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241.
The ability to wait for a reward is a necessary capacity for economic transactions. This study is an age-related investigation of children's ability to delay gratification in an exchange task requiring them to wait for a significant reward. We gave 252 children aged 2-4 a small piece of cookie, then offered them an opportunity to wait for a predetermined delay period before exchanging it for a larger one. In a first experiment, the children had to exchange the initial food item for rewards two, four or eight times larger. Results showed that children aged 3-4 years old sustained longer time lags for larger rewards than for smaller rewards. This effect was not found in 2-year-old subjects. In a second experiment, a reward 40 times larger than the initial piece was offered to determine the maximum waiting time that children could sustain. All age groups increased their performances. Older children were more successful at waiting, but some children as young as 2 years old were able to tolerate delays of up to 16 min. Older children who chose to give up waiting earlier than their known capacity demonstrated anticipation skills which had not been seen in younger children, showing that they had anticipated an increase in the time lag, and that they had considered both time and reward value when making their decision. Despite the age effect, we did not establish any limits for delaying gratification in children. This study may have educational implications for dealing with behavioral misconduct, which is known to be related to impulsivity control in young children.  相似文献   
242.
We describe a multiple-route model of reading development in which coarse-grained orthographic processing plays a key role in optimizing access to semantics via whole-word orthographic representations. This forms part of the direct orthographic route that gradually replaces phonological recoding during the initial phases of reading acquisition. The model predicts distinct developmental trajectories for pseudo-homophone and transposed-letter effects - two benchmark phenomena associated with phonological recoding and coarse-grained orthographic processing, respectively. Pseudo-homophone effects should decrease over the first years of reading acquisition, whereas transposed-letter effects should initially increase. These predictions were tested in a lexical decision task with 334 children in grades 1-5, and 29 skilled adult readers. In line with the predictions, we found that the pseudo-homophone effect diminished as reading level increased, whereas the transposed-letter effect first increased and then diminished.  相似文献   
243.
Deacon SH  Benere J  Castles A 《Cognition》2012,122(1):110-117
There is increasing evidence of a relationship between orthographic processing skill, or the ability to form, store and access word representations, and reading ability. Empirical research to date has not, however, clarified the direction of this relationship. We examined this question in a three-year longitudinal study of children from Grades 1 to 3. We included standard measures of orthographic processing skill, at both the lexical and sublexical level, and word reading accuracy, as well as controls of vocabulary, non-verbal reasoning, and phonological awareness. In all analyses, word reading predicted progress in acquiring orthographic processing skill, regardless of grade level or orthographic processing measure. In contrast, orthographic processing skill did not predict progress in word reading. Our results suggest that, between Grades 1 and 3, children acquire orthographic processing skill through their reading and that this ability, as characterized by the most common tasks used to date, does not play an independent role in supporting reading acquisition.  相似文献   
244.
We describe a leaky competing accumulator (LCA) model of the lexical decision task that can be used as a response/decision module for any computational model of word recognition. The LCA model uses evidence for a word, operationalized as some measure of lexical activity, as input to the YES decision node. Input to the NO decision node is simply a constant value minus evidence for a word. In this way, evidence for a nonword is a function of time from stimulus onset (as in standard deadline models) modulated by lexical activity via the competitive dynamics of the LCA. We propose a simple mechanism for determining the value of this constant online during the first trials of a lexical decision experiment, such that the model can rapidly optimize speed and accuracy in discriminating words from nonwords. Further optimization is achieved via trial-by-trial adjustments in response criteria as a function of task demands and list context. We show that the LCA model can simulate mean response times and response distributions for correct and incorrect YES and NO decisions for a number of benchmark experiments that have been shown to be fatal for deadline models of lexical decision. Finally, using lexical activity calculated by a computational model of word recognition as input to the LCA decision module, we provide the first item-level simulation of both word and nonword responses in a large-scale database.  相似文献   
245.
Since 2000, surveys on academic achievement show gender inequalities in favor of girls in the school setting. The aim of the present study was to examine if gender stereotypes about academic abilities that are usually considered as fully demonstrated in the literature have to be updated. Three hundred ninety-eight French fifth graders from a medium-sized provincial town answered a questionnaire designed to examine, both with direct and indirect measures, if they hold different gender stereotypes concerning mathematics and reading depending on target’s age (children vs. adults). As expected, results showed that participants, regardless of their gender, were aware of a math-ability stereotype favorable to men when the stereotyped targets were adults. When the stereotyped targets were children and young adolescents, the math-ability stereotype was less clear. Participants believed that people think that girls succeed as well as boys in math. Concerning reading-ability, participants reported the “usual” stereotype favorable to females, regardless of the stereotyped target’s age (child or adult). Together these results suggest that academic gender stereotypes have to be reconsidered. The math-ability stereotype targeting children and favorable to both genders seems to show an improvement of the French girls’ reputation in mathematics. Moreover, the reputation of French boys in this domain seems to be poorer than reported in previous research.  相似文献   
246.
Mixed martial arts (MMA) have become a fast-growing worldwide expansion of martial arts competition, requiring high level of skill, physical conditioning, and strategy, and involving a synthesis of combat while standing or on the ground. This study quantified the effort-pause ratio (EP), and classified effort segments of stand-up or groundwork development to identify the number of actions performed per round in MMA matches. 52 MMA athletes participated in the study (M age = 24 yr., SD = 5; average experience in MMA = 5 yr., SD = 3). A one-way analysis of variance with repeated measurements was conducted to compare the type of action across the rounds. A chi-squared test was applied across the percentages to compare proportions of different events. Only one significant difference (p < .05) was observed among rounds: time in groundwork of low intensity was longer in the second compared to the third round. When the interval between rounds was not considered, the EP ratio (between high-intensity effort to low-intensity effort plus pauses) was 1:2 to 1:4. This ratio is between ratios typical for judo, wrestling, karate, and taekwondo and reflects the combination of ground and standup techniques. Most of the matches ended in the third round, involving high-intensity actions, predominantly executed during groundwork combat.  相似文献   
247.
The objective of this study is to analyze the mediating role of intrinsic and extrinsic job satisfaction in the relationship between the 2 dimensions of work-family conflict-family interfering with work (FIW) and work interfering with family (WIF)-and general job satisfaction. Step-by-step hierarchical regression analyses were carried out on a sample of 151 men and women from a Spanish public organization. The results confirmed the mediating role of intrinsic job satisfaction in the case of FIW. This highlights the importance of taking into account the level of satisfaction with the intrinsic facets of one's job as a measure for understanding why FIW has a negative impact on general job satisfaction.  相似文献   
248.
To assess associations between social relationships and consultation for symptoms of depression, data from a representative sample of 2,811 French-speaking community-dwelling older adults in Québec were used. Less than half of the older adults meeting DSM criteria for depression (N = 379; 47.1%) had sought consultation about their depression-relevant symptoms in the preceding 12 months. Having a cohabitant partner or having children were not associated with frequency of consultation for women. Men without a partner tended to consult more frequently than men with a cohabiting partner (OR = 2.5; 95% CI = 0.81, 7.88). None of the men without a confidant had consulted. Among the 67 men with a confidant, consultation was more frequent among those not cohabiting with a partner (70%) than among those with a cohabiting partner (46%). The influence of social relationships on consultation for depression differed in men and women in this population of depressed elderly people in Québec.  相似文献   
249.
When people's health is threatened, they generally develop illness perceptions to make sense of their illness. The Illness Perception Questionnaire (IPQ-R), developed by Moss-Morris et al (2002), has been widely used in many countries to measure such representations. However, since studies in this crucial research area are lacking in Sweden a Swedish version of IPQ-R was validated with a focus on the seven subscales: timeline acute/chronic, timeline cyclical, consequences, personal control, treatment control, illness coherence and emotional representations. Using confirmatory factor analysis, the aim of the present study was to validate the internal structure of the Swedish version in a sample of 202 persons (144 men and 58 women) who had been diagnosed with myocardial infarction four months earlier. Additionally, inter-correlations among the seven subscales and external concurrent validity were also investigated. The results of confirmatory factor analysis revealed that, in line with the English version of the IPQ-R, the specified seven-factor model had a satisfactory fit. One item was however not considered reliable and was therefore excluded from the instrument. The internal consistency (Cronbach's alpha coefficients) and the inter-factor correlations were relatively similar to those reported in the validation study of the original English IPQ-R. In tests of concurrent validity, the seven IPQ-R subscales were, as hypothesized, mainly associated with external variables. To conclude, the Swedish version of the IPQ-R's seven dimensions, with one item removed, (total 37 items) was found to be a reliable and valid measure of illness perception.  相似文献   
250.
Saccadic endpoint variability is often viewed as the outcome of neural noise occurring during sensorimotor processing. However, part of this variability might result from operant learning. We tested this hypothesis by reinforcing dispersions of saccadic amplitude distributions, while maintaining constant their medians. In a first experiment we reinforced the least frequent saccadic amplitudes to increase variability, and then reinforced the central part of the amplitude distributions to reduce variability. The target was placed at a constant distance from the fovea after the saccade to maintain the postsaccadic visual signal constant and an auditory reinforcement was delivered depending on saccadic amplitude. The second experiment tested the effects of the contingency. We reinforced high levels of variability in 4 participants, whereas 4 other participants were assigned to a yoked control group. On average, saccadic amplitude standard deviations were doubled while the medians remained mostly unchanged in the experimental participants in both experiments, and variability returned to baseline level when low variability was reinforced. In the control group no consistent changes in amplitude distributions were observed. These results, showing that variability can be reinforced, challenge the idea of a stochastic neural noise. We instead propose that selection processes constrain saccadic amplitude distributions.  相似文献   
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