The genetic basis of spatial cognitive variation in a food-caching bird

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Genome-wide quantitative trait locus association scan of general cognitive ability using pooled DNA and 500K single nucleotide polymorphism microarrays

General cognitive ability ( g ), which refers to what cognitive abilities have in common, is an important target for molecular genetic research because multivariate quantitative genetic analyses have shown that the same set of genes affects diverse cognitive abilities as well as learning disabilities. In this first autosomal genome-wide association scan of g , we used a two-stage quantitative trait locus (QTL) design with pooled DNA to screen more than 500 000 single nucleotide polymorphisms (SNPs) on microarrays, selecting from a sample of 7000 7-year-old children. In stage 1, we screened for allele frequency differences between groups pooled for low and high g . In stage 2, 47 SNPs nominated in stage 1 were tested by individually genotyping an independent sample of 3195 individuals, representative of the entire distribution of g scores in the full 7000 7-year-old children. Six SNPs yielded significant associations across the normal distribution of g , although only one SNP remained significant after a false discovery rate of 0.05 was imposed. However, none of these SNPs accounted for more than 0.4% of the variance of g , despite 95% power to detect associations of that size. It is likely that QTL effect sizes, even for highly heritable traits such as cognitive abilities and disabilities, are much smaller than previously assumed. Nonetheless, an aggregated 'SNP set' of the six SNPs correlated 0.11 ( P  < 0.00000003) with g . This shows that future SNP sets that will incorporate many more SNPs could be useful for predicting genetic risk and for investigating functional systems of effects from genes to brain to behavior.     

Development and heritability of subcortical brain volumes at ages 9 and 12

Subcortical brain structures are involved in a variety of cognitive and emotional functions and follow different trajectories of increase and decrease in volume from childhood to adulthood. The heritability of development of subcortical brain volumes during adolescence has not been studied comprehensively. In a longitudinal twin study, we estimated to what extent subcortical brain volumes are influenced by genetic factors at ages 9 and 12. In addition, we assessed whether new genes are expressed at age 12 and whether there is evidence for genotype by sex interaction. Brain scans were acquired for 112 and 89 twin pairs at 9 and 12 years of age. In both boys and girls, there was an increase in volumes of the thalamus, hippocampus, amygdala and pallidum, and a decrease in volumes of the caudate and nucleus accumbens. The putamen showed a decrease in boys bilaterally and an increase in girls in the left hemisphere. Heritability was high (>50%) for all structures – except for the left nucleus accumbens – with heritabilities ranging from 0.50 to 0.91 at age 9, and from 0.59 to 0.88 at age 12. There were no significant new genetic effects coming into play at age 12, and there was no evidence for genotype by sex interactions. These findings suggest that despite their sensitivity to environmental effects, the heritability of subcortical brain structures is high from childhood on, resembling estimates found in adult samples.     

Powerful allies: Arts educators and early childhood educators joining forces on behalf of young children

ABSTRACT

Arts educators and early childhood educators espouse similar philosophies and purposes surrounding young children's educational lives, yet continue to function in largely separate worlds. This article calls for the creation of intentional alliances between the two disciplines, by first recognizing and embracing these alignments. In addition, this article provides recommendations for arts educators and early childhood educators to consider as they join forces to ensure that all young children have access to high-quality arts-based education.     

Amplification dynamics of miniature inverted-repeat transposable elements and their impact on rice trait variability

Transposable elements (TEs) are a rich source of genetic variability. Among TEs, miniature inverted-repeat TEs (MITEs) are of particular interest as they are present in high copy numbers in plant genomes and are closely associated with genes. MITEs are deletion derivatives of class II transposons, and can be mobilized by the transposases encoded by the latter through a typical cut-and-paste mechanism. However, MITEs are typically present at much higher copy numbers than class II transposons. We present here an analysis of 103 109 transposon insertion polymorphisms (TIPs) in 738 Oryza sativa genomes representing the main rice population groups. We show that an important fraction of MITE insertions has been fixed in rice concomitantly with its domestication. However, another fraction of MITE insertions is present at low frequencies. We performed MITE TIP-genome-wide association studies (TIP-GWAS) to study the impact of these elements on agronomically important traits and found that these elements uncover more trait associations than single nucleotide polymorphisms (SNPs) on important phenotypes such as grain width. Finally, using SNP-GWAS and TIP-GWAS we provide evidence of the replicative amplification of MITEs.     

The effect of dietary docosahexaenoic acid on schooling behaviour and brain development in larval yellowtail

The onset of schooling behaviour and brain growth in larval yellowtail Seriola quinqueradiata larvae fed on Artemia enriched with oleic acid (OA), eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) for 10 days was investigated. Larvae from the DHA groups schooled with parallel orientation while those of the EPA groups showed only aggregation. Larvae of the OA groups were dispersed. DHA and EPA groups showed significantly smaller nearest neighbour distance compared with OA groups, and DHA groups showed significantly smaller values of nearest neighbour angle compared with the other groups. The relative volume of the tectum opticus (TO) of the DHA group was significantly larger in two experiments and also the relative volume of the cerebellum (CE) of that group was significantly larger in one experiment. Dietary DHA is probably critically important for the development of the brain, particularly TO, during the larval stages, and that development of TO may be the key factor of the ontogeny of schooling behaviour.     

The eugenics movement and its impact on art education in the United States

This article argues that the eugenics movement has had three major influences on education in the United States, and reveals how these influences have had an impact on visual arts education in particular. The first influence began with a debate between John Dewey and David Snedden that resulted in a two-tiered tracking system that separated college bound and vocational students. The second is the influence of eugenics on the establishment of the hierarchical framework for the public school curriculum. The third influence of eugenics discussed in this article is its impact on standardized testing. These influences have justified American imperialism in schools, and have led to the marginalization of visual arts education in the United States.     

The impact of anxiety-inducing distraction on cognitive performance: a combined brain imaging and personality investigation

Background

Previous investigations revealed that the impact of task-irrelevant emotional distraction on ongoing goal-oriented cognitive processing is linked to opposite patterns of activation in emotional and perceptual vs. cognitive control/executive brain regions. However, little is known about the role of individual variations in these responses. The present study investigated the effect of trait anxiety on the neural responses mediating the impact of transient anxiety-inducing task-irrelevant distraction on cognitive performance, and on the neural correlates of coping with such distraction. We investigated whether activity in the brain regions sensitive to emotional distraction would show dissociable patterns of co-variation with measures indexing individual variations in trait anxiety and cognitive performance.

Methodology/Principal Findings

Event-related fMRI data, recorded while healthy female participants performed a delayed-response working memory (WM) task with distraction, were investigated in conjunction with behavioural measures that assessed individual variations in both trait anxiety and WM performance. Consistent with increased sensitivity to emotional cues in high anxiety, specific perceptual areas (fusiform gyrus - FG) exhibited increased activity that was positively correlated with trait anxiety and negatively correlated with WM performance, whereas specific executive regions (right lateral prefrontal cortex - PFC) exhibited decreased activity that was negatively correlated with trait anxiety. The study also identified a role of the medial and left lateral PFC in coping with distraction, as opposed to reflecting a detrimental impact of emotional distraction.

Conclusions

These findings provide initial evidence concerning the neural mechanisms sensitive to individual variations in trait anxiety and WM performance, which dissociate the detrimental impact of emotion distraction and the engagement of mechanisms to cope with distracting emotions. Our study sheds light on the neural correlates of emotion-cognition interactions in normal behaviour, which has implications for understanding factors that may influence susceptibility to affective disorders, in general, and to anxiety disorders, in particular.     

The importance of boron nutrition for brain and psychological function

Boron (B) nutriture has been related to bone, mineral and lipid metabolism, energy utilization, and immune function. As evidence accumulates that B is essential for humans, it is important to consider possible relationships between B nutriture and brain and psychological function. Five studies conducted in our laboratory are reviewed. Assessments of brain electrical activity in both animals and humans found that B deprivation results in decreased brain electrical activity similar to that observed in nonspecific malnutrition. Assessments of cognitive and psychomotor function in humans found that B deprivation results in poorer performance on tasks of motor speed and dexterity, attention, and short-term memory. However, little support was found for anecdotal reports that supplementation with physiologic amounts of B helps alleviate the somatic and psychological symptoms of menopause. Parallels between nutritional and toxicological effects of B on brain and psychological function are presented, and possible biological mechanisms for dietary effects are reviewed. Findings support the hypothesis that B nutriture is important for brain and psychological function in humans. Mention of a trademark or proprietary product does not constitute a guarantee or warranty of the product by the US Department of Agriculture and does not imply its approval to the exclusion of other products that may also be suitable. The US Department of Agriculture, Agricultural Research Service, Northern Plains Area, is an equal opportunity/affirmative action employer, and all agency services are available without discrimination.     

年轻小鼠咀嚼刺激长期改变对焦虑和认知的影响

建立长期增加或减少年轻小鼠切牙的咀嚼刺激模型.通过形态学的观察,研究小鼠下颌骨和咬肌的变化以及大脑皮层和海马的厚度改变;通过行为学实验(旷场实验、高架十字迷宫、新异物体识别和Morris水迷宫实验)观察小鼠认知能力和焦虑情绪的变化;通过高效液相色谱(HPLC)检测小鼠皮层、海马中4种单胺类神经递质(去甲肾上腺素(NE)、肾上腺素(E)、多巴胺(DA)和5-羟色胺(5-HT))的变化,以探讨小鼠焦虑情绪改变的机理;通过荧光实时定量PCR检测小鼠皮层和海马与认知紧密相关的4种基因(BDNF、Synapsin I、NR2B和CREB)的mRNA表达,以研究小鼠认知能力改变的机理.形态学结果显示:各组小鼠下颌骨和咬肌纤维的形态没有影响,各组小鼠皮层和海马的厚度也没有差异.行为学实验结果显示:咀嚼增加组小鼠焦虑倾向低于对照组和咀嚼减少组,各组小鼠短期记忆能力没有统计学差异,咀嚼增加组小鼠空间认知能力优于咀嚼减少组.高效液相色谱结果显示,咀嚼减少组小鼠与咀嚼增加组和对照组相比,去甲肾上腺素在皮层中明显升高(P<0.05).mRNA检测结果显示,咀嚼减少组小鼠4种与认知相关基因的表达量与咀嚼增加组相比都明显下调(P<0.05).上述结果提示,切牙咀嚼刺激的长期增加可以提高小鼠的自主运动能力,降低焦虑程度,提高空间认知能力,上调海马中认知相关基因的表达.切牙咀嚼刺激的长期减少,会降低小鼠的自主运动能力,下调认知相关的基因表达,增加大脑皮层中去甲肾上腺素的含量.     

The influence of complex and threatening environments in early life on brain size and behaviour

The ways in which challenging environments during development shape the brain and behaviour are increasingly being addressed. To date, studies typically consider only single variables, but the real world is more complex. Many factors simultaneously affect the brain and behaviour, and whether these work independently or interact remains untested. To address this, zebrafish (Danio rerio) were reared in a two-by-two design in housing that varied in structural complexity and/or exposure to a stressor. Fish experiencing both complexity (enrichment objects changed over time) and mild stress (daily net chasing) exhibited enhanced learning and were less anxious when tested as juveniles (between 77 and 90 days). Adults tested (aged 1 year) were also less anxious even though fish were kept in standard housing after three months of age (i.e. no chasing or enrichment). Volumetric measures of the brain using magnetic resonance imaging (MRI) showed that complexity alone generated fish with a larger brain, but this increase in size was not seen in fish that experienced both complexity and chasing, or chasing alone. The results highlight the importance of looking at multiple variables simultaneously, and reveal differential effects of complexity and stressful experiences during development of the brain and behaviour.     

The effects of maternal education versus cognitive test scores on child nutrition in Kenya

This paper estimates dynamic random effects models for intakes by dietary energy, protein, calcium, iron, zinc, niacin, riboflavin, thiamin, and vitamins A, C, D, and E 100 of Kenyan school children (6-9 years) within a multivariate longitudinal framework. The explanatory variables were socioeconomic and background variables, children's body mass index, and maternal education, cognitive test scores and morbidity spells. The model parameters are estimated using the maximum likelihood method controlling for unobserved between-children differences. The main finding is that while maternal education was usually not a significant predictor of dietary intakes, maternal scores on cognitive tests did strongly predict them. Moreover, the paternal cognitive scores and maternal morbidity levels were not significantly associated with the intakes, but an index of socioeconomic status and cash income was a significant predictor. The results indicate the need to consider broader measures of human development and of devising suitable educational programs for women without formal education.     

青年教师卓越教学能力的提升对留学生人体解剖与组织胚胎学教学的影响

高校留学生教育迅速发展,我国高校青年教师教学能力的发展还存在诸多问题,"卓越计划"背景下高校青年教师的留学生教学能力亟待提高。根据我校青年教师的发展特点以及留学生教学现状,我们通过组织精彩示范课、教师系列培训等活动以及加强基础教师实践能力培养等一系列措施,形成了一套切实可行的提高青年教师人体解剖与组织胚胎学教学能力的有效策略。经过统计分析发现,教学效果显著提高。     

The brain cognitive reserve hypothesis: A review with emphasis on the contribution of nuclear medicine neuroimaging techniques

Neuropathological and clinical evidence indicates that the clinical expression of Alzheimer's disease (AD) occurs as neuropathology exceeds the brain reserve capacity. The brain or cognitive reserve (BCR) hypothesis states that high premorbid intelligence, education, and an active and stimulating lifestyle provide reserve capacity, which acts as a buffer against the cognitive deficits due to accumulating neuropathology. Neuroimaging studies that assessed the BCR hypothesis are critically reviewed with emphasis on study design and statistical analysis. Many studies were performed in the last two decades owing to the increasing availability of positron emission tomography (PET) and PET/computed tomography scanners and to the synthesis of new radiopharmaceuticals, including tracers for amyloid and tau proteins. Studies with different tracers provided complementary consistent results supporting the BCR hypothesis. Many studies were appropriately designed with a measure of reserve, a measure of brain anatomy/function/neuropathology, and a measure of cognitive functions that are necessary. Most of the early studies were performed with PET and [ ¹⁸F]fluorodeoxyglucose, and occasionally with [ ¹⁵O]water, reporting a significant association between higher occupation/education and lower glucose metabolism (blood flow) in associative temporo-parietal cortex in patients with AD and also in patients with MCI, after correcting for the degree in the cognitive impairment. On the contrary, performances on several neuropsychological tests increased with increasing education for participants with elevated [ ¹¹C]PiB uptake. Studies with the tracers specific for tau protein showed that patients with AD with elevated tau deposits had higher cognitive performances compared with patients with similar levels of tau deposits. BCR in AD is also associated with a preserved cholinergic function. The BCR hypothesis has been validated with methodologically sound study designs and sophisticated neuroimaging techniques using different radiotracers and providing an explanation for neuropathological and clinical observations on patients with AD.     

The single-cell and spatial transcriptional landscape of human gastrulation and early brain development

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Analysis of organelles within the nervous system: impact on brain and organelle functions

Currently, neuroproteomic approaches aimed at the profiling of total brain areas generally mirror the expression of the most abundant proteins, but fail to uncover less abundant proteins. By contrast, the focus on typical brain subproteomes, (e.g., synaptic vesicles, synaptic terminal membranes or the postsynaptic density), may give a more specific insight into brain function. Subproteomes are accessible via several strategies, including subcellular fractionation or affinity-based pull-down approaches. Combined with mass spectrometric quantification approaches, subcellular proteomics is expected to reveal differences in the protein constitution of related cellular organelles. Focusing on novel functions and mechanistic models, we review recent data on the analysis of brain-derived organelles and subproteomes, including presynaptic termini, synaptic vesicles, neuronal plasma membranes, postsynaptic density and neuromelanin granules, which were identified as novel lysosome-related organelles within the human brain.     

Studies on brain volume, Alzheimer-related proteins and cytokines in mice with chronic overexpression of IL-1 receptor antagonist

Inflammation is associated with both acute and chronic neurological disorders, including stroke and Alzheimer's disease (AD). Cytokines such as interleukin (IL)-1 have several activities in the brain both under physiological and pathophysiological conditions. The objective of this study was to evaluate consequences of the central blockade of IL-1 transmission in a previously developed transgenic mouse strain with brain-directed overexpression of human soluble IL-1 receptor antagonist (Tg hsIL-1ra). Effects on brain morphology and brain levels of the AD-related proteins beta-amyloid precursor protein (APP) and presenilin 1(PS1), as well as the levels of IL-1beta, IL-6 and tumour necrosis factor-alpha (TNF-alpha) were analysed in homozygotic and heterozygotic mice and wild type (WT) controls, of both genders and of young (30-40 days) and adult (13-14 months) age. A marked reduction in brain volume was observed in transgenic mice as determined by volumetry. Western blot analysis showed higher levels of APP, but lower levels of PS1, in adult animals than in young ones. In the cerebellum, heterozygotic (Tg hsIL-1ra(+/-)) mice had lower levels of APP and PS1 than WT mice. With one exception, there were no genotypic differences in the levels of IL-1beta, IL-6 and TNF-alpha. The cytokine levels were generally higher in adult than in young mice. In conclusion, the chronic blockade of IL-1 signalling in the brain was associated with an atrophic phenotype of the brain, and with modified levels of APP and PS1. Brain-directed overexpression of hsIL-1ra was not followed by major compensatory changes in the levels of pro-inflammatory cytokines.