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961.
Attentional biases may influence the eye-movements made when judging bodies and so alter the visual information sampled when making a judgment. This may lead to an overestimation of body size. We measured the eye-movements made by 16 anorexic observers and 16 age-matched controls when judging body size and attractiveness. We combined behavioural data with a novel eye-movement analysis technique that allowed us to apply spatial statistical techniques to make fine spatial discriminations in the pattern of eye-movements between our observer groups. Our behavioural results show that anorexic observers overestimate body size relative to controls and find bodies with lower body mass indexes more attractive. For both judgments, the controls' fixations centre on the stomach, but the anorexic observers show a much wider fixation pattern extending to encompass additional features such as the prominence of the hip and collar bones. This additional visual information may serve to alter their behavioural judgments towards an overestimation of body size and shift their ideal body size towards a significantly lower value.  相似文献   
962.
Change in strategies is often mentioned as a source of memory development. However, though performance in working memory tasks steadily improves during childhood, theories differ in linking this development to strategy changes. Whereas some theories, such as the time-based resource-sharing model, invoke the age-related increase in use and efficiency of a strategy of active maintenance of memory traces, other theories, such as the task-switching model, do not mention strategy change. According to these models, either the cognitive load of the task or the duration of maintenance would account for recall performance. In the present study, we varied orthogonally these 2 factors. The results revealed that a different and unique factor affected recall performance at different ages: the duration of maintenance at age 6 and the cognitive load at age 7. As described by the task-switching model, younger children would not implement any maintenance activities while performing a concurrent task, their memory traces suffering from a time-based decay. This suggests that an increasing capacity of cognitive monitoring allows children to shift from this passive maintenance of memory traces to the active refreshing thereof at around the age of 7, reunifying the 2 current accounts of working memory development as 2 developmental stages.  相似文献   
963.
This study compared the effects of a computer-based stimulus equivalence protocol to a traditional lecture format in teaching single-subject experimental design concepts to undergraduate students. Participants were assigned to either an equivalence or a lecture group, and performance on a paper-and-pencil test that targeted relations among the names of experimental designs, design definitions, design graphs, and clinical vignettes was compared. Generalization of responding to novel graphs and novel clinical vignettes, as well as the emergence of a topography-based tact response after selection-based training, were evaluated for the equivalence group. Performance on the paper-and-pencil test following teaching was comparable for participants in the equivalence and lecture groups. All participants in the equivalence group showed generalization to novel graphs, and 6 participants showed generalization to novel clinical vignettes. Three of the 4 participants demonstrated the emergence of a topography-based tact response following training on the stimulus equivalence protocol.  相似文献   
964.
Two nationally representative epidemiological samples (the National Longitudinal Alcohol Epidemiological Survey and the National Epidemiological Survey of Alcohol and Related Conditions) have been used to track changes in the prevalence of alcohol use disorders (AUDs) between 1992 and 2002 in the United States. Strikingly, estimates from these two data sets suggest that the lifetime prevalence of AUD increased by approximately 67% (from 18.2% to 30.3%) during this time frame. This article explores potential reasons for these discrepant estimates. Analyses indicated that a vast majority of change in lifetime AUD occurred with respect to alcohol abuse and not alcohol dependence. Most of this increase in abuse was attributable to self-reported changes in hazardous use that did not track with other archival measures of outcomes related to hazardous use in the population. Key methodological differences regarding the frequency requirements for prior-to-past-year alcohol abuse appeared to explain most of the discrepancy in lifetime AUD estimates. These findings, in conjunction with the relative lack of differences in the 12-month prevalence of AUDs, suggest that the discrepant lifetime estimates are likely due to methodological differences between the two surveys. These findings have important implications for substance use and other psychiatric surveillance and epidemiology where meaningful cross-temporal comparisons are desired.  相似文献   
965.
Three visual priming experiments using three different prime durations (60 ms in Experiment 1, 250 ms in Experiment 2, and 800 ms in Experiment 3) were conducted to examine which properties of morphemes (form and/or meaning) drive developing readers’ processing of written morphology. French third, fifth, and seventh graders and adults (the latter as a control group) performed lexical decision tasks in which targets were preceded by morphological (e.g., tablette–TABLE, “little table–table”), pseudoderived (e.g., baguette–BAGUE, “little stick–ring”), orthographic control (e.g., abricot–ABRI, “apricot–shelter”), and semantic control (e.g., Tulipe–FLEUR, “tulip–flower”) primes. Across all groups, different patterns of priming were observed in both morphological and orthographic/semantic control conditions, suggesting that they all process morphemes as units when reading. In developing readers, the processing of written morphology is triggered by the form properties of morphemes, and their semantic properties are activated later in the time course of word recognition. In adults, patterns of priming were similar except that the activation of the form properties of morphemes decreased earlier in the time course of word recognition. Taken together, these findings indicate that French developing readers process both the form and meaning properties of morphemes when reading and support a progressive quantitative change in the development of morphological processing over the course of reading development.  相似文献   
966.
Studies have demonstrated that maternal stress and perceptions of self-efficacy influence a mother's performance, affecting her ability to interact with her child and to understand and answer his needs. The purpose of this study was to evaluate maternal stress and the perception of self-efficacy in the mothers of infants who are cared for in child-care centers and belong to the poorest segment of the Chilean population. To this end, these aspects were studied in 121 low-income, high-social-risk mothers with children between the ages of 4 and 9 months. The final goal was to generate an explicative model of self-efficacy and maternal stress that considered characteristics of the family and the child. The results revealed that family characteristics - especially household size, per capita incomes and mother age - are more relevant for explaining maternal self-efficacy and stress. The findings and implications for practice are discussed.  相似文献   
967.
Using data from the International Social Survey Programme, this research investigated asymmetric attitudes of ethnic minorities and majorities towards their country and explored the impact of human development, ethnic diversity, and social inequality as country‐level moderators of national attitudes. In line with the general hypothesis of ethnic asymmetry, we found that ethnic, linguistic, and religious majorities were more identified with the nation and more strongly endorsed nationalist ideology than minorities (H1, 33 countries). Multilevel analyses revealed that this pattern of asymmetry was moderated by country‐level characteristics: the difference between minorities and majorities was greatest in ethnically diverse countries and in egalitarian, low inequality contexts. We also observed a larger positive correlation between ethnic subgroup identification and both national identification and nationalism for majorities than for minorities (H2, 20 countries). A stronger overall relationship between ethnic and national identification was observed in countries with a low level of human development. The greatest minority‐majority differences in the relationship between ethnic identification and national attitudes were found in egalitarian countries with a strong welfare state tradition.  相似文献   
968.
The cost of attending to a visual event can be the failure to consciously detect other events. This processing limitation is well illustrated by the attentional blink paradigm, in which searching for and attending to a target presented in a rapid serial visual presentation stream of distractors can impair one's ability to detect a second target presented soon thereafter. The attentional blink critically depends on 'top-down' attentional settings, for it does not occur if participants are asked to ignore the first target. Here we show that 'bottom-up' attention can also lead to a profound but ephemeral deficit in conscious perception: Presentation of a novel, unexpected, and task-irrelevant stimulus virtually abolishes conscious detection of a target presented within half a second after the 'Surprise' stimulus, but only for its earliest occurrences (generally 1 to 2 presentations). This powerful but short-lived deficit contrasts with a milder but more enduring form of attentional capture that accompanies singleton presentations in rapid serial visual presentations. We conclude that the capture of stimulus-driven attention alone can limit explicit perception.  相似文献   
969.
Predicting the consequences of actions is fundamental for skilled motor behavior. We investigated whether motor prediction is influenced by the fact that some movements are easier to perform and stabilize than others. Twelve subjects performed a bimanual rhythmical task either symmetrically or asymmetrically (the latter being more difficult and less stable) while oscillating in each hand an object attached to an elastic cord. Motor prediction was monitored through the adequacy of anticipatory grip force adjustments with respect to the elastic resisting force. Results showed less adequate predictive control during asymmetrical movements (compared with symmetrical ones). Furthermore, switching between modes of coordination induced even larger alterations. An interesting finding was that grip force control did not always stabilize around the expected value after voluntary transition. We conclude that motor prediction is affected by the degree of coordination between the upper limbs and by phase transitions and is prone to carryover effects.  相似文献   
970.
The purpose of this study was to examine the effectiveness of second tier intervention at-risk readers within the context of a Response to Intervention approach. The study was conducted in the Canary Islands (Spain), directed by research team ¨Dificultades de Aprendizaje, Psicolingüística y Nuevas Tecnologías¨ (DEA&NT) from University of La Laguna, and supported by the Government of the Canary Islands. A sample of 1.123 Spanish children from fourteen schools districts were given the Spanish adaptation of The Hong Kong Specific Learning Difficulties Behavior Checklist and children who scored at or above the 75th percentile on the test were classified as "at risk" for early reading difficulties. Half of the students were randomly assigned to a project-based intervention condition where they received small group supplementary intervention for 30 minutes daily using the Prevención de las Dificultades Específicas de Aprendizaje (PREDEA) curriculum from mid to late December and continued until mid June. The other half received whatever remedial services were available at their schools. Results indicated that children who received the PREDEA curriculum had higher scores on the Early Grade Reading Assessment Test (EGRA) on initial sound identification, listening comprehension, letter sound knowledge and oral reading fluency compared to the control group.  相似文献   
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