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When attention is oriented to a peripheral cue, the processing of nearby stimuli is facilitated. This brief period of facilitation is followed by a long-lasting inhibitory effect, during which there is a delayed response to stimuli presented at a previously cued location. Although the mechanisms underlying the facilitatory effect of attentional orienting/reorienting in threedimensional (3-D) space have been documented, there is not yet consensus as to how attention orients/reorients in depth during the later inhibitory phase (i.e., inhibition of return [IOR]). In the present study, by incorporating the Posner exogenous cueing paradigm into a virtual 3-D environment, we aimed to investigate whether an IOR effect occurs when attention orients and reorients at the uncued depth in the same hemispace, and whether the IOR effects are the same or different when attention orients/reorients along different trajectories in 3-D space. Our results showed asymmetrical spatial IOR effects when attention was oriented/ reoriented at the uncued depth in the same hemispace. Spatial IOR was depth-specific when targets appeared in the near depth plane, whereas it was not depth-specific when targets appeared in the far depth plane. Apart from these results, we also found that attention oriented/reoriented at the same depth but in a different hemispace experienced a reduction in IOR size, thus indicating that the direction-specific spatial IOR mechanisms when attention orients/reorients along different trajectories are different. Taken together, our results suggest that spatial IOR is not entirely Bdepth-blind,^and that the ecological importance of the 3-D world influences the direction of attentional shifts of spatial IOR in 3-D space. Studies of visuospatial attention in two-dimensional (2-D) space have shown that when attention is oriented to a peripheral cue, if the stimulus onset asynchrony between the cue and target is less than 300 ms, processing of a target appearing at a precued peripheral location is facilitated (as compared with the response to a target appearing at a novel location). A brief period of facilitation is followed by a long-lasting inhibitory effect in which there is a delayed response to stimuli presented at the previously cued location. This long-lasting inhibitory effect is called Binhibition of return^ (IOR;Posner & Cohen, 1984; see Klein, 2000).Studies of visuospatial attention have primarily focused on 2-D space (Corbetta, Kincade, Lewis, Snyder, & Sapir, 2005;Corbetta, Kincade, Ollinger, McAvoy, & Shulman, 2000;Corbetta, Patel, & Shulman, 2008;Corbetta & Shulman, 2002;Lupiáñez et al., 2004;Mayer, Seidenberg, Dorflinger, & Rao, 2004;Spence, Lloyd, McGlone, Nicholls, & Driver, 2000;Zhang, Zhou, & Zhang, 2012); however, though these 2-D spatial representations show us how attentional orienting responds to the directions of objects, they tell us little about how it is affected by objects' distances. Humans live in a

In order to learn the impact of MOOCs, we conducted a SPOC experiment on the course of Data Structures and Algorithms in Peking University. In this paper, we analyze student online activities, test scores, and two surveys using statistical methods (t-test, analysis of variance, correlation analysis and OLS regression) to understand what factors will foster improvements in student learning. We find that the "SPOC + Flipped" is a helpful mode to teach algorithm, time spent on the course and students' confidence had a positive impact on learning effect, and SPOC resource should be made full use of.

We measured the eccentricity effect of deformation thresholds of circular contours for two types of the radial frequency (RF) patterns with their centers at the fixation point: constant circular contour frequency (CCF) RF patterns and constant RF magnified (retino-cortical scaling) RF patterns. We varied the eccentricity by changing the mean radius of the RF patterns while keeping the centers of the RF patterns at the fixation point. Our peripheral stimulus presentation was distinguished from previous studies which have simply translated RF patterns at different locations in the visual field. Sensitivity for such shape discrimination fell off as the moderate and high CCF patterns were presented on more eccentric sites but did not as the low CCF patterns. However, sensitivity held constant as the magnified RF patterns were presented on more eccentric sites, indicating that the eccentricity effects observed for the high and moderate CCF patterns were neutralized by retinocortical mapping. Notably, sensitivity for the magnified RF patterns with large radii (4°–16°) presented in the peripheral field revealed a similar RF dependence observed for RF patterns with small radii (0.25°–1.0°) presented at the fovea in previous studies.