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691.
Background: Early symptoms of attention deficit/hyperactivity disorder (ADHD) and oppositional-defiant disorder (ODD) are associated with deficits in cognitive self-regulatory processes or executive functions (EF)s. However, the hypothesis that neurocognitive deficits underlying the two disorders are already evident during early preschool years still has limited empirical support. The present study investigated associations between symptoms of ADHD and/or ODD and two core EFs, inhibition and working memory, in a large nonclinical sample of 3-year old children. Method: Participants were 1045 children (554 boys, age 37–47 months), recruited from the population based Norwegian Mother and Child Cohort Study (MoBa). Relations between behavioral symptoms and measures of inhibition and working memory were studied both categorically and dimensionally. Results: Children with co-occurring symptoms of ADHD and ODD performed at a significantly lower level than typically developing children in 4 out of 5 EF measures. Symptoms of ADHD, both alone and in combination with ODD, were associated with reduced performance on tests of inhibition in the group comparisons. Dimensional analyses showed that performance within both EF domains contributed to variance primarily in ADHD symptom load. The associations between test results and behavioral symptoms remained significant after gender and verbal skills had been controlled. Conclusion: Young preschoolers show the same pattern of relations between EF and behavioral symptoms of ADHD and/or ODD as previously described in older children diagnosed with ADHD and/or ODD. Effect sizes were generally small, indicating that measures of EF have limited clinical utility at this stage in development.  相似文献   
692.
B Lust  Y C Chien 《Cognition》1984,17(1):49-83
This study exemplifies a type of cross-linguistic research which is based on the theory that certain parameters of natural language variation are central to the human competence for language. Sensitivity to these parameters allows the child to develop various specific language structures which follow from setting the parameters. Results of this study provide evidence that children are universally sensitive to one such parameter, namely, Principal Branching Direction.Data are based on results of a standardized elicited imitation test of 68 Chinese children in Taiwan between 2;0 and 4;5 with mean age of 3;3. The test is on a set of coordinate sentences. The results show that children acquiring Mandarin Chinese (a left-branching language) systematically prefer VO sentences with a backward reduction pattern ([V + V]O) over those with a forward reduction pattern (V[O + O]).Children's responses to SV coordinate sentences differ systematically from their VO responses. They very frequently reduce redundant subjects in a forward direction (in SV sentences) and do not prefer backward reduction ([S + S])V) over forward reduction (S[V + V]) in these SV sentences.This paper suggests an explanation of this apparent paradox in terms of an interaction in early language acquisition between children's sensitivity to a predominant Chinese topic-comment structure (in SV) and their sensitivity to the abstract, specifically grammatical concept of “Principal Branching Direction”.  相似文献   
693.
694.
Visual attention plays a key role in infants’ interaction with the environment, and shapes their behavioral and brain development. As such, early problems with flexibly switching gaze from one stimulus to another (visual disengagement) have been hypothesized to lead to developmental difficulties (e.g. joint attention and social skills) over time. This study aimed to identify cross-sectional associations between performance in the Gap task (gaze shift latencies and visual attention disengagement) and measures of development and adaptive behavior in conjunction to any sex or socioeconomic status effects in infancy. We measured visual attention disengagement in 436 5-month-old infants and calculated its association with cognitive developmental level, adaptive behaviours, socioeconomic status (SES) and biological sex. In the Gap task, participants must redirect their gaze from a central stimulus to an appearing peripheral stimulus. The three experimental conditions of the task (Gap, Baseline and Overlap) differ on the timepoint when the central stimuli disappears in relation to the appearance of the peripheral stimulus: 200 ms before the peripheral stimulus appears (Gap), simultaneously to its appearance (Baseline), or with peripheral stimulus offset (Overlap). The data from the experimental conditions showed the expected pattern, with average latencies being the shortest in the Gap and longest in the Overlap condition. Females were faster (p = .004) than males in the Gap condition, which could indicate that arousal-related effects differ as a function of biological sex. Infants from higher SES were slower (p = .031) in the Overlap condition compared to lower SES infants. This suggests that basic visual attention may differ by socio-cultural background, and should be considered when studying visual attention and its developmental correlates. We observed no significant association to concurrent developmental level or adaptive function. Given its large sample size, this study provides a useful reference for future studies of visual disengagement in early infancy.  相似文献   
695.
This study examined whether others (i.e., teachers and parents) and self-appraisals of social competence mediated the relationship between Attention-Deficit/Hyperactivity Disorder (ADHD) and depression. To determine whether age moderated the effects of the mediation, the total sample was divided into younger (under 9) and older (at or above 9 years) age levels. The total sample (age range 6.6 to 11.7 years) was primarily male (194 boys and 52 females) and consisted of 148 children diagnosed with ADHD and 98 community controls. Three central findings were derived from this study. First, there was a strong relationship between ADHD (with and without comorbid ODD/CD) and depression in both younger and older aged children. Among younger children with ADHD, there was no differential influence on the level of depression depending on whether or not ADHD was comorbid with ODD/CD; in contrast, with older children, comorbid ODD/CD had higher levels of depression than was the case for children with ADHD that did not display such comorbidity. Second, with younger children approximately half of the relationship between ADHD (with and without comorbid ODD/CD) and depression was exclusively mediated by others appraisal of social competence. Third, a more complex relationship between ADHD and depression emerged during the later part of the childhood years. As such, the relationship between ADHD, others appraisals of social competence, and depression was further mediated by self-appraisals of social competence. Findings are discussed in terms of developmental theory and theoretical models of childhood depression.Rick Ostrander and David S. Crystal contributed equally to this article, and the order of authorship was determined by a coin toss.  相似文献   
696.
In an academic setting, we tested competing predictions derived from two conceptual models about the effects of approach and avoidance referents (e.g., goals and role models) on student performance. One model suggests a main effect such that focusing on approach referents leads to better outcomes than focusing on avoidance referents, regardless of personality (e.g., A. J. Elliot & K. M. Sheldon, 1997). Another model suggests an interaction such that focusing on either approach or avoidance referents can lead to positive outcomes, but only when people are promotion focused or prevention focused, respectively (e.g., P. Lockwood, C. H. Jordan, & Z. Kunda, 2002). Findings supported the main effect model. The more prevention focused participants were, the more avoidance goals they generated, which led to poorer grades.
Alexander J. RothmanEmail:
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697.
Concern about the commercialization of research is rising, notably in testing new drugs. The problem involves oversimplified, polarizing assumptions about research and development (R&;D) and intellectual property (IP). To address this problem this paper sets forth a more complex three phase RT&;D process, involving Scientific Research (R), Technological Innovation (T), and Commercial Product Development (D) or the RT&;D process. Scientific research and innovation testing involve costly intellectual work and do not produce free goods, but rather require IP regulation. RT&;D processes involve an unrecognized IP shift from a common IP right in public goods like information and knowledge to private IP in products and other hard assets. The question then is, what kind of IP right: private or common? Since scientific research and innovation testing require openness about adverse findings, and wide, low cost diffusion of results, they require a common, inclusive IP right. Common IP is appropriate to both sharing knowledge goods and recovering the cost of production. Research is furthermore compatible with commercialization and support by other social interests. On the other hand it is incompatible with the exclusionary private IP rights that permit restrictive publication or total suppression of information. Private IP rather than commercialization conflicts with the openness requirements of scientific research and innovation testing. Commercial funding, however, is in principle compatible with research and testing, especially when regulated by a common IP right. This reflects a pragmatic view of the fundamental interconnections of knowledge and other social interests.  相似文献   
698.
Pitch perception is fundamental to melody in music and prosody in speech. Unlike many animals, the vast majority of human adults store melodic information primarily in terms of relative not absolute pitch, and readily recognize a melody whether rendered in a high or a low pitch range. We show that at 6 months infants are also primarily relative pitch processors. Infants familiarized with a melody for 7 days preferred, on the eighth day, to listen to a novel melody in comparison to the familiarized one, regardless of whether the melodies at test were presented at the same pitch as during familiarization or transposed up or down by a perfect fifth (7/12th of an octave) or a tritone (1/2 octave). On the other hand, infants showed no preference for a transposed over original-pitch version of the familiarized melody, indicating that either they did not remember the absolute pitch, or it was not as salient to them as the relative pitch.  相似文献   
699.
We examined the relations among phonological awareness, music perception skills, and early reading skills in a population of 100 4- and 5-year-old children. Music skills were found to correlate significantly with both phonological awareness and reading development. Regression analyses indicated that music perception skills contributed unique variance in predicting reading ability, even when variance due to phonological awareness and other cognitive abilities (math, digit span, and vocabulary) had been accounted for. Thus, music perception appears to tap auditory mechanisms related to reading that only partially overlap with those related to phonological awareness, suggesting that both linguistic and nonlinguistic general auditory mechanisms are involved in reading.  相似文献   
700.
This study examines the motivations for and the outcomes of mid-life career change among a sample of 73 men who had left professional and managerial careers between the ages of 34 and 54. Measures of personal desire for change and external pressure to leave were dichotomized to produce a typology of career changers: Drift-outs, Opt-outs, Force-outs, and Bow-outs. The four types of changers were found to differ on a number of variables, including: amount of education completed, additional schooling undertaken to change careers, time taken to make the change, radicalness of change, and the importance of personal values in deciding to leave their former careers. Overall, respondents were found to be highly satisfied with their career redirection.  相似文献   
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