CFAS-Wales) to determine the associations between social isolation, cognitive reserve, and cognitive function in healthy older people. Extending this approach further, these associations were examined in two groups potentially at risk of social isolation: older people with depression or anxiety and older people living alone. Finally, empirical work was completed using the Platform for Research Online to investigate Genetics and Cognition in Ageing (PROTECT) to assess how satisfaction with social contact may be associated with cognitive function compared to a structural measure of isolation. Results: A lack of social connections was associated with poor cognitive function in later life. For people with depression or anxiety, these associations may be better explained by mood-related symptoms than social connections. People who live alone in later life were at no greater risk of poor cognitive function compared to those living with others. Satisfaction with social contact was associated with poor cognitive function but a structural measure of social isolation was not. Conclusions: Social connections play an important role in building cognitive reserve and protecting people against poor cognitive function in later life. People who are vulnerable to social isolation have different needs to those who are less vulnerable. Satisfaction with social contact is often neglected in measures that assess structural aspects of social connections but may be a better predictor of cognitive function.

Cognitive impairment is prevalent among older adults population. It brings restriction to older adults’ lives and bring huge burden to the society. Mind-body exercise has characteristics from both physical exercise and intellectual experience. Moreover, it has potential cognitive benefits to reduce the incidence even reverse cognitive impairment. Using meta-analysis to analyze findings form published research on mind-body exercise, this study will explore whether practicing mind-body exercise is beneficial for the management of cognitive impairment.

The purpose of this study was to investigate the association between extracellular basal hippocampal glutamate levels and cognitive function in epileptic patients. We used the zero-flow microdialysis method to measure the extracellular concentrations of glutamate in the epileptogenic and non-epileptogenic hippocampus of 23 awake epileptic patients during the interictal period. All patients underwent extensive neuropsychological testing to assess cognitive functioning prior to probe implantation. Basal glutamate levels in the epileptogenic hippocampus were significantly higher than the non-epileptogenic hippocampus (mean, 11.96 micromolar (µM) versus 2.92 µM, respectively). Elevated basal glutamate levels in the epileptogenic hippocampus correlated with decreased scores on the Verbal Selective Reminding Test (V-SRT) (R[exponent]2 = 0.36, p = 0.0244). When controlling for MRI-detected hippocampal atrophy within epileptogenic regions, elevated basal glutamate levels within atrophic hippocampus correlated with decreased cognitive functioning measured by both the V-SRT (R[exponent]2 = 0.7764, p = 0.0204) and Performance Intelligence Quotient (PIQ) (R[exponent]2 = 0.7324, p = 0.0297), but not within non-atrophic hippocampus (V-SRT: R2 = 0.1013, p = 0.4424; PIQ: R[exponent]2 = 0.2303, p = 0.2288). These data suggest that elevated basal glutamate levels in the epileptogenic hippocampus may be implicated in the pathogenesis of hippocampal atrophy and may contribute to impaired cognitive functioning involving verbal memory and visual-spatial skills in patients with temporal lobe epilepsy.

There is an increasing recognition that vascular disease risk is associated with a greater incidence of cognitive impairment and dementia. Such link is supported by the physiological observation that cerebral metabolism heavily relies on vascular supply of oxygen and energy substrates. Cerebral hypoperfusion which results from vascular dysfunction causes a mismatch between energy demand and supply and is associated with the pathological features of dementia, including the impairments of action potential generation and protein synthesis, glutamatergic excitotoxicity, and the deposition of cerebral amyloid-β proteins. In contrast, habitual aerobic exercise is an established strategy to ameliorate the risk factors for vascular disease and is increasingly recognized in improving cognitive function. Accordingly, the primary purpose of this dissertation study was to investigate whether the exercise-related improvement in cognitive function was attributable to ameliorated vascular function and risk factors for vascular disease. In order to address this as comprehensively as we could, both cross-sectional and interventional studies were conducted. The primary findings from the present study were as follows. In the cross-sectional study, a greater cognitive performance observed in endurance-trained adults was associated with higher levels of cerebral CO2 reactivity and brachial endothelium-dependent vasodilation and lower levels of central arterial stiffness and plasma insulin. In the interventional study, a 3-month aerobic exercise training intervention did not improve cognitive function although central arterial stiffness and brachial endothelium-dependent vasodilation made favorable changes. However, we found that the improvement in memory performance after aerobic exercise training was associated with the reduction in central systolic blood pressure. Taken together, a better cognitive performance observed in endurance-trained adults may not directly be attributable to greater vascular function because there were discrepant changes in cognitive and vascular functions after a 3-month aerobic exercise intervention. The correlation between the changes in memory performance and central systolic blood pressure is interesting but needs further investigation using a larger sample size. The discrepancy in the results between the cross-sectional and interventional studies could be explained by the duration of exercise training and/or the time it takes for the effect of improved vascular function to translate into cognitive function. / text

The incidence of stroke is increasing and is expected to continue to increase with the aging population, escalating rates of obesity and physical inactivity, and the rising prevalence of heart failure. Stroke is a leading cause of long-term disability, which includes approximately half of survivors that experience cognitive impairment. It is accepted that aerobic exercise can improve physical health in both healthy and stroke populations. Evidence also suggests aerobic exercise may positively affect cognitive function among healthy adults; however, whether there are similar beneficial effects among stroke survivors remains unclear. The purpose of this thesis was to examine whether a single session of moderate intensity aerobic exercise acutely improves cognitive function, specifically executive function, in comparison to a rest control among people with chronic stroke. Our first objective was to determine whether aerobic exercise alters cortical processing, as measured by P300 amplitude and latency during a modified Eriksen Flanker task. The second objective was to investigate whether aerobic exercise influences behavioral measures of response time and accuracy during a modified Eriksen Flanker task. Finally, the third objective was to examine the time course of effects up to 40 minutes after exercise cessation. In our sample, participants had shorter P300 latency and larger P300 amplitude 20 to 40 minutes after exercise cessation in comparison to rest. There were no significant behavioural changes. These findings suggest that aerobic exercise may enhance, or at least maintain cognitive processing speed and attention 20 to 40 minutes after exercise cessation, which otherwise deteriorated in the rest condition. Although results should be viewed cautiously due to a small sample size, these findings have potential implications for stroke rehabilitation. Our results suggest that aerobic exercise may be able to improve attentional focus during subsequent rehabilitation exercises for up to 40 minutes or more. Future research should examine whether the effects of various exercise doses and whether paired exercise and rehabilitation improves clinical outcomes.

Background: Children exposed to pesticides are susceptible for neurodevelopmental disruption. Data from developing countries are scarce. Aim: Assessing long-term and recent pesticide exposure in Nicaraguan children in relation to parental pesticide use and examining potential associated neurobehavioral effects. Methods: In the first study, pre- and post-spraying urinary residues of the chlorpyrifos metabolite TCPY and diazinon metabolite IMPY were measured among 7 subsistence farmers and 10 plantation workers, and in one child per worker. In the second study, for 110 children in an agricultural village and 22 in a non-agricultural village, aged 7-9, parental pesticide use was assessed by hours of spraying and kilograms of active ingredients during pre-and-postnatal time windows, as proxies for children’s long term pesticide exposures. Urinary TCPY, 3-PBA (pyrethroid metabolite), and 2,4-D were determined in 211 samples of 74 children of the agricultural village. IQ components and total IQ (WISC-IV) were evaluated in all agricultural village children. Behavior was evaluated with the Conners’ Teacher Rating Scale-Revised: Short. Multivariate linear regression models assessed associations between long-term and recent exposure to organophosphates and pyrethroids and cognitive and behavioral scales. Results: In study 1, post-spraying urinary levels of pesticide metabolites of subsistence farmers and their children were highly correlated (r=0.85), but not those of plantation workers and their children. In study 2, a wide range of exposures was reported by parents for all pesticides and time windows. The median urinary TCPY (3.7 μg/g creatinine), 3-PBA (2.8), and 2,4-D (0.9) were comparable to other studies for TCPY and 3-PBA but high for 2,4-D. Maximum levels were the highest reported for all compounds. Prenatal use of organophosphates affected working memory, and methamidophos also verbal comprehension and total IQ. Urinary TCPY was associated with poorer working memory. Organophosphate exposures were not associated with children’s behavior. Pyrethroid exposure during the first year of life associated with poorer perceptual reasoning and behavior, and urinary 3-PBA with a number of cognitive functions and ADHD in girls but not in boys. Conclusion: Nicaraguan children in poor agricultural areas are highly exposed to pesticides, which is influenced by parental pesticide use in subsistence farms. Organophosphate and pyrethroid exposures adversely affect their neurobehavioral development.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-17T18:38:35Z No. of bitstreams: 1 JoseEdsonDeMoura_TESE.pdf: 4337813 bytes, checksum: 465ccd15386219a1bb1458a721cdce42 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-17T20:27:42Z (GMT) No. of bitstreams: 1 JoseEdsonDeMoura_TESE.pdf: 4337813 bytes, checksum: 465ccd15386219a1bb1458a721cdce42 (MD5) / Made available in DSpace on 2017-02-17T20:27:42Z (GMT). No. of bitstreams: 1 JoseEdsonDeMoura_TESE.pdf: 4337813 bytes, checksum: 465ccd15386219a1bb1458a721cdce42 (MD5) Previous issue date: 2013-03-19 / A nutri??o tem sido considerada como um dos fatores relevantes para um bom crescimento e desenvolvimento em crian?as e adolescentes. No c?rebro, durante seu per?odo de r?pido crescimento, os micronutrientes tem apresentado um papel importante nos processos neurol?gicos, principalmente o zinco por ser um micronutriente essencial, que contribui para a forma??o da estrutura cerebral, para o desenvolvimento neuropsicol?gico e motor. Desta forma, esse micronutriente pode interferir nas fun??es cognitivas, tais como a mem?ria, aten??o, intelig?ncia, linguagem, habilidades psicomotoras e fun??es emocionais. Considerando que a literatura apresenta relatos pouco esclarecedores sobre a rela??o entre o zinco e o desenvolvimento cognitivo, principalmente em escolares, este estudo avaliou por meio da aplica??o de t?cnicas neuropsicol?gicas validadas (WISC II), o significativo papel da sua suplementa??o (5 mg/dia, durante 3 meses), na cogni??o em escolares com idade de 6 a 9 anos, sem d?ficit marginal de zinco. Os resultados mostraram que os escolares apresentaram melhores resultados ap?s o per?odo de suplementa??o, em habilidades neuropsicol?gicas especificas n?o verbal. Conclu?mos que a suplementa??o de zinco pode contribuir significativamente para o desempenho escolar. Estudos adicionais s?o necess?rios para esclarecer o impacto dessa suplementa??o em outra popula??o e com amostra mais ampla e de prefer?ncia usando o experimento duplo cego. / Zinc is an important micronutrient to human being and its deficiency among schoolchildren is deleterious to growth and development, immune competence, and cognitive function. However, the effect of zinc supplementation on cognitive function is still poorly understood. The purpose of our study was to evaluate the effect of oral zinc supplementation (5 mg Zn/d during 3 months) on Full Scale Intelligence Coefficient (FSIQ), Verbal Intelligence Quotient (VIQ), and Performance Intelligence Quotient (PIQ), using a Wechsler Intelligence Scale for Children (WISC III). We studied 36 schoolchildren, aged 6 and 9 years (7.8 ? 1.1). The tests were used in basal conditions before and after zinc supplementation. There was no difference in FSIQ by gender and age. Zinc improved VIQ, only in Information subtest (p = 0.009). But, its effects were more significant in relation to PIQ because improved the subtests Picture Completion, Picture Arrangement, Block Design and Object Assembly (p = 0.0001, for all subtests). In conclusion, zinc supplementation improved specific cognitive abilities, thereby positively influencing the academic performance of schoolchildren, even those without apparent marginal zinc deficiency.

京都大学 / 新制・課程博士 / 博士(人間健康科学) / 甲第23126号 / 人健博第88号 / 新制||人健||6(附属図書館) / 京都大学大学院医学研究科人間健康科学系専攻 / (主査)教授 稲富 宏之, 教授 若村 智子, 教授 髙橋 良輔 / 学位規則第4条第1項該当 / Doctor of Human Health Sciences / Kyoto University / DFAM

Findings on the relationship between engagement in lifestyle and cognitive functioning are not consistent; some authors report that engagement in lifestyle predicts an individual's cognitive functioning; while other report that an individual's cognitive functioning predicts the type and level of engagement an individual participates in. The current study will use longitudinal data (N = 235) to investigate the bidirectional relationship between engagement (engaged lifestyle activities) and cognition (crystallized & fluid intelligence). Despite inconsistent findings it is proposed that cognitive functioning may be better understood when examining how stimulation of activity, need for cognition, and openness to experience affect engagement in an active lifestyle. As such the current study will investigate if stimulation of activity, need for cognition, and openness to experience moderate the relationship between engaged lifestyles and cognitive functioning. The results, limitations and implications are discussed.

To better understand the impact of type 2 diabetes, the relationship between ethnicity, specifically Mexican/Mexican American ethnicity, and the disease must be further investigated. This study specifically examined the cognitive impact of type 2 diabetes. Data from the 2014 Health and Retirement Study was used to compare the cognitive functioning of non-Hispanic White (n = 10,658) and White Mexican/Mexican American (n = 847) individuals, age 50+ years, with and without type 2 diabetes. Serial 7's and immediate and delayed recall—hypothesized to be more negatively affected by type 2 diabetes and Mexican American status—was compared controlling for age, education, and depression. A multivariate analysis of covariance (MANCOVA) indicated significant main effects for race/ethnicity (F(3,11496) = 11.15, p < .001) and diabetes status (F(3,11496) = 3.15, p < .024), with Mexican Americans and those with diabetes having worse cognitive performance. There were significant effects for all covariates. A step-wise multiple regression indicated that education, age, depression, race/ethnicity and diabetes status accounted for a combined 28.4% of variance in a cognitive performance composite. Implications for assessment and treatment are discussed.