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961.
Maternal smoking and depressive symptoms are independently linked to poor child health outcomes. However, little is known about factors that may predict maternal depressive symptoms among low-income, African American maternal smokers—an understudied population with children known to have increased morbidity and mortality risks. The objective of this study was to test the hypothesis that secondhand smoke exposure (SHSe)-related pediatric sick visits are associated with significant maternal depressive symptoms among low-income, African American maternal smokers in the context of other depression-related factors. Prior to randomization in a behavioral counseling trial to reduce child SHSe, 307 maternal smokers in Philadelphia completed the Center for Epidemiologic Studies Depression (CES-D) and questionnaires measuring stressful events, nicotine dependence, social support, child health and demographics. CES-D was dichotomized at the clinical cutoff to differentiate mothers with significant versus low depressive symptoms. Results from direct entry logistic regression demonstrated that maternal smokers reporting more than one SHSe-related sick visit (OR 1.38, p < .001), greater perceived life stress (OR 1.05, p < .001) and less social support (OR 0.82, p < .001) within the last 3 months were more likely to report significant depressive symptoms than mothers with fewer clinic visits, less stress, and greater social support. These results suggest opportunities for future hypothesis-driven evaluation, and exploration of intervention strategies in pediatric primary care. Maternal depression, smoking and child illness may present as a reciprocally-determined phenomenon that points to the potential utility of treating one chronic maternal condition to facilitate change in the other chronic condition, regardless of which primary presenting problem is addressed. Future longitudinal research could attempt to confirm this hypothesis.  相似文献   
962.
Abstract

Sixty male Vietnam combat veterans, 30 hospitalized for post-traumatic stress disorder (PTSD) and 30 with no PTSD or other psychiatric disorder, sorted and labeled their life events into numeric matrices (repertory grids). Through hierarchical-classes analysis of a subject's matrix, we could compare the hierarchical level (elaboration) of the subject's constructs of a negative combat event with the hierarchical levels of other subjects' constructs of negative combat events and with the subject's precombat life event construction. As predicted, the level of construct elaboration was virtually identical for the two groups for precombat non-trauma-related events but was reduced in the PTSD group for the negative combat event. In addition, the Pythagorean distance scores of the PTSD group indicated less conceptual distance between the negative combat event and negative life events after Vietnam compared with the non-PTSD group's scores. Patients with PTSD rated negative life events more extremely (fewer “shades of gray” ratings) than did the non-PTSD group, especially life events that occurred after Vietnam.  相似文献   
963.
964.
Single-word naming is one of the most widely used experimental paradigms for studying how we read words. Following the seminal study by Spieler and Balota (Psychological Science 8:411–416, 1997), accounting for variance in item-level naming databases has become a major challenge for computational models of word reading. Using a new large-scale database of naming responses, we first provided a precise estimate of the amount of reproducible variance that models should try to account for with such databases. Second, by using an item-level measure of delayed naming, we showed that it captures not only the variance usually explained by onset phonetic properties, but also an additional part of the variance related to output processes. Finally, by comparing the item means from this new database with the ones reported in a previous study, we found that the two sets of item response times were highly reliable (r = .94) when the variance related to onset phonetic properties and voice-key sensitivity was factored out. Overall, the present results provide new guidelines for testing computational models of word naming with item-level databases.  相似文献   
965.
Visual working memory performance often declines when objects are tested in new positions from those they were observed. We report an asymmetry in repositioning costs for orientation compared to colour memory (Experiment 1). Follow-up experiments demonstrated a similar asymmetry for line length memory compared to shape memory (Experiment 2). When different shades of the same colour category were used, however, repositioning costs emerged for colour as well (Experiment 3). Finally, a direct comparison experiment demonstrated an asymmetry for orientation compared to categorical colours, but in a task with no explicit memory demands (Experiment 4). These results challenge previous accounts of repositioning costs, suggesting that they emerge not due to the contents of visual working memory, but naturally because of correspondence procedures that must be executed in order to use a memory to judge the present.  相似文献   
966.
ABSTRACT

Music has been shown to entrain movement. One of the body’s most frequent movements, saccades, are arguably subject to a timer that may also be susceptible to musical entrainment. We developed a continuous and highly-controlled visual search task and varied the timing of the search target presentation, it was either gaze-contingent, tap-contingent, or visually-timed. We found: (1) explicit control of saccadic timing is limited to gross duration variations and imprecisely synchronized; (2) saccadic timing does not implicitly entrain to musical beats, even when closely aligned in phase; (3) eye movements predict visual onsets produced by motor-movements (finger-taps) and externally-timed sequences, beginning fixation prior to visual onset; (4) eye movement timing can be rhythmic, synchronizing to both motor-produced and externally timed visual sequences; each unaffected by musical beats. These results provide evidence that saccadic timing is sensitive to the temporal demands of visual tasks and impervious to influence from musical beats.  相似文献   
967.
In both children and adults there is large variability in reading skill, with approximately 5–10% of individuals characterized as having reading disability; these individuals struggle to learn to read despite adequate intelligence and opportunity. Although it is well established that a substantial portion of this variability is attributed to the genetic differences between individuals, specifics of the connections between reading and the genome are not understood. This article presents data that suggest that variation in the COMT gene, which has previously been associated with variation in higher‐order cognition, is associated with reading and reading‐related skills, at the level of both brain and behavior. In particular, we found that the COMT Val/Met polymorphism at rs4680, which results in the substitution of the ancestral Valine (Val) by Methionine (Met), was associated with better performance on a number of critical reading measures and with patterns of functional neural activation that have been linked to better readers. We argue that this polymorphism, known for its broad effects on cognition, may modulate (likely through frontal lobe function) reading skill.  相似文献   
968.
969.
An experiment is reported in which young and older adults heard short English sentences that differed in syntactic complexity and speech rate. The syntactic contrast pitted center-embedded sentences with a subject-relative clause against sentences with center-embedded object-relative clauses. Speech rate was varied using computer time-compression of the speech signal. Both young and older adults showed poorer comprehension accuracy for the more complex object-relative clause sentences than subject-relative sentences, with an age difference appearing only when sentences were presented at a very rapid rate. By contrast to accuracy scores, older adults took longer than the young adults to give their comprehension responses at all speech rates tested, with this age difference amplified by both speech rate and syntactic complexity.  相似文献   
970.
Since the 1950s, there has been a systemic development of research on creative personality. Three themes are apparent in this literature: individual differences of creative people, the construct of creative personality, and longitudinal studies about creative personality. However, little research has been conducted in any of these areas with Chinese samples, and the purpose of this study is to study the construct of Chinese adolescents' creative personality. Confirmatory factor analyses were conducted with data from 1,300 Chinese adolescents. The results provide evidence that adolescents' creative personality consists of three largely independent dimensions: Internal, External, and Self. The internal factor includes self-confidence, norm-doubt, internal motivation, and persistence; the external factor includes curiosity, risk-taking, openness and independence; the self factor pertains to self-acceptance.  相似文献   
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