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In this article, we examine the performance of different eye blink detection algorithms under various constraints. The goal of the present study was to evaluate the performance of an electrooculogram- and camera-based blink detection process in both manually and conditionally automated driving phases. A further comparison between alert and drowsy drivers was performed in order to evaluate the impact of drowsiness on the performance of blink detection algorithms in both driving modes. Data snippets from 14 monotonous manually driven sessions (mean 2 h 46 min) and 16 monotonous conditionally automated driven sessions (mean 2 h 45 min) were used. In addition to comparing two data-sampling frequencies for the electrooculogram measures (50 vs. 25 Hz) and four different signal-processing algorithms for the camera videos, we compared the blink detection performance of 24 reference groups. The analysis of the videos was based on very detailed definitions of eyelid closure events. The correct detection rates for the alert and manual driving phases (maximum 94%) decreased significantly in the drowsy (minus 2% or more) and conditionally automated (minus 9% or more) phases. Blinking behavior is therefore significantly impacted by drowsiness as well as by automated driving, resulting in less accurate blink detection.  相似文献   
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Humans possess an invaluable ability of self-expression that extends into visual, literary, musical, and many other fields of creation. More than any other profession, artists are in close contact with this subdomain of creativity. Probably one of the most intriguing aspects of creativity is its negative correlation with the availability of monetary reward. The aim of this study was to investigate the reactivity of the dopaminergic reward system in artists and nonartist controls using the desire-reason-dilemma (DRD) paradigm, which allows separate evaluation of reactivity to the acceptance and rejection of rewards. Using fMRI, blood-oxygen-level-dependent (BOLD) responses were measured in key regions of the reward system, namely the ventral striatum (VS), the ventral tegmental area (VTA), and the anterior ventral prefrontal cortex (AVPFC). In contrast to controls, artists presented significantly weaker VS activation in reward acceptance. Additionally, they showed stronger suppression of the VS by the AVPFC in reward rejection. No other differences in demographic or behavioral data were evidenced. These results support the existence of characteristic neural traits in artists, who display reduced reactions to monetary reward acceptance and increased reactions to monetary reward rejection.  相似文献   
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Visual search is often slow and difficult for complex stimuli such as feature conjunctions. Search efficiency, however, can improve with training. Search for stimuli that can be identified by the spatial configuration of two elements (e.g., the relative position of two colored shapes) improves dramatically within a few hundred trials of practice. Several recent imaging studies have identified neural correlates of this learning, but it remains unclear what stimulus properties participants learn to use to search efficiently. Influential models, such as reverse hierarchy theory, propose two major possibilities: learning to use information contained in low-level image statistics (e.g., single features at particular retinotopic locations) or in high-level characteristics (e.g., feature conjunctions) of the task-relevant stimuli. In a series of experiments, we tested these two hypotheses, which make different predictions about the effect of various stimulus manipulations after training. We find relatively small effects of manipulating low-level properties of the stimuli (e.g., changing their retinotopic location) and some conjunctive properties (e.g., color-position), whereas the effects of manipulating other conjunctive properties (e.g., color-shape) are larger. Overall, the findings suggest conjunction learning involving such stimuli might be an emergent phenomenon that reflects multiple different learning processes, each of which capitalizes on different types of information contained in the stimuli. We also show that both targets and distractors are learned, and that reversing learned target and distractor identities impairs performance. This suggests that participants do not merely learn to discriminate target and distractor stimuli, they also learn stimulus identity mappings that contribute to performance improvements.  相似文献   
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Guided internet CBT (iCBT) is a promising treatment for depression; however, it is less well known through what mechanisms iCBT works. Two possible mediators of change are the acquisition of cognitive skills and increases in behavioral activation. We report results of an 8-week waitlist controlled trial of guided iCBT, and test whether early change in cognitive skills or behavioral activation mediated subsequent change in depression. The sample was 89 individuals randomized to guided iCBT (n = 59) or waitlist (n = 30). Participants were 75% female, 72% Caucasian, and 33 years old on average. The PHQ9 was the primary outcome measure. Mediators were the Competencies of Cognitive Therapy Scale–Self Report and the Behavioral Activation Scale for Depression–Short Form. Treatment was Beating the Blues plus manualized coaching. Outcomes were analyzed using linear mixed models, and mediation with a bootstrap resampling approach. The iCBT group was superior to waitlist, with large effect sizes at posttreatment (Hedges’ g = 1.45). Dropout of iCBT was 29% versus 10% for waitlist. In the mediation analyses, the acquisition of cognitive skills mediated subsequent depression change (indirect effect = -.61, 95% bootstrapped biased corrected CI: -1.47, -0.09), but increases in behavioral activation did not. iCBT is an effective treatment for depression, but dropout rates remain high. Change in iCBT appears to be mediated by improvements in the use of cognitive skills, such as critically evaluating and restructuring negative thoughts.  相似文献   
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Theories of boredom assert that boredom is a product of situational meaninglessness. We conducted two studies to test if the perceived meaningfulness of a situation is associated with state boredom, above and beyond sadness, personality traits, and boredom proneness. In Study 1, 105 participants (72.4% female: mean age?=?33.9 years, SD?=?17.5) described situations in which they experienced boredom, no boredom, engagement, or sadness. They then rated the level of state boredom, sadness, and meaninglessness that they experienced in that situation. As hypothesized, state boredom was associated with situational meaninglessness, before and after controlling for sadness. In Study 2, 148 participants (73.0% female; mean age?=?19.2 years, SD?=?1.8) first provided baseline data on personality traits and boredom proneness. Through a smartphone app-based experience-sampling method, they then responded to a brief questionnaire multiple times a day, across 7 days. The questionnaire asked about the nature of their current activity, whether the activity was done alone or with other people, and their affective state. Results from multilevel modelling of 3022 entries suggest that perceived meaningfulness of the activity was negatively associated with state boredom, above and beyond sadness, personality, and boredom proneness. We also found that being with others during the activity acted as a moderator; activities lower in perceived meaningfulness were associated with higher ratings of state boredom when done with others than when done alone. These results demonstrate that perceptions of meaninglessness characterize state boredom.  相似文献   
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Greater male variability has been established in cognitive abilities and physical attributes. This study investigated sex differences in variability in vocational interests with two large samples (N > 40 000 and N > 70 000). The results show that although men varied more in Realistic and Enterprising interests, women varied more in Artistic and Conventional interests. These differences in variability had considerable influence on the female–male tail ratios in vocational interests that have been found to contribute to reported gender disparities in certain fields of work and academic disciplines. Moreover, differences in means and variability interacted non‐linearly in shaping tail‐ratio imbalances. An age‐specific analysis additionally revealed that differences in variability diminished with age: Older samples showed smaller differences in variance in Realistic, Artistic, and Social interests than younger samples. Thus, I found no evidence that greater male variability applies for vocational interests in general. Copyright © 2015 European Association of Personality Psychology  相似文献   
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