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981.
Putting ifs to work: goal-based relevance in conditional directives   总被引:1,自引:0,他引:1  
Conditional directives are used by speakers to instruct hearers which actions are to be taken should certain events occur. The authors demonstrate that conditional directives are distinct from indicative conditionals in which speakers predict what is likely to be observed should certain events occur. The 1st set of experiments shows that goal structure determines what information speakers will select to test whether conditional directives have been followed but that these selections do not reflect their interpretations of the deontic necessity and sufficiency of the conditional relation. The 2nd set of experiments shows that formulations of conditional directives differ in how clearly speakers consider them to express their situation-specific intentions and that hearers accurately perceive what speakers intend them to do as a result of these formulations. The authors' findings illustrate a form of social rationality common in everyday interaction, which broadens normative conceptions of conditionals.  相似文献   
982.
A novel attentional capture effect is reported in which visual-verbal serial recall was disrupted if a single deviation in the interstimulus interval occurred within otherwise regularly presented task-irrelevant spoken items. The degree of disruption was the same whether the temporal deviant was embedded in a sequence made up of a repeating item or a sequence of changing items. Moreover, the effect was evident during the presentation of the to-be-remembered sequence but not during rehearsal just prior to recall, suggesting that the encoding of sequences is particularly susceptible. The results suggest that attentional capture is due to a violation of an algorithm rather than an aggregate-based neural model and further undermine an attentional capture-based account of the classical changing-state irrelevant sound effect.  相似文献   
983.
984.
We studied the effects of a selective lesion in rats, with 192-IgG-saporin, of the cholinergic neurons located in the medial septum/diagonal band (MSDB) complex on the acquisition of classical and instrumental conditioning paradigms. The MSDB lesion induced a marked deficit in the acquisition, but not in the retrieval, of eyeblink classical conditioning using a trace paradigm. Such a deficit was task-selective, as lesioned rats were able to acquire a fixed-interval operant conditioning as controls, and was not due to nonspecific motor alterations, because spontaneous locomotion and blink reflexes were not disturbed by the MSDB lesion. The deficit in the acquisition of a trace eyeblink classical conditioning was reverted by the systemic administration of carbachol, a nonselective cholinergic muscarinic agonist, but not by lobeline, a nicotinic agonist. These results suggest a key role of muscarinic denervation on the acquisition of new motor abilities using trace classical conditioning procedures. It might also be suggested that muscarinic agents would be useful for the amelioration of some associative learning deficits observed at early stages in patients with Alzheimer's disease.  相似文献   
985.
Courtship conditioning is an associative learning paradigm in Drosophila melanogaster, wherein male courtship behavior is modified by experience with unreceptive, previously mated females. While the training experience with mated females involves multiple sensory and behavioral interactions, we hypothesized that female cuticular hydrocarbons function as a specific chemosensory conditioned stimulus in this learning paradigm. The effects of training with mated females were determined in courtship tests with either wild-type virgin females as courtship targets, or with target flies of different genotypes that express distinct cuticular hydrocarbon (CH) profiles. Results of tests with female targets that lacked the normal CH profile, and with male targets that expressed typically female CH profiles, indicated that components of this CH profile are both necessary and sufficient cues to elicit the effects of conditioning. Results with additional targets indicated that the female-specific 7,11-dienes, which induce naive males to court, are not essential components of the conditioned stimulus. Rather, the learned response was significantly correlated with the levels of 9-pentacosene (9-P), a compound found in both males and females of many Drosophila strains and species. Adding 9-P to target flies showed that it stimulates courting males to attempt to copulate, and confirmed its role as a component of the conditioned stimulus by demonstrating dose-dependent increases in the expression of the learned response. Thus, 9-P can contribute significantly to the conditioned suppression of male courtship toward targets that express this pheromone.  相似文献   
986.
This study was undertaken to verify the effects of chronic stress and lithium treatments on the hippocampal Na+,K(+)-ATPase activity of rats, as well as to investigate the effects of stress interruption and post-stress lithium treatment on this enzyme activity and on spatial memory. Two experiments were carried out; in the first experiment, adult male Wistar rats were divided into two groups: control and submitted to a chronic variate stress paradigm, and subdivided into treated or not with LiCl. After 40 days of treatment, rats were killed, and Na+,K(+)-ATPase activity was determined. In the second experiment, rats were stressed during 40 days, and their performance was evaluated in the Water Maze task. The stressed group was then subdivided into four groups, with continued or interrupted stress treatment and treated or not with lithium for 30 additional days. After a second evaluation of performance in the Water Maze, rats were killed and Na+,K(+)-ATPase activity was also measured. Results showed an impairment in Na+,K(+)-ATPase activity and in Water Maze performance of chronically stressed rats, which were prevented by lithium treatment and reversed by lithium treatment and by stress interruption. These results suggest that the modulation of Na+,K(+)-ATPase activity may be one of the mechanisms of action of lithium in the treatment of mood disorders.  相似文献   
987.
Volunteerism is a well consolidated social phenomenon in our society. However, its rapid growth in the last few years has complicated the integration of theoretical knowledge and its application in organizational settings. Taking into account that nowadays, one of the chief problems of volunteer organizations is sustained volunteer service, the object of this work is to verify, within the context of the psychosocial model of sustained volunteerism (Vecina, 2001), the type of relation between the experience of positive emotions in volunteers and their intention of remaining in the organization. This work was carried out on a sample of volunteers who had been in service for less than one year prior to this study.  相似文献   
988.
The purpose of this research is to provide information about the state of psychotherapy in Argentina, as well as to study some variables involved in psychologists' evaluation of psychotherapy. A survey of 14 items was elaborated ad-hoc for this purpose, and administered to 226 psychologists from all over the country by mail and, in some cases, personally. Results suggest that the predisposition to apply techniques from different frameworks is associated with the amount of experience and with the perception of a bias concerning other theoretical focuses, although it is not related to the evaluation of the state of psychotherapy. On the other hand, in the view of psychologists, personal aspects of the therapeutic relationship are believed to be the most important factor in patients' change and effective progress.  相似文献   
989.
This study explores the effects of a youth enrichment program on academic motivation and engagement. Fifty-three students aged 14–16 years participated in the Rotary Youth Program of Enrichment (RYPEN). Embedded within the program were workshops revolving around the Student Motivation and Engagement Wheel [Martin (2003a). How to motivate your child for school and beyond. Sydney: Bantam] and strategies aimed at enhancing students’ academic motivation and engagement. Motivation was measured using the Student Motivation and Engagement Scale [Martin (2001). Australian Journal of Guidance and Counselling 11, 1–20; Martin (2003b) Australian Journal of Education, 14, 34–49] at the outset of the program, towards the end of the program, and again 6–8 weeks later. Data showed that there were gains on key facets of students’ motivation by the end of the program – gains that were sustained 6–8 weeks later. These gains were demonstrated by boys and girls. Moreover, when compared to a larger weighted sample (2769 high school students), by Time 2 and also by Time 3, significant declines in motivation had been reversed and any pre-existing advantages or parallel strengths of the RYPEN sample over the weighted sample were maintained. Five facets of the program proposed to have contributed to its effectiveness are: the optimistic expectations held by adults, the program’s focus on mastery, the climate of cooperation and the ensuing sense of belonging, the positive relationships that developed amongst students and between students and adults, and embedding school-related elements within a broader enrichment program. Each of these is discussed.  相似文献   
990.
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