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41.
Five-year-old children were tested for perceptual trading relations between a temporal cue (silence duration) and a spectral cue (F1 onset frequency) for the “say-stay” distinction. Identification functions were obtained for two synthetic “say-stay” continua, each containing systematic variations in the amount of silence following the /s/ noise. In one continuum, the vocalic portion had a lower F1 onset than in the other continuum. Children showed a smaller trading relation than has been found with adults. They did not differ from adults, however, in their perception of an “ay-day” continuum formed by varying F1 onset frequency only. The results of a discrimination task in which the two acoustic cues were made to “cooperate” or “conflict” phonetically supported the notion of perceptual equivalence of the temporal and spectral cues along a single phonetic dimension. The results indicate that young children, like adults, perceptually integrate multiple cues to a speech contrast in a phonetically relevant manner, but that they may not give the same perceptual weights to the various cues as do adults.  相似文献   
42.
This research had two aims. The first was to test three explanations of performance on N-term series tasks by young children: the labeling model of B.DeBoysson-Bardies and K. O'Regan (1973), Nature (London), 246, 531–534, the sequential-contiguity model of L. Breslow (1981, Psychological Bulletin, 89, 325–351), and the ordered array or image model of C. A. Riley and T. Trabasso (1974, Journal of Experimental Child Psychology, 17, 187–202). In the first experiment, 5-year-old children were taught additional premises which would interfere with labeling and sequential-contiguity processes, but not with forming an ordered array. Reasoning performance was essentially comparable to previous results with the paradigm, thus supporting the ordered array model. The second aim was to reexamine children's ability to learn sets of premises which can be assembled into an ordered array, since there was reason to believe that previous studies had created false positives. In the second experiment, 3- to 7-year-old children were taught either overlapping (a > b, b > c, …) or nonoverlapping (a > b, c > d, …) premises. Overlapping premises can be integrated into an ordered array (a, b, c, d, e), but nonoverlapping premises cannot. However, the overlapping condition proved more difficult, and the success rate for preschoolers (312- to 412-year-olds) was of zero order. This raises doubts about their ability to learn a set of premises of the kind required for transitive inference. These doubts were strengthened by the third experiment which showed that when premises were not presented in serial order, preschool (312- to 412-year-old) children could not learn the premises of an N-term series task.  相似文献   
43.
This study investigated the effect of television-mediated aggression and real-life aggression on the behavior of Lebanese children. The sample consisted of 48 boys and 48 girls of Lebanese origin who were students in an elementary school in Beirut, Lebanon. After controlling for pre-experimental aggression, the subjects were randomly assigned to one of the following treatment conditions: human-film aggression, cartoon-film aggression, neutral film, or real-life (act of war) aggression. The results indicated that boys as a group were more aggressive than girls and exhibited more imitative aggression after viewing both violent film and real-life violence. Girls were not more violent after viewing filmed aggression but were affected by the real-life violence. Comparisons of Bandura's work within the Lebanese culture are made.  相似文献   
44.
The functional significance of learned population differences in male song in the white-crowned sparrow was explored in natural populations using playback tests. Laboratory results have shown that learning of the population-specific song seems to take place in early life and is strongly dependent upon the nature of the auditory experience at that time. However, the varied results of recent studies make it difficult to reach a confident conclusion about the ecological functions of song learning. The present research took advantage of naturally occurring variation in the differences between songs of adjacent populations to determine a function relating degree of difference in song to intensity of territorial singing elicited. Applying a typological evaluation of syllable structure to the four segments of the song allowed a crude quantitative ranking of the differences between local songs and playback stimuli. These results, together with those of other studies, suggest a unimodal aggressive response function of males to songs of other males. A maximum response to songs slightly different from the local song environment suggests that male exclusion based upon acquired song components may contribute to the maintenance of discrete and stable song dialects.  相似文献   
45.
Three experiments are described which elaborate some of the conditions under which rats will contact and manipulate a periodically presented retractable lever. Experiment 1 demonstrated that (i) initial manipulative oral and manual contact with the lever was facilitated if the rat had previous experience of food delivery in the experimental chamber; (ii) persistence in contacting the lever on successive presentations was a function of whether food continued to be presented in the experimental environment; and (iii) food satiation significantly reduced the tendency of the rat to contact the lever even though an expectancy of food had previously been established under conditions of food deprivation. Experiment 2 suggested that the tendency to approach and contact the lever was in part a function of the local moment-to-moment conditional probability of food delivery. Experiment 3 found that the probability of contacting the lever was higher during presentation of an auditory CS signaling a high rate of food delivery than during stimuli signaling no food at all. These results are interpreted as suggesting that the food-signaling aspects of an appetitive CS and that CS's ability to generate signal-directed behaviors are experimentall separable properties.  相似文献   
46.
The effects of flavor preexposure and test interval on conditioned taste aversions were examined in four experiments. In the first three experiments, prior experience with a flavor different from that used as a conditioned-stimulus (CS) produced attenuated aversions when testing occurred after a 1-day interval but not after a 21-day interval. Preexposure to the same stimulus used as a CS produced attenuated aversions at both 1- and 21-day intervals. In Experiment 4, a delay interval between flavor preexposure and conditioning eliminated the attenuating effect of preexposure, but only when different stimuli were used for preexposure and conditioning. These data could not be easily accounted for by contemporary interpretations of preexposure as an event that interferes with subsequent acquisition of a conditioned aversion. An alternative retrieval interference hypothesis was outlined.  相似文献   
47.
This paper explores the vertices of Jung's, Anzaldúa's and Benjamin's distinct ontologies and the way in which they connect in the shared recognition that what has been estranged in human history is enigmatically lodged in the world's fabric today. Cultural distress, in other words, is the outcome of what has become repudiated in the self and the collective across time. From this perspective, the paper argues that we have a collective responsibility to listen to the claims of the dead laid bare in moments of contemporary real-world danger and it elaborates the psychical dimensions of being that are cultivated in times of danger. The author contends that these psychical presences are the dead of human history including our ancestral heritage that linger and possibly may penetrate our awareness. They haunt and hold a potential to animate our movement towards a sublimatory process that can be seen as a precursor to social responsiveness and action. The author explores this through her own experience with an example of the spawning of spiritual activism within the socio-political maelstrom of AIDS.  相似文献   
48.
W.E.B. Du Bois was thoroughly ambivalent about the political significance of American Black churches regarding their role in challenging racial inequality. He saw them as integral to Black social life, but also as failing to live up to their potential as drivers of liberation. And, while he focused primarily on Black churches within the United States, Du Bois was also committed to Black liberation on a global level. This suggests great potential for applying DuBois’ analyses of Black religion to the question of transnational religious and racial solidarities and the global political salience of “the Black Church” as a category. In this context, this article explores the significance of DuBois’ work for analyzing the category of “the Black Church.” It does so through a comparative case study of African American Christian engagement with the issue of Israel and Palestine, with four case studies ranging from African American Christian Zionists to Palestinian solidarity activists. Across these cases, the analysis highlights the ways that the history, identity, and mission of “the Black Church” are invoked in the context of Palestine and Israel. It argues that “the Black Church” is best understood as a contested category of collective religious and racial identity.  相似文献   
49.
This paper examines the effect of spectators on women’s football games. COVID-19 and related restrictions provide a unique opportunity with an adequate sample size to test the effect of lockdown on sports activities. Studies have recently exploited this opportunity for men’s football to better understand the potential causes of home advantage and, more specifically, assess the psychological consequences when matches are played without supporters. Despite the increased scientific interest, there was only one paper that focused on women’s football. Therefore, we aim to contribute to this research field by considering matches from four major European women’s football leagues. The findings suggest that for three of these leagues, lockdown has a statistically significant effect on the sanctioned yellow cards by either reducing the number of yellow cards sanctioned to the away teams or increasing the number of yellow cards sanctioned to the home teams. Nonetheless, lockdown does not affect any final match outcomes; therefore, it does not significantly affect the magnitude of home advantage for women’s games.  相似文献   
50.
ObjectivesThe aim of this study was to compare three different modes of an acute bout of exercise – endurance, strength, and coordination – in their effects on adolescents' attention.DesignThis was a preregistered, prospective, randomized intervention study with four groups and two distinct measurement occasions.MethodEighty adolescent students aged 15–18 years were randomized to one of three exercise intervention groups (endurance, strength, coordination) or to a non-exercise, control group. The exercise interventions lasted for 25 min. The random assignment to the study groups was stratified according to participants' age and gender. Before and after the exercise intervention, all participants completed the revised d2-test of attention. A 4 × 2 repeated measures ANOVA with contrast-coded test was used as the main analysis method.ResultsAttentional test performance increased from before to after the exercise intervention for all exercise groups, as compared with the control group. The three exercise groups improved equally and did not differ in their attentional scores after the intervention.ConclusionsAn acute bout of exercise was in general beneficial for adolescent students' attention, while the mode of the provided exercise training was not decisive. School directors and teachers are encouraged to incorporate exercise-related breaks into their school plan.  相似文献   
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