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Etiology of Inattention and Hyperactivity/Impulsivity in a Community Sample of Twins with Learning Difficulties 总被引:3,自引:0,他引:3
A community sample of 373 8 to 18 year-old twin pairs in which at least one twin in each pair exhibited a history of learning difficulties was utilized to examine the etiology of inattention and hyperactivity/impulsivity (hyp/imp). Symptoms of attention-deficit/hyperactivity disorder (ADHD) were assessed by the DSM-III Diagnostic Interview for Children and Adolescents. Inattention and hyp/imp composite scores were created based on results of a factor analysis. Results indicated that extreme ADHD scores were almost entirely attributable to genetic influences across several increasingly extreme diagnostic cutoff scores. Extreme inattention scores were also highly heritable whether or not the proband exhibited extreme hyp/imp. In contrast, the heritability of extreme hyp/imp increased as a linear function of the number of inattention symptoms exhibited by the proband. This finding suggests that extreme hyp/imp may be attributable to different etiological influences in individuals with and without extreme inattention. If this result can be replicated in other samples, it would provide evidence that the hyp/imp symptoms exhibited by individuals with Combined Type ADHD and Predominantly Hyp/Imp Type ADHD may be attributable to different etiological influences. 相似文献
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Self-report measures of depression and anxiety in children are highly correlated and distinguishing between shared and independent factors in their etiologies is therefore problematic. The aim of this article was to test whether less correlated measures of depression and anxiety could be produced and, if so, what genetic and environmental factors would account for the variance in these symptoms. Second-order factor analysis of the items from two standardized self-report questionnaires of depression and anxiety collected from 395 pairs of same-sex twins aged 8 to 16 years resulted in purer dimensions of depression and anxiety. Behavioral genetic analyses confirmed the distinction between these two dimensions, and bivariate analyses revealed that the association between the two was primarily accounted for by shared genetic factors. 相似文献
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Genetic and environmental influences on the association between performance‐based self‐esteem and exhaustion: A study of the self‐worth notion of burnout 下载免费PDF全文
Pia Svedberg Lennart Hallsten Jurgita Narusyte Lennart Bodin Victoria Blom 《Scandinavian journal of psychology》2016,57(5):419-426
In the self‐worth model, burnout is considered to be a syndrome of performance‐based self‐esteem (PBSE) and experiences of exhaustion. Studies have shown that PBSE and burnout indices such as Pines’ Burnout Measure (BM) are associated. Whether these variables have overlapping etiologies has however not been studied before. Genetic and environmental components of covariation between PBSE and exhaustion measured with Pines’ BM were examined in a bivariate Cholesky model using data from 14,875 monozygotic and dizygotic Swedish twins. Fifty‐two per cent of the phenotypic correlation (r = 0.41) between PBSE and Pines’ BM was explained by genetics and 48% by environmental factors. The findings of the present study strengthen the assumption that PBSE should be considered in the burnout process as proposed by the self‐worth conception of burnout. The present results extend our understanding of the link between this contingent self‐esteem construct and exhaustion and provide additional information about the underlying mechanisms in terms of genetics and environment. This finding corroborates the assumed syndrome view on burnout, while it also suggests an altered view of how the syndrome emerges and how it can be alleviated. 相似文献
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We examine the influence of genetics on economic risk preferences by administering a measure of these preferences to monozygotic (MZ) (i.e., identical) and dizygotic (DZ) (i.e., non‐identical) twin pairs. Our analysis supports a dominant genetic effect and virtually no additive genetic effect on economic risk preferences, with the heritability of preferences estimated at 0.63. These findings suggest that over half of the variation in such preferences can be explained by genetic factors, with the remainder of the variance explained by environmental influences not shared among sibling twins. We discuss the implications of our findings for the study of individual differences in economic risk preferences. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Kylie M. Routledge Karen L. O. Burton Leanne M. Williams Anthony Harris Peter R. Schofield C. Richard Clark 《Cognition & emotion》2017,31(7):1465-1479
Alterations to cognitive function are often reported with depression and anxiety symptoms, yet few studies have examined the same associations with mental well-being. This study examined the association between mental well-being, depression and anxiety symptoms and cognitive function in 1502 healthy adult monozygotic (MZ) and dizygotic (DZ) twins, and the shared/unique contribution of genetic (G) and environmental (E) variance. Using linear mixed models, mental well-being was positively associated (p?.01) with sustained attention (β?=?0.127), inhibition (β?=?0.096), cognitive flexibility (β?=?0.149), motor coordination (β?=?0.114) and working memory (β?=?0.156), whereas depression and anxiety symptoms were associated (p?.01) with poorer sustained attention (β?=??0.134), inhibition (β?=??0.139), cognitive flexibility (β?=??0.116) and executive function (β?=??0.139). Bivariate twin modelling showed well-being shared a small environmental correlation with motor coordination and a small genetic correlation with working memory. Trivariate twin modelling showed well-being shared a small genetic correlation with inhibition, whereas depression and anxiety symptoms shared a small environmental correlation with inhibition. The remaining variance was mostly driven by unique G and/or E variance. Overall, well-being and depression and anxiety symptoms show both independent and shared relationships with cognitive functions but this is largely attributable to unique G or E variance and small shared G/E variance between pairs of variables. 相似文献
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Aggressive behaviors of 38 twin pairs (21 monozygotic [MZ], 17 dizygotic [DZ]) between the ages of 4 and 7 years were assessed through mothers' ratings and observations in their homes. An observation checklist was developed in which mothers were asked to observe and report each child's specific aggressive behaviors for a total of 6 hours spread over 3 days. In particular the observations focused on the following behaviors: rejection, destructiveness, negativism, noncompliance, teasing, physical negative, insult, verbal threat, and yelling. Biometrical genetic analysis evidenced significant heritable influences on composite aggression scores in both the observation checklist and the mothers' ratings; heritability estimates varied from.24 to.94 depending on the aggression nieasnre used, with scores from the mothers' observations demonstrating smaller genetic effect than those of the parental ratings of the environmental sources of variance, within-family factors were far more important than the between-family ones. The results also yielded significant sex and zygosity differences for means of some of the specific aggressive behaviors, where males and DZ twins scored higher than females and MZ twins. It was suggested that future studies should include more detailed investigations of the context in which specific aggressive behaviors occur and the sources toward which they are directed in order to determine the extent to which different types of aggression may have different etiologies. 相似文献
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Hilde Colpin Agnes De Munter Kristien Nys Lieve Vandemeulebroecke 《Infant and child development》1998,7(4):223-227
The present study aims at contributing to a better understanding of prenatal attachment in parents expecting twins. In particular, the relationship between prenatal attachment (measured with the Questionnaire for Antenatal Emotional Attachment) and three other psychosocial factors—the parents' psychosocial well-being and the quality of the marital relationship (respectively assessed with the General Health Questionnaire and the Relational Interactional Satisfaction Scale) and the presence of older children in the family—was investigated in both future mothers and fathers at 27 weeks of gestation. Multiple regression analysis revealed no significant relationship between the intensity of prenatal attachment and either of the three variables. For the mothers, a significant positive relationship was found between the quality of attachment on the one hand and psychosocial well-being and quality of the marital relationship on the other hand. For the fathers, the quality of attachment was only significantly predicted by the quality of the marital relationship. © 1998 John Wiley & Sons, Ltd. 相似文献
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The use of assisted reproductive technology is increasing rapidly. Research, although sparse, has resulted in inconsistent findings as to the developmental prognosis for infants conceived by assisted reproductive techniques such as in vitro fertilization and the use of fertility drugs. In the present study, the authors compared twins who were spontaneously conceived with those who were conceived through assisted reproductive technology. The authors found differences in birth weight and gestational age. Infants conceived by assisted reproductive technology fared worse than did those who were spontaneously conceived. The authors found no differences between the groups in mental development at 24 months of age, but they found evidence of differences in physical development. Implications of the findings are discussed. 相似文献
40.
Hidetoshi Somekawa Kiyomi Nakajima Alok Singh Toshiji Mukai 《Philosophical Magazine Letters》2013,93(11):831-839
The ductile fracture mechanism in a fine-grained magnesium alloy has been investigated by transmission electron microscopy-focused ion beam techniques. In coarse-grained or conventional magnesium alloys, twins form at the very beginning of the deformation process, and crack propagation occurs through the twin boundaries. However, in the alloy used in this study, subgrain structures were found instead of twins at the crack tip. Nanoscale twins formed subsequently owing to large stress in the crack propagation route. The fine-grained alloys showed high fracture toughness resulting from resistance to the twins at the beginning of the deformation. 相似文献