Neuronal effects of auditory distraction on visual attention

Selective attention in the presence of distraction is a key aspect of healthy cognition. The underlying neurobiological processes, have not, however, been functionally well characterized. In the present study, we used functional magnetic resonance imaging to determine how ecologically relevant distracting noise affects cortical activity in 27 healthy adults during two versions of the visual Sustained Attention To Response Task (SART) that differ in difficulty (and thus attentional load). A significant condition (noise or silence) by task (easy or difficult) interaction was observed in several areas, including dorsolateral prefrontal cortex (DLPFC), fusiform gyrus (FG), posterior cingulate (PCC), and pre-supplementary motor area (PreSMA). Post hoc analyses of interaction effects revealed deactivation of DLPFC, PCC, and PreSMA during distracting noise under conditions of low attentional load, and activation of FG and PCC during distracting noise under conditions of high attentional load. These results suggest that distracting noise may help alert subjects to task goals and reduce demands on cortical resources during tasks of low difficulty and attentional load. Under conditions of higher load, however, additional cognitive resources may be required in the presence of noise.     

Temporal and spatial integration of face,object, and scene features in occipito-temporal cortex

In three neuroimaging experiments, face, novel object, and building stimuli were compared under conditions of restricted (aperture) viewing and normal (whole) viewing. Aperture viewing restricted the view to a single face/object feature at a time, with the subjects able to move the aperture continuously though time to reveal different features. An analysis of the proportion of time spent viewing different features showed stereotypical exploration patterns for face, object, and building stimuli, and suggested that subjects constrained their viewing to the features most relevant for recognition. Aperture viewing showed much longer response times than whole viewing, due to sequential exploration of the relevant isolated features. An analysis of BOLD activation revealed face-selective activation with both whole viewing and aperture viewing in the left and right fusiform face areas (FFA). Aperture viewing showed strong and sustained activation throughout exploration, suggesting that aperture viewing recruited similar processes as whole viewing, but for a longer time period. Face-selective recruitment of the FFA with aperture viewing suggests that the FFA is involved in the integration of isolated features for the purpose of recognition.     

论卫生领域中的政府角色与社会政策

从政府组织存在基本命题、社会政策变革趋势入手,深入探讨卫生领域内政府认知、政府角色、卫生政策现状及发展客观要求,提出新时期公共服务型政府能否制定并执行理性卫生政策,对管理伦理、管理机制和管理意识三方面的必要调整是关键。     

Functions of parahippocampal place area and retrosplenial cortex in real-world scene analysis: An fMRI study

We used functional MRI to investigate several hypotheses concerning the functions of posterior parahippocampal cortex and retrosplenial cortex, two regions that preferentially activate to images of real-world scenes compared to images of other meaningful visual stimuli such as objects and faces. We compared activation resulting from photographs of rooms, city streets, cityscapes, and landscapes against activation to a control condition of objects. Activation in posterior parahippocampal cortex, including parahippocampal place area, was greater for all scene types than objects, and greater for scenes that clearly convey information about local three-dimensional (3-D) structure (city streets and rooms) than scenes that do not (cityscapes and landscapes). Similar differences were observed in retrosplenial cortex, though activation was also greater for city streets than rooms. These results suggest that activation in both cortical areas is primarily related to analysis or representation of local 3-D space. The results are not consistent with hypotheses that these areas reflect panoramic spatial volume, an artificial versus natural category distinction, an indoor versus outdoor distinction, or the number of explicit objects depicted in a scene image.     

Eccentricity biases of object categories are evident in visual working memory

In high-order object areas, face-selective areas prefer centrally presented stimuli, whereas building-selective areas prefer peripherally presented stimuli (Levy et al., 2001). We investigated whether this eccentricity bias was also evident in visual working memory. In Experiment 1, we found that working memory performance for faces decreased towards the periphery while the performance for buildings remained unchanged across different eccentricities. To rule out the possibility that lower level features influence these results, we manipulated the spatial frequency of faces and buildings (Experiment 2) and the spatial layout information of the buildings (Experiment 3). In both of the experiments, we replicated the results of Experiment 1, even when these lower level features of stimuli were controlled. Consistent with previous findings, the current results suggest that each object category is processed in a different manner depending on the eccentricity. This eccentricity bias is likely the result of how the high-order object areas represent different object categories.     

我国农村地区婴幼儿的喂养问题与对策

喂养不当是导致婴幼儿生长发育不良及营养障碍性疾病的主要原因。婴幼儿的喂养问题在我国农村地区尤为突出,主要表现在喂养方式、添加辅食和喂养行为等方面。文章重点围绕上述3个方面展开分析、提出对策,以期为政府决策、儿童保健人员及喂养者提供参考。     

Full scenes produce more activation than close-up scenes and scene-diagnostic objects in parahippocampal and retrosplenial cortex: an fMRI study

We used fMRI to directly compare activation in two cortical regions previously identified as relevant to real-world scene processing: retrosplenial cortex and a region of posterior parahippocampal cortex functionally defined as the parahippocampal place area (PPA). We compared activation in these regions to full views of scenes from a global perspective, close-up views of sub-regions from the same scene category, and single objects highly diagnostic of that scene category. Faces were included as a control condition. Activation in parahippocampal place area was greatest for full scene views that explicitly included the 3D spatial structure of the environment, with progressively less activation for close-up views of local scene regions containing diagnostic objects but less explicitly depicting 3D scene geometry, followed by single scene-diagnostic objects. Faces did not activate parahippocampal place area. In contrast, activation in retrosplenial cortex was greatest for full scene views, and did not differ among close-up views, diagnostic objects, and faces. The results showed that parahippocampal place area responds in a graded fashion as images become more completely scene-like and include more explicit 3D structure, whereas retrosplenial cortex responds in a step-wise manner to the presence of a complete scene. These results suggest scene processing areas are particularly sensitive to the 3D geometric structure that distinguishes scenes from other types of complex and meaningful visual stimuli.     

An initial survey of fractional graph and table area in behavioral journals

This study examined the fractional graph area (FGA), the proportion of page space used to display statistical graphics, in 11 behavioral journals and places behavior analysis on a continuum with other natural, mathematical, and social science disciplines. The composite FGA of all 11 journals puts behavior analysis within the range of the social sciences, whereas the composite FGA of the most established and preeminent behavioral journals positions behavior analysis within the range of the natural sciences. In addition, fractional table area (FTA), the proportion of page space used to display tables, generally is higher in behavioral journals with lower degrees of FGA, a result that replicates previous research.