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101.
In order to determine the reflectance of a surface, it is necessary to discount luminance changes produced by illumination variation, a process that requires the visual system to respond differently to luminance changes that are due to illumination and reflectance. It is known that various cues can be used in this process. By measuring the strength of lightness illusions, we find evidence that straightness is, used as a cue: When a boundary is straight rather than curved, it has a greater tendency to be discounted, as if it were an illumination edge. The strongest illusions occur when a boundary has high contrast and has multiple X-junctions that preserve a consistent contrast ratio.  相似文献   
102.
This experiment addresses the question of what makes a working memory measure a good predictor of higher-level abilities. Verbal and visuospatial processing episodes were interleaved with distinct verbal and visuospatial storage episodes to form four complex span tasks. Although these measures were reliable predictors of reading and mathematics ability in children, they were no more predictive of these abilities than corresponding simple span tasks involving storage alone. However, when individual differences in storage ability and processing capacity were controlled for, residual variance in complex span performance was related to academic ability in some cases. These findings indicate that complex span tasks are multiply determined, and that differences in task structure can dramatically influence the relative importance of these multiple constraints and the predictive power of a complex span measure.  相似文献   
103.
Neurologically normal individuals exhibit strong leftward response biases during free-viewing perceptual judgments of brightness, quantity, and size. When participants view two mirror-reversed objects and they are forced to choose which object appears darker, more numerous, or larger, the stimulus with the relevant feature on the left side is chosen 60-75% of the time. This effect could be influenced by inaccurate judgments of the true centre-point of the objects being compared. In order to test this possibility, 10 participants completed three visual bisection tasks on stimuli known to elicit strong leftward response biases. Participants were monitored using a remote eye-tracking device and instructed to stare at the subjective midpoint of objects presented on a computer screen. Although it was predicted that bisection errors would deviate to the left of centre (as is the case in the line bisection literature), the opposite effect was found. Significant rightward bisection errors were evident on two of the three tasks, and the leftward biases seen during forced-choice tasks could be the result of misjudgments to the right of centre on these same tasks.  相似文献   
104.
This paper reports on an evaluation of a financial education-training program for residents of New York who had filed for bankruptcy. Over 400 individuals divided into three groups (trained debtors, untrained debtors, and non-debtors) completed identical questionnaires approximately three months apart. Trained debtors took the pretest before training and the post-test after training. Results revealed that trained debtors' financial knowledge increased after training compared with untrained and non-debtors. Trained debtors showed more negative attitudes towards unnecessary spending compared with the other two groups and reported less intention to buy than non-debtors reported. Self-reported behaviors showed significant changes in the desired direction for trained debtors' use of credit cards (i.e. number owned, purchases, and balance amount), paying bills, budgeting, and borrowing from predatory lenders. Implications for pending legislation are discussed.  相似文献   
105.
106.
A confirmatory model integrating Japanese ethnicity, cultural identity, and depression was developed (N = 140). The model incorporated the Center for Epidemiologic Studies-Depression Scale (CES-D), Major Life Events Scale, and Japanese Cultural Scale. Japanese American adolescents scored higher on the Japanese Cultural Scale and reported fewer depressive symptoms on the CES-D total and on 2 of the 3 CES-D factors than part-Japanese American adolescents. Predictors for depression were being Japanese American vs. part-Japanese American, female gender, and culturally intensified events. A significant interaction of behavior by self-identification was noted. The model had good overall fit and suggested that the formation of cultural identity may contribute to depressive symptoms experienced by adolescents, particularly adolescents of mixed heritage.  相似文献   
107.
Bottlenose dolphins are unusual among non-human mammals in their ability to learn new sounds. This study investigates the importance of vocal learning in the development of dolphin signature whistles and the influence of social interactions on that process. We used focal animal behavioral follows to observe six calves in Sarasota Bay, Fla., recording their social associations during their first summer, and their signature whistles during their second. The signature whistles of five calves were determined. Using dynamic time warping (DTW) of frequency contours, the calves signature whistles were compared to the signature whistles of several sets of dolphins: their own associates, the other calves associates, Tampa Bay dolphins, and captive dolphins. Whistles were considered similar if their DTW similarity score was greater than those of 95% of the whistle comparisons. Association was defined primarily in terms of time within 50 m of the mother/calf pair. On average, there were six dolphins with signature whistles similar to the signature whistles of each of the calves. These were significantly more likely to be Sarasota Bay resident dolphins than non-Sarasota dolphins, and (though not significantly) more likely to be dolphins that were within 50 m of the mother and calf less than 5% of the time. These results suggest that calves may model their signature whistles on the signature whistles of members of their community, possibly community members with whom they associate only rarely.  相似文献   
108.
Emotion theories commonly postulate that emotions impose coherence across multiple response systems. However, empirical support for this coherence postulate is surprisingly limited. In the present study, the authors (a) examined the within-individual associations among experiential, facial behavioral, and peripheral physiological responses during emotional responding and (b) assessed whether emotion intensity moderates these associations. Experiential, behavioral, and physiological responses were measured second-by-second during a film that induced amusement and sadness. Results indicate that experience and behavior were highly associated but that physiological responses were only modestly associated with experience and behavior. Intensity of amusement experience was associated with greater coherence between behavior and physiological responding; intensity of sadness experience was not. These findings provide new evidence about response system coherence in emotions.  相似文献   
109.
The lateralization of cognitive abilities is influenced by a number of factors, including handedness, sex, and developmental maturation. To date, a small number of studies have examined sex differences in the lateralization of cognitive and affective functions, and in only few of these have the developmental trajectories of these lateralized differences been mapped from childhood through early adulthood. In the present study, a cross-sectional design was used with healthy children (n=7), adolescents (n= 12), and adults (n= 10) who underwent functional magnetic resonance imaging (fMRI) during a task that required perceiving fearful faces. Males and females differed in the asymmetry of activation of the amygdala and prefrontal cortex across the three age groups. For males, activation within the dorsolateral prefrontal cortex was bilateral in children, right lateralized in adolescents, and bilateral in adults, whereas females showed a monotonic relationship with age, with older females showing more bilateral activation than younger ones. In contrast, amygdala activation was similar for both sexes, with bilateral activation in children, right-lateralized activation in adolescents, and bilateral activation in adults. These results suggest that males and females show different patterns of lateralized cortical and subcortical brain activation across the period of development from childhood through early adulthood.  相似文献   
110.
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