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101.
The current study examined the contributions of maternal and peer support to depressive symptoms in early to mid-adolescence and variation in these contributions across age, gender, and race. Five waves of data on maternal support, peer support, and depressive symptoms were collected on rural youth (N = 3,444) at 6 month intervals. Multilevel modeling was used to evaluate within and between-person effects of maternal and peer support on depressive symptoms. Within-person effects of peer support did not vary by age, gender, or race. At the between-person level, peer support predicted levels of depressive symptoms at age 12, but this effect became nonsignificant after controlling for maternal support. Within-person effects of maternal support did not vary with age but were qualified by gender and race. Between-person effects of maternal support on depressive symptom levels at age 12 and slopes varied across race and gender, respectively. Findings highlight the robustness of the protective effects of maternal and peer support during adolescence among girls and white youth.  相似文献   
102.
Fingers can be used to express numerical magnitudes, and cultural habits about the fixed order in which fingers are raised determine which configurations become canonical and which non-canonical. Although both types of configuration carry magnitude information, it has been shown that the canonical ones are recognized faster and directly linked to number semantics. Here we tested whether this difference is a consequence of differences in the qualitative way of processing the two types of configurations. When participants named Arabic digits (Experiment 1) or verbal numerals (Experiment 2) primed by canonical and non-canonical finger configurations, qualitatively different priming patterns were observed for the two types of configurations. Canonical configurations activated a place coding representation, with priming spreading to close smaller and larger magnitudes as a function of the prime–target distance. Conversely, non-canonical configurations activated a summation coding representation priming smaller and equal magnitudes independently of the prime–target distance, and larger targets depending on this distance.  相似文献   
103.

Aim

This study examined whether the predictors of self-reported aggressive driving perpetration and victimization vary across age groups.

Method

Based on data from a general-population telephone survey conducted from July 2002 through June 2005, three groups of drivers were examined: 18–34 year-olds (N = 1522), 35–54 year-olds (N = 2726), and 55 years of age or older (N = 1883). For each age group sample, logistic regression analyses examined self-reported aggressive driving perpetration and victimization in the last 12 months by measures of driving exposure, heavy drinking, cannabis use, and drinking-driving, while controlling for demographic factors.

Results

The prevalence of aggressive driving perpetration within the past year was highest for the youngest age group (51%), followed by the middle-aged group (37%), and then the oldest age group (18%). The same pattern of results was found for prevalence of aggressive driving victimization (54%, 47%, and 31%, respectively). Controlling for demographic factors, the predictors of perpetration were generally consistent across the age groups. The logistic regression model for the youngest drivers revealed that those who reported stressful driving, heavy drinking, and cannabis use had significantly increased odds of reporting perpetration of aggressive driving. For middle-aged and older drivers, stressful driving, driving on busy roads, cannabis use, and driving after drinking were associated with perpetration. In addition, increased mileage contributed to perpetration in the oldest group. The findings for victimization by aggressive driving were similar. The logistic regression model for the youngest age group identified stressful driving, cannabis use, and higher annual mileage as being associated with victimization. For the oldest age group, these same variables were significant predictors of victimization, in addition to driving on busy roads. The logistic regression for the middle-aged group identified the same predictors as that of the oldest age group; however, interestingly driving after drinking was found to predict lower victimization among middle-aged drivers.

Conclusions

Although the prevalence of aggressive driving perpetration and victimization declined with age, the factors that contributed to aggressive driving remained generally stable across the lifespan. The results suggest that efforts to reduce aggressive driving among young drivers may prove to be effective for drivers from all age groups.  相似文献   
104.
Voltage-gated potassium channels (Kv) are critically involved in learning and memory processes. It is not known, however, whether the expression of the Kv1.1 subunit, constituting Kv1 channels, can be specifically regulated in brain areas important for learning and memory processing. Radioactive in situ hybridization was used to evaluate the content of Kv1.1 α-subunit mRNA in the olfactory bulb, ventral, and dorsal hippocampus at different stages of an odor-discrimination associative task in rats. Naive, conditioned, and pseudoconditioned animals were sacrificed at different times either prior to a two-odor significance learning or after odor discrimination was established. Important decreases of Kv1.1 mRNA levels were transiently observed in the ventral hippocampus before successful learning when compared with the pseudoconditioned group. Moreover, temporal group analysis showed significant labeling alterations in the hippocampus of conditioned and pseudoconditioned groups throughout the training. Finally, Kv1.1 mRNA levels in the hippocampus were positively correlated with odor-reward association learning in rats that were beginning to discriminate between odors. These findings indicate that the Kv1.1 subunit is transiently down-regulated in the early stages of learning and suggest that Kv1 channel expression regulation is critical for the modification of neuronal substrates underlying new information acquisition.  相似文献   
105.
We conducted six experiments to examine how manipulating perception versus action affects perception–action recalibration in real and imagined blindfolded walking tasks. Participants first performed a distance estimation task (pretest) and then walked through an immersive virtual environment on a treadmill for 10 min. Participants then repeated the distance estimation task (posttest), the results of which were compared with their pretest performance. In Experiments 1a, 2a, and 3a, participants walked at a normal speed during recalibration, but the rate of visual motion was either twice as fast or half as fast as the participants' walking speed. In Experiments 1b, 2b, and 3b, the rate of visual motion was kept constant, but participants walked at either a faster or a slower speed. During pre- and posttest, we used either a blindfolded walking distance estimation task or an imagined walking distance estimation task. Additionally, participants performed the pretest and posttest distance estimation tasks in either the real environment or the virtual environment. With blindfolded walking as the distance estimation task for pre- and posttest, we found a recalibration effect when either the rate of visual motion or the walking speed was manipulated during the recalibration phase. With imagined walking as the distance estimation task, we found a recalibration effect when the rate of visual motion was manipulated, but not when the walking speed was manipulated in both the real environment and the virtual environment. Discussion focuses on how spatial-updating processes operate on perception and action and on representation and action.  相似文献   
106.
Online social networking is vastly popular and permits its members to post their thoughts as microblogs, an opportunity that people exploit, on Facebook alone, over 30 million times an hour. Such trivial ephemera, one might think, should vanish quickly from memory; conversely, they may comprise the sort of information that our memories are tuned to recognize, if that which we readily generate, we also readily store. In the first two experiments, participants’ memory for Facebook posts was found to be strikingly stronger than their memory for human faces or sentences from books—a magnitude comparable to the difference in memory strength between amnesics and healthy controls. The second experiment suggested that this difference is not due to Facebook posts spontaneously generating social elaboration, because memory for posts is enhanced as much by adding social elaboration as is memory for book sentences. Our final experiment, using headlines, sentences, and reader comments from articles, suggested that the remarkable memory for microblogs is also not due to their completeness or simply their topic, but may be a more general phenomenon of their being the largely spontaneous and natural emanations of the human mind.  相似文献   
107.
Differences between languages in terms of number naming systems may lead to performance differences in number processing. The current study focused on differences concerning the order of decades and units in two-digit number words (i.e., unit-decade order in German but decade-unit order in French) and how they affect number magnitude judgments. Participants performed basic numerical tasks, namely two-digit number magnitude judgments, and we used the compatibility effect (Nuerk et al. in Cognition 82(1):B25–B33, 2001) as a hallmark of language influence on numbers. In the first part we aimed to understand the influence of language on compatibility effects in adults coming from German or French monolingual and German–French bilingual groups (Experiment 1). The second part examined how this language influence develops at different stages of language acquisition in individuals with increasing bilingual proficiency (Experiment 2). Language systematically influenced magnitude judgments such that: (a) The spoken language(s) modulated magnitude judgments presented as Arabic digits, and (b) bilinguals’ progressive language mastery impacted magnitude judgments presented as number words. Taken together, the current results suggest that the order of decades and units in verbal numbers may qualitatively influence magnitude judgments in bilinguals and monolinguals, providing new insights into how number processing can be influenced by language(s).  相似文献   
108.
In a sample of 351 young adults, the authors assessed whether borderline personality disorder (BPD) features prospectively predicted negative outcomes (poorer academic achievement and social maladjustment) over the subsequent 2 years, over and above gender and both Axis I and Axis II psychopathology. Borderline traits were significantly related to these outcomes, with impulsivity and affective instability the most highly associated. The present findings suggest that the impulsivity and affective instability associated with BPD leads to impairment in relating well with others, in meeting social role obligations, and in academic or occupational achievement. Therefore, these may be especially important features to target in interventions for BPD.  相似文献   
109.
Spoken word recognition involves brief activation of candidate words. Six experiments examined whether words semantically related to phonologically activated words would be falsely recognized. Experiments 1 and 2 involved homophones as test words; Experiment 3 used strong associates for the semantic mediation link. Experiment 4 approximated lists of "strong" converging associates. Experiment 5 expanded the real time needed for word identification by using a gating procedure during study. In Experiment 6, the goal was to create a more sensitive test by requiring participants to indicate which of two lures (mediated or control) was "most likely" to be new. Recognition errors were sensitive to separate phonetic and semantic stages in the mediated chain; however, there was little evidence of mediated false recognition, despite expectations derived from common models of spreading activation.  相似文献   
110.
This paper examines the relationship between workaholism, sex, and sex role orientation among professionals. The sample consisted of 86 male and 106 female attorneys, physicians, and psychologists/therapists. Results indicated a significant relationship between sex and sex role stereotyping. Among females, workaholics were grouped exclusively in the sex role categories masculine and androgynous. Implications for counseling include increasing awareness of changing sex role attitudes among professional women and possible role conflict that can occur from integration of work and family.  相似文献   
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