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901.
902.
Brain imaging studies have identified two cortical areas, the parahippocampal place area (PPA) and the retrosplenial complex (RSC), that respond preferentially to the viewing of scenes. Contrary to the PPA, little is known about the functional maturation and cognitive control of the RSC. Here we used functional magnetic resonance imaging and tasks that required attention to scene (or face) images and suppression of face (or scene) images, respectively, to investigate task-dependent modulation of activity in the RSC and whole-brain functional connectivity (FC) of this area in 7–11-year-old children and young adults. We compared responsiveness of the RSC with that of the PPA. The RSC was selectively activated by scene images in both groups, albeit less than the PPA. Children modulated activity between the tasks similarly in the RSC and PPA, and to the same extent as adults in PPA, whereas adults modulated activity in the RSC less than in PPA. In children, the whole brain FC of the RSC was stronger in the Sf than Fs task between the left RSC and right fusiform gyrus. The between groups comparison suggested stronger FC in children than adults in the Sf task between the right RSC and the left inferior parietal lobule and intraparietal sulcus. Together the results suggest that the function of the RSC and the related networks undergo dynamic changes over the development from 7–11-year-old children to adulthood.  相似文献   
903.
The purpose of the present study is to analyze how the Slow Wave develops in the retention period on a visual Delayed Match-to-Sample task performed by 170 subjects between 6 and 26 years old, divided into 5 age groups. In addition, a neuropsychological test (Working Memory Test Battery for Children) was correlated with this Event Related Potential (ERP) in order to observe possible relationships between Slow Wave maturation and the components of Baddeley and Hitch’s Working Memory model.The results showed a slow negativity during the retention period in the posterior region in all the age groups, possibly resulting from sustained neural activity related to the visual item presented. In the anterior region, a positive slow wave was observed in the youngest subjects. Dipole analysis suggests that this fronto-central positivity in children (6–13 years old) consists of the positive side of the posterior negativity, once these subjects only needed two posterior dipoles to explain almost all the neural activity. Negative correlations were shown between the Slow Wave and the Working Memory Test Battery for Children, indicating a commonality in assessing Working Memory with the Slow Wave and the neuropsychological testing.  相似文献   
904.
While healthy aging is associated with physiological changes that can impair control of trunk motion, few studies examine how spinal muscle responses change with increasing age. This study examined whether older (over 65 years) compared to younger (20–45 years) adults had higher overall amplitude and altered temporal recruitment patterns of trunk musculature when performing a functional transfer task. Surface electromyograms from twelve bilateral trunk muscle (24) sites were analyzed using principal component analysis, extracting amplitude and temporal features (PCs) from electromyographic waveforms. Two PCs explained 96% of the waveform variance. Three factor ANOVA models tested main effects (group, muscle and reach) and interactions for PC scores. Significant (p < .0125) group interactions were found for all PC scores. Post hoc analysis revealed that relative to younger adults, older adults recruited higher agonist and antagonistic activity, demonstrated continuous activation levels in specific muscle sites despite changing external moments, and had altered temporal synergies within abdominal and back musculature. In summary both older and younger adults recruit highly organized activation patterns in response to changing external moments. Differences in temporal trunk musculature recruitment patterns suggest that older adults experience different dynamic spinal stiffness and loading compared to younger adults during a functional lifting task.  相似文献   
905.
Freezing of gait (FOG) in Parkinson’s disease (PD) is typically assumed to be a pure motor deficit, although it is important to consider how an abrupt loss of gait automaticity might be associated with an overloaded central resource capacity. If resource capacity limits are a factor underlying FOG, then obstacle crossing may be particularly sensitive to dual task effects in eliciting FOG. Participants performed a dual task (auditory digit monitoring) in order to increase cognitive load during obstacle crossing. Forty-two non-demented participants (14 PD patients with FOG, 13 PD who do not freeze, and 14 age-matched healthy control participants) were required to walk and step over a horizontal obstacle set at 15% of the participants’ height. Kinematic data were split into two phases of their approach: early (farthest away from the obstacle), and late (just prior to the obstacle). Interestingly, step length variability and step time variability increased when PD patients with FOG performed the dual task, but only in the late phase prior to the obstacle (i.e. when closest to the obstacle). Additionally, immediately after crossing, freezers landed the lead foot abnormally close to the obstacle regardless of dual task condition, and also contacted the obstacle more frequently (planning errors). Strength of the dual task effect was associated with low general cognitive status, declined executive function, and inappropriate spatial planning, but only in the PD-FOG group. This study is the first to demonstrate that cognitive load differentially impacts planning of the final steps needed to avoid an obstacle in PD patients with freezing, but not non-freezers or healthy controls, suggesting specific neural networks associated with FOG behaviours.  相似文献   
906.
907.
908.
Omission bias occurs when people are more reluctant to accept negative consequences caused by their actions than by their inaction. Recent research on omission bias in decision‐making has found evidence for individual differences, thus indicating that some people are more likely to show omission inclination than others. The present research aims to explore the role of regulatory focus as individual difference variables in omission bias. Moreover, we examine whether anticipated regret mediates the relationship between regulatory focus and moral judgement. Moral judgement tasks utilized include: (i) moral dilemma scenarios (Study 1); and (ii) ethical scenarios embracing apparent legal rule violations (Study 2). The results of both studies show that only prevention focus is significantly related to omission bias in moral judgement. Specifically, this relationship holds regardless of the nature of the ‘omission’ (whether they are deontological or utilitarian). In addition, anticipated regret/guilt for action was found to mediate the relationship between prevention focus and omission bias. Implications and limitations are discussed based on the results of the current study.  相似文献   
909.
为了探索不同方位辨别方式的男女差异,采用自编的经过心理测量学检测符合指标的空间知觉量表和三个语言线索下方位辨别任务范式实验,在测验和实验3中设计两种空间知觉加工方式,即东西南北和前后左右;在实验1中设计东西南北;在实验2中设计前后左右。测验,实验1和实验3均发现,在东西南北方位辨别上存在显著的性别差异,且男生优于女生;测验,实验2和实验3均发现,在前后左右方位辨别上不存在显著的性别差异。这表明男生更擅长于使用东西南北的方位辨别方式。  相似文献   
910.
《Body image》2014,11(1):1-10
A negative body image has been associated with a variety of negative health and well-being outcomes. Social pressures from others, in the form of weight-related social control, may serve to exacerbate this effect, especially for college-aged women. Undergraduate students (N = 399) completed a variety of questionnaires assessing weight-related social control, well-being, and diet and exercise behaviors. The results suggest that weight is associated with a variety of negative health and well-being outcomes and particularly for women, weight-related social control is also associated with these negative effects. In addition, men of higher body mass indexes (BMIs) or higher self-perceived weight did not experience negative health and well-being outcomes to the same degree that overweight women did. Parents in particular seem to instigate weight-related social control to change students’ diet and exercise behaviors. These results help clarify the effects of weight-related social control in a college population, where weight may be especially important.  相似文献   
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