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41.
Seven albino rats were exposed to a multiple schedule of reinforcement in which the two components (fixed interval and extinction) alternated such that a presentation of the extinction component followed each fixed-interval reinforcement. In baseline sessions, the duration of the extinction component was constant and always one-third of the fixed-interval value. Probe sessions contained a probe segment in which the duration of the extinction component was increased; the response rate in fixed-interval components during the probe segment was compared with the response rate in the segments preceding and following the probe. The effect of increasing the duration of the extinction component was studied under three values of fixed interval: 30 s, 120 s, and 18 s, in three successive conditions. Response rate within fixed intervals was a direct function of duration of the extinction component. Pausing at the beginning of the fixed interval decreased as extinction duration increased. These effects were larger and more consistent for the shorter fixed-interval values (18 s and 30 s). These results indicate a functional relation between relative component duration and responding. For the component providing more frequent reinforcement, this could be stated as an inverse relationship between relative component duration and response rate. This relation is similar to findings regarding the ratio of trial and intertrial duration in Pavlovian conditioning procedures, and suggests that behavioral contrast may be related to Pavlovian contingencies underlying the multiple schedule.  相似文献   
42.
Two different concepts of distinguishability are often mixed up in attempts to derive in quantum mechanics the (anti)symmetry of the wave function from indistinguishability of identical particles. Some of these attempts are analyzed and shown to be defective. It is argued that, although identical particles should be considered as observationally indistinguishable in (anti)symmetric states, they may be considered to be conceptually distinguishable. These two notions of (in)distinguishability have quite different physical origins, the former one being related to observations while the latter has to do with the preparation of the system.  相似文献   
43.
While emotions are usually treated as internal states, it is possible to view them as social relationships. From this perspective, the different emotions are not primarily understood in terms of facial expression, physiological pattern, hedonic tone, or level of arousal, but as different transformations of the relationship between person and other. To demonstrate the value of this approach, judgments of the similarity between different emotions were submitted to multidimensional scaling. It is shown that the resulting dimensions describe different aspects of the relation between self and other. These dimensions provide us with a taxonomy of emotions that makes some important distinctions between closely related emotions and leads to some interesting predictions about personality differences.The authors would like to thank David Stevens for his assistance with the statistical analysis, Eric de Rivera for drafting the three-dimensional figures, and James D. Laird and Shula Sommers for their helpful commentary.  相似文献   
44.
Food deprived, heterogeneous strain (HS/IBG) mice were trained on two different discrimination tasks for food reinforcement. In one experiment animals were trained to make spatial discriminations in a T maze. Immediately after training they were given subcutaneous injections of either substance P (1 ng/g) or vehicle. Twenty-four hours later the animals were given reversal training in the same maze. The results showed that substance P-treated animals took significantly longer to acquire the reversal habit than did control mice. In a second experiment, animals were trained to make visual discriminations in a T maze. Immediately after reaching acquisition criterion animals were injected with either substance P (1 ng/g) or vehicle. Different groups of mice were retrained on the same task either 1, 2, 3, or 7 days after original learning. Savings scores were calculated and, at every interval, substance P-treated mice retained the task better than control animals. One interpretation of these data is that substance P-treated mice remembered the original task significantly better than vehicle-injected control animals.  相似文献   
45.
Research shows that parents have a strong influence on the party preferences of their children. Yet little is known about how such preferences are transmitted in multiparty systems with weak party identification and high electoral volatility. We propose a model of intergenerational transmission that includes both direct effects of parents' party preferences on those of their children, as well as indirect effects through left–right and issue positions. We test this model with original survey data of Dutch adolescents (14–20 years old) and their parents (N = 751 adolescent-parent pairs). We find two paths through which parents exert influence on the party preferences of their adolescent children. On the first path, parental party preferences function as a direct predictor of adolescent party preferences. On the second path, adolescent left–right and issue positions function as a mediator between parental left–right and issue positions and adolescent party preferences, with the effect of left–right positions being stronger than that of issue positions. The frequency with which adolescents discuss political topics with their parents moderates these effects.  相似文献   
46.
Animal Cognition - The alarm calls of nonhuman primates are occasionally cited as functionally equivalent to lexical word meaning in human language. Recently, however, it has become increasingly...  相似文献   
47.
The aim of this study is to gain empirical knowledge about how the Bible functions in the context of Protestant Christian primary schools in the Netherlands. It presents the results of an empirical explorative and qualitative study on the perceptions of teachers and school administrators (directors and internal supervisors) on the goals of Bible use in Protestant primary education, as well as the roles of teachers and pupils, and how these can be understood in terms of religious pedagogical models and theories. Five small focus group interviews with teachers and six interviews with school administrators revealed a variety of goals teachers hold regarding Bible use in education and a variety of divisions of teacher–learner roles in this regard. The findings also show some particular characteristics when compared with secondary schools.  相似文献   
48.
This study explores consumers' behaviour regarding sustainable mobility options. A mixed-methods approach was adopted to examine the impact of bio-altruistic values, egoistic values, environmental attitudes, attitudes regarding sustainable mobility, perceived behavioural control and subjective norms on the likelihood of choosing sustainable mobility options. To collect the data, an online survey was applied to a sample of 645 Portuguese consumers, which included one single non-mandatory open-ended question to understand which factors could contribute to increase respondents' likelihood to choose more sustainable transport modes. As most studies in the mobility field are quantitative, combining both quantitative and qualitative data provided a greater in-depth analysis with richer findings. Firstly, findings revealed that attitudes towards sustainable mobility, subjective norms, perceived behaviour control, and egoistic values influence the likelihood of choosing sustainable mobility options. However, environmental attitudes, altruistic and biospheric values do not impact this choice. Secondly, consumers highlight that the existence of a broad public transport network, safe bicycle lanes, and accessible prices would contribute to their likelihood of adopting more sustainable mobility behaviours. The content analysis of 402 answers allowed to discover new dimensions that influence sustainable mobility behaviour, such as safety, respect towards bicycle users, mindset adjustment, willpower, and especially physical efforts associated with long distances, bad weather, orography, and the difficulty to transport materials or other people. Based on both quantitative and qualitative findings, the paper provides key recommendations for politicians, urban planners, and transport organisations, that according to respondents, would contribute to increase their use of sustainable mobility.  相似文献   
49.
Grefte  Job de 《Argumentation》2023,37(1):53-68

A Persistent Interlocutor (PI) is someone who, in argumentative contexts, does not cease to question her opponent’s premises. The epistemic relevance of the PI has been debated throughout the history of philosophy. Pyrrhonians famously claim that our inability to dialectically vindicate our claims against a PI implies scepticism. Adam Leite disagrees (2005). Michael Resorla argues that the debate is based on a false premise (2009). In this paper, I argue that these views all fail to accurately account for the epistemic relevance of the PI. I then briefly present an account that aims to do better in this regard, based on the modal notion of safety. On the account proposed, the PI does not violate epistemic or dialectical norms. Rather, her behaviour tends to be epistemically perverse in the sense that it wastes cognitive resources. Perhaps surprisingly, this defect turns out not to be unique to the PI.

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50.
Judgments of the acceptability of correct, word order reversed, and semantically anomalous sentences were elicited from 2- and 3-year-old children in a game played with hand puppets. All of the sentences used were simple imperatives and each child was asked to correct those he called wrong. Performance on the judgment task was correlated with each child's mean length of utterance and with his comprehension of reversible active and passive sentences. Only the linguistically most advanced children were able to make a significant number of appropriate judgments and corrections of reversed word order imperatives. Less developed children could appropriately judge and correct semantically anomalous but not incorrect word order imperatives. The importance of semantic as opposed to syntactic factors in children's judgments of the acceptability of sentences is stressed.This research was supported in part by PHS Grant HD-02908 from the National Institute of Child Health and Development. Roger Brown is the principal investigator.  相似文献   
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