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221.
To cope with environmental variability, animals should gather and use information to reduce uncertainty. In insect parasitoids, associative learning has been widely documented in the context of host foraging. However, despite its potential adaptive value, the insect food searching strategy and cues used to search are poorly understood. In this study, we examined the ability of hymenopteran Venturia canescens females to associate food to a visual cue. To broaden the scope of our results, experiments were performed with both arrhenotokous (sexual) and thelytokous (asexual) individuals. The wasps showed innate attraction for yellow and orange stimuli when presented versus blue stimuli. When trained to associate a food reward with one of the attractive colours (orange), they significantly moved from a distance towards the colour previously associated with food. The choice of the innately preferred colour (yellow) was not modified by associative learning. In the context of food foraging, this study is the first to show associative learning using visual stimuli in a parasitoid and active choice of this colour. This ability gives new insights concerning potential food sources for V. canescens in the field, since flowers are sugar sources, which emit colour signals.  相似文献   
222.
Recently, A. J. Fridlund (e.g., 1994) and others suggested that facial expressions of emotion are not linked to emotion and can be completely accounted for by social motivation. To clarify the influence of social motivation on the production of facial displays, we created an explicit motivation by using facial inhibition instructions. While facial electromyographic activity was recorded at three sites, participants saw humorous video stimuli in two conditions (inhibition, spontaneous) and neutral stimuli in a spontaneous condition. Participants showed significantly more EMG activity in the cheek region and less EMG activity in the brow region when they tried to completely inhibit amused expressions as compared with the neutral control task. Our results suggest that explicit motivation in the sense of voluntary control is not sufficient to mask the effects of spontaneous facial activation linked to humorous stimuli.  相似文献   
223.
When animals encounter a task they have solved previously, or the same problem appears in a different apparatus, how does memory, alongside behavioural traits such as persistence, selectivity and flexibility, enhance problem-solving efficiency? We examined this question by first presenting grey squirrels with a puzzle 22 months after their last experience of it (the recall task). Squirrels were then given the same problem presented in a physically different apparatus (the generalisation task) to test whether they would apply the previously learnt tactics to solve the same problem but in a different apparatus. The mean latency to success in the first trial of the recall task was significantly different from the first exposure but not different from the last exposure of the original task, showing retention of the task. A neophobia test in the generalisation task suggested squirrels perceived the different apparatus as a different problem, but they quickly came to apply the same effective tactics as before to solve the task. Greater selectivity (the proportion of effective behaviours) and flexibility (the rate of switching between tactics) both enhanced efficiency in the recall task, but only selectivity enhanced efficiency in the generalisation task. These results support the interaction between memory and behavioural traits in problem-solving, in particular memory of task-specific tactics that could enhance efficiency. Squirrels remembered and emitted task-effective tactics more than ineffective tactics. As a result, they consistently changed from ineffective to effective behaviours after failed attempts at problem-solving.  相似文献   
224.
The aim of this study was to explore associations between self-esteem, general self-efficacy, and the deep, strategic, and surface approaches to studying. Norwegian occupational therapy students (n?=?125) completed questionnaires measuring study approaches, self-esteem, and general self-efficacy. Regression analyses were used to explore the direct relationships between self-esteem, general self-efficacy and the approaches to studying, after controlling for age, gender, prior higher education, and time spent on independent studying. General self-efficacy displayed positive associations with deep and strategic approaches to studying and a negative relationship with a surface approach to studying. Self-esteem was not significantly associated with approaches to studying.  相似文献   
225.
The neurophysiological and neuroanatomical foundations of developmental language disorder (DLD) are still a matter of dispute. A main argument is that children with DLD show atypical anatomical asymmetries of speech-relevant brain areas, which possibly affect efficient language processing. In contrast to previous anatomical studies in DLD children, this study employed voxel based morphometry (VBM) in order to search for brain anomalies outside the classical language areas. Children with DLD (n=21) and healthy children (n=21) matched for age, sex, hand preference, and education were studied using high-resolution MRI scans. Using a new variant of the voxel-based morphometry technique (augmented VBM), the brains of children with DLD and control children were compared with respect to white matter (WM) and grey matter (GM) differences. In addition, simple hand motor tests were used to uncover possible motor impairments in DLD children. We found decreased WM volumes in a left-hemispheric network comprising the motor cortex, the dorsal premotor cortex, the ventral premotor cortex, and the planum polare on the superior temporal gyrus. In addition, DLD children exhibited motor impairments in most of the applied motor tests. These results provide strong evidence that children with DLD have anomalous anatomy in a left-sided network comprising motor and language areas. Thus, this study supports the suggestion that motor and language functions are equally impaired because the underlying anatomical underpinnings are regionally identical.  相似文献   
226.
Social Psychology of Education - The purpose of this study was to explore associations between school principals’ self-efficacy for instructional leadership, their perceptions of work-related...  相似文献   
227.
Adversities refer to events that are characterized by perceived or actual threat to human functioning. Often considered deleterious for health and well-being, recent work supports an alternative picture of the effects of adversity on human functioning, such that a moderate amount of adversity – when compared with none or high levels – can be beneficial. We extend this body of work in the current study by considering the breadth or type of adversities experienced simultaneously (referred to as polyadversity), with a focus on individual profiles of lifetime adversities. Latent class analysis was employed to explore different configurations of lifetime adversity experiences in two independent samples and examine how these latent classes differed with regard to resilience resources (i.e., optimism, hope, self-efficacy, and bounce-back ability). University students (N = 348) and members from the broader community (N = 1,506) completed measures of lifetime adversity exposure and resilience resources. Three polyadversity classes were revealed in each sample, with both producing a high and a low polyadversity class. The third class differed between samples; in the student sample, this class represented experiences of vicarious adversity, whereas in the community sample, it represented moderate levels of exposure to adversity. Support for the adaptive nature of a moderate amount of adversity exposure was found in the community sample but not in the student sample. This study produces initial evidence of how lifetime adversity experiences group together and how class membership is related to resilience resources.  相似文献   
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229.
OBJECTIVE: This study is aimed at enhancing understanding prenatal screening decision making through testing a hypothesized decision model based on decision theory and health behavior theory. DESIGN: We obtained questionnaires from 1,666 pregnant women who were offered prenatal screening for Down's syndrome. Path analysis (using LISREL) resulted in a final model with reasonable model fit, which was verified by split-sample cross-validation. MAIN OUTCOME MEASURES: These included perceived probability, perceived severity, attitude toward termination, response efficacy, attitude toward prenatal screening, subjective norm, child-related anxiety, and intention to undergo prenatal screening. RESULTS: Attitude toward termination of pregnancy, perceived test efficacy, and subjective norm regarding the desirability of having prenatal screening determined a woman's attitude toward having a prenatal test. Anxiety was influenced by perceived risk and perceived severity of having a child with Down's syndrome, and by subjective norm, but this appeared to be a weak predictor of intention to test. Pregnant women with a positive attitude toward prenatal screening, and who perceived a subjective norm in favor of undergoing prenatal screening, showed a greater intention to have prenatal screening done. CONCLUSION: These findings suggest that more attention should be paid toward the values and social context of pregnant women during the counseling process.  相似文献   
230.
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