The study investigated the effectiveness of different camouflage designs using a computational image quality index. Camouflaged human targets were presented on a natural landscape and the targets were designed to be similar to the landscape background with different levels of background similarity as estimated by the image index. The targets were presented in front of the observer (central 0 degrees) or at different angles in the left (-7 degrees, -14 degrees, -21 degrees) or right (+7 degrees, +14 degrees, +21 degrees) visual fields. The observer had to detect the target using peripheral vision if the target appeared in the left and right visual fields. The camouflage effectiveness was assessed by detection hit rates, detection times, and subjective ratings on detection confidence and task difficulty. The study showed that the psychophysical measures correlated well with the image similarity index, suggesting a potentially more efficient camouflage effectiveness assessment tool if the relationship between the psychophysical results and the index can be quantified in the future. 相似文献
Disadvantageous decision making is cited as one of the premier problems in childhood development, underlying risky behavior and causing adolescents to make poor choices that could prove detrimental later in life. However, there are relatively few studies looking at the development of decision making in children and adolescents, and fewer still comparing it with the performance trajectories of more typically developing cognitive functions. In the current study, we measured the affective decision-making abilities of children and adolescents 8- to 17-years-old using the Iowa Gambling Task (IGT; Bechara, 2007) in conjunction with a battery of established cognitive neuropsychological assessments. In contrast to the typical linear development of executive functions, affective decision-making abilities progressed in a J-shaped curve. Younger, more developmentally naive children performed better on the IGT than older, early-adolescent individuals, with performance becoming advantageous again toward the end of the teenage years. This trajectory is thought to coincide with asymmetric neural development in early adolescents, with relatively overactive striatal regions creating impulsive reward-driven responses that may go unchecked by the slower developing inhibitive frontal cortex. This trajectory is in stark contrast with the linear development of memory, speed of processing, and other cognitive abilities over the ages. 相似文献
The theory of planned behavior has been applied to sports and exercise behaviors. According to this theory, human intention to take action in a specific context is guided by three antecedents: attitude, subjective norm, and perceived behavioral control. Behavioral intention mediates the relationships between these three considerations and its ultimate performance. However, this theory has seldom been applied to the behaviors of spectators of sporting events. A sample of 269 volleyball spectators in Taiwan was studied to examine whether people's intention mediated their attitudes, subjective norms, and perceived behavioral control toward a given behavior, watching the 2010 Fédération Internationale de Volleyball World Grand Prix in Taipei. Regression analyses did not support behavioral intention as a mediator. This result is discussed in the context of planned behavior. 相似文献
Within-subjects procedures with rats assessed the associative structures acquired during conditioning trials in which the interval between the stimuli and food was either short or long (i.e., A-10 s→food and B-40 s→food). In Experiments 1 and 2, after these conditioning trials, A and B served as second-order reinforcers for 2 further stimuli (i.e., X→A and Y→B); whereas Experiment 3 used a sensory preconditioning procedure in which X→A and Y→B trials occurred before the conditioning trials, and rats were finally tested with X and Y. In each experiment, Y elicited greater responding at test than did X. This finding supports the contention that the long-lived trace of B (associated with food on B-40 s→food trials) is more similar to the memory of B that was associatively provoked by Y, than is the short-lived trace of A (associated with food on A-10 s→food trials) to the memory of A that was associatively provoked by X. These conclusions were reinforced by the effects of a neural manipulation that disrupted discrimination learning involving the short traces of stimuli but not the long traces of the same stimuli. 相似文献
Exposure to severe air pollution produces neuroinflammation and structural brain alterations in children. We tested whether patterns of brain growth, cognitive deficits and white matter hyperintensities (WMH) are associated with exposures to severe air pollution. Baseline and 1 year follow-up measurements of global and regional brain MRI volumes, cognitive abilities (Wechsler Intelligence Scale for Children-Revised, WISC-R), and serum inflammatory mediators were collected in 20 Mexico City (MC) children (10 with white matter hyperintensities, WMH+, and 10 without, WMH−) and 10 matched controls (CTL) from a low polluted city. There were significant differences in white matter volumes between CTL and MC children - both WMH+ and WMH− - in right parietal and bilateral temporal areas. Both WMH− and WMH+ MC children showed progressive deficits, compared to CTL children, on the WISC-R Vocabulary and Digit Span subtests. The cognitive deficits in highly exposed children match the localization of the volumetric differences detected over the 1 year follow-up, since the deficits observed are consistent with impairment of parietal and temporal lobe functions. Regardless of the presence of prefrontal WMH, Mexico City children performed more poorly across a variety of cognitive tests, compared to CTL children, thus WMH+ is likely only partially identifying underlying white matter pathology. Together these findings reveal that exposure to air pollution may perturb the trajectory of cerebral development and result in cognitive deficits during childhood. 相似文献
Given the prevalence of imagery appeals in today’s marketplace, the current research studies the role of mental imagery in how consumers process and react to advertisements with different numbers of ad claims. Past research has proposed “three” as the magical number of ad claims that maximizes persuasion, with more than three ad claims increasing skepticism and reducing evaluation. In the current research, we replicate this so-called “charm of three” effect, but only when consumers do not engage in mental imagery; when they do, however, we find that the effect is moderated, in that more ad claims beyond three produces more favorable product evaluation. Additionally, we provide evidence that the moderating effect of mental imagery is driven by transportation and skepticism toward the ad claims, with mental imagery increasing transportation and decreasing skepticism when there are more than three ad claims. Our research contributes to a better understanding of the “charm of three” effect, its boundary conditions, and underlying mechanism. 相似文献
Applied Research in Quality of Life - There is increased social concern regarding children’s weight in China, but there is a relative lack of research concerning its social determinants.... 相似文献
In China, rural–urban migration is one of major influences on the mental health of migrant and left-behind children. Literature suggests that the perception of discrimination is an important factor that influences the mental health of these children. The present research explores (1) whether migrant children and left-behind children are different in the relationship between the perception of discrimination and mental health, and (2) whether the relationship between the perception of discrimination and mental health of these children is moderated by gender and age. Using a meta-analytic technique, the authors included 26 studies (generating 48 independent samples) with a total sample size of 28,883 participants. Results showed that the perception of discrimination of migrant children was negatively correlated with positive indicators of mental health, and it has a stronger effect than left-behind children; the perception of discrimination of migrant children was positively correlated with negative indicators of mental health, and it has a weaker effect than left-behind children. Additionally, gender moderated the relationship between the perception of discrimination and the positive indicators of mental health among left-behind children, while age moderated such relationship among migrant children.