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41.
Seals D  Young J 《Adolescence》2003,38(152):735-747
This study investigated the prevalence of bullying and victimization among students in grades 7 and 8. It also explored the relationship of bullying and victimization to gender, grade level, ethnicity, self-esteem, and depression. Three survey instruments were used to obtain data from a convenience sample of 454 public school students. Twenty-four percent reported bullying involvement. Chi-square tests indicated significantly more male than female bullying involvement, seventh graders reported more involvement than did eighth graders, and there were no statistically significant differences in involvement based on ethnicity. Both bullies and victims manifested higher levels of depression than did students who were neither bullies nor victims. There were no significant differences between groups in terms of self-esteem.  相似文献   
42.
The construct validity of the Eating Disorder Inventory (EDI) was examined in 3 samples. An archival clinic sample (n = 318) of women completed the EDI, a structured interview, and the Millon Clinical Multiaxial Inventory-II (MCMI-II). Confirmatory factor analyses (CFAs) indicated that neither null nor 1-factor models of the EDI fit item-level or item-parcel data. The proposed 8-factor model did not fit at the item level but did fit item-parcel data. Reliability estimates of the 8 scales ranged from .82 to .93, and low-to-moderate interscale correlations among the eating and weight-related scales provided partial support for convergent validity. EDI personality scales showed moderate interscale correlations and were associated with MCMI-II scales. A final CFA of the EDI scales supported a 2-factor model (Eating and Weight, Personality) of the 8 EDI scales. Strong associations between depression and several EDI scale scores were found in a treatment study sample (n = 50). The archival clinic sample scored significantly higher on the 8 EDI scales than the nonpatient college comparison sample (n = 487).  相似文献   
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The speeded categorisation of gender from photographs of men's and women's faces under conditions of vertical brow and vertical head movement was explored in two sets of experiments. These studies were guided by the suggestion that a simple cue to gender in faces, the vertical distance between the eyelid and brow, could support such decisions. In men this distance is smaller than in women, and can be further reduced by lowering the brows and also by lowering the head and raising the eyes to camera. How does the gender-classification mechanism take changes in pose into account? Male faces with lowered brows (experiment 1) were more quickly and accurately categorised (there was little corresponding 'feminisation' of raised-brow faces). Lowering gaze had a similar effect, but failed to interact with head lowering in a simple manner (experiment 2). We conclude that the initial classification of gender from the facial image may not involve normalisation of the face image to a canonical state (the 'mug-shot view') for expressive pose (brow movement and direction of gaze). For head pose (relative position of the features when the face is not viewed head-on), normalisation cannot be ruled out. Some perceptual mechanisms for these effects, and their functional implications, are discussed.  相似文献   
46.
Attention and social functioning and their interrelationships have not been routinely examined in children with early brain insult (EBI). This study aimed to describe attention and social functioning in children with two types of EBI: malformations of cortical development (MCD) and stroke. Children diagnosed with MCD (n = 14, 6 males) or stroke (n = 14, 8 males) aged 8 to 14 years (M = 12 years 11 months) completed neuropsychological assessments to examine attention processes. Primary caregivers completed a questionnaire to assess executive components of children's attention and teachers completed a questionnaire to measure children's social functioning. Brain scans (MRI or CT) were coded by a pediatric neuroradiologist. Higher rates of impairments in attention and social function were found in children with EBI compared with normative expectations. Children with MCD experienced more global and clinically significant levels of impairment than children with stroke; though impairments were present in both groups. A strong association between executive components of attention and social function was observed. In addition, complex attention processes were associated with social function. The findings emphasize the reciprocity between attention, behavior and social outcomes, and the vulnerability of social function following EBI.  相似文献   
47.
Mounting evidence has established that diet-induced obesity (DIO) is associated with deficits in hippocampus-dependent memory. The bulk of research studies dealing with this topic have utilized rats fed a high-fat diet as an experimental model. To date, there has been a paucity of research studies that have established whether the memory deficits exhibited in DIO rats can be recapitulated in mice. Moreover, the majority of experiments that have evaluated memory performance in rodent models of DIO have utilized memory tests that are essentially aversive in nature (i.e., Morris water maze). The current study sought to fill an empirical void by determining if mice maintained on a high-fat diet exhibit deficits in two non-aversive memory paradigms: novel object recognition (NOR) and object location memory (OLM). Here we report that mice fed a high-fat diet over 23 weeks exhibit intact NOR, albeit a marked impairment in hippocampus-dependent OLM. We also determined the existence of corresponding aberrations in gene expression within the hippocampus of DIO mice. DIO mice exhibited significant reductions in both SIRT1 and PP1 mRNA within the hippocampus. Our data suggest that mice maintained on a high-fat diet present with impaired hippocampus-dependent spatial memory and a corresponding alteration in the expression of genes that have been implicated in memory consolidation.  相似文献   
48.
According to the rapid auditory processing theory, the ability to parse incoming auditory information underpins learning of oral and written language. There is wide variation in this low-level perceptual ability, which appears to follow a protracted developmental course. We studied the development of rapid auditory processing using event-related potentials (ERPs) elicited by tone pairs presented at varying inter-stimulus intervals (25, 50, 100, 200, and 400 ms) in a sample of children (N = 103) aged 7-9 years initially and again at 9-11 years. We also assessed their ability to repeat nonsense words at both time-points. The amount of difference between the ERP to single tones and paired tones (as assessed by the intra-class correlation coefficient, ICC) provided a measure of the brain's capacity to discriminate auditory information delivered at different presentation rates. Results showed that older children showed greater neural discrimination to tone pairs than younger children at rapid presentation rates, although these differences were reduced at slower presentation rates. The ICC at time 1 significantly predicted nonword repetition scores two years later, providing support for the view that rapid auditory temporal processing ability affects oral language development in typically developing children.  相似文献   
49.
The relation between temperament and happiness was assessed in a sample of 441 children aged 7–14 years drawn from a population in Northern India. Parents assessed their children’s happiness and rated their children’s temperament using the Emotionality, Activity, and Sociability Temperament Survey (EAS). Children self-reported their own happiness using a single-item measure, the Oxford Happiness Scale Short Form, and the Subjective Happiness Scale. Parents’ temperament ratings conformed to the four factor structure proposed by Buss and Plomin (Temperament: early developing personality traits. Lawrence Erlbaum Associates, Hillsdale, 1984): Emotionality, Activity, Sociability, and Shyness. Temperament accounted for between 4 and 11% of the variance in children’s happiness depending on the measures. Children who were more social and active, and less shy, were happier. This result parallels the well-established relation between happiness and personality in adults and is similar to recent research on happiness and temperament in children; temperament traits akin to extraversion were positively associated with happiness. However, despite that neuroticism and its temperament counterpart are strongly and consistently linked to happiness in adults, the relation between happiness and the temperament trait associated with neuroticism (i.e., Emotionality) was weak. This suggests that the relations between temperament and happiness in children may not completely generalize across cultures.  相似文献   
50.
Contemporary optimization models suggest that animals optimize benefits of foraging and minimize its costs. For wild bearded capuchins (Sapajus libidinosus), nut-cracking entails cost related to lifting the heavy stone and striking the nut and additional cost to transport the stone if it is not already on the anvil. To assess the role of stone mass and transport distance in capuchins’ tool selection, we carried out three field experiments. In Experiment 1, we investigated whether transport distance affected choice of a tool by positioning two stones of the same mass close and far from the anvil. Capuchins consistently selected the closer stone, effectively reducing transport costs. In Experiment 2, we examined the trade-off between the cost of transport and the effectiveness in cracking by positioning two stones of different mass close and far from the anvil. Most subjects significantly preferred the closer stone, regardless of mass, whereas others preferred the heavier stone regardless of transport distance. In Experiment 3, we changed transport distance of both stones while maintaining the same distance ratios as in Experiment 2. Capuchins maintained the preferences expressed in Experiment 2, with the exception of one subject. Overall, our findings indicate that (1) individuals vary in their sensitivity to distance of transport, (2) a few meters are perceived as a substantive cost by some monkeys, and (3) monkeys’ body mass affects their decisions. We also developed a non-dimensional Preference index (P) defined as a function of the stone mass and the transport distance to describe monkey’s choice.  相似文献   
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