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821.
The ability to discriminate between quantities has been observed in many species. Typically, when an animal is given a choice between two sets of food, accurate performance (i.e., choosing the larger amount) decreases as the ratio between two quantities increases. A recent study reported that elephants did not exhibit ratio effects, suggesting that elephants may process quantitative information in a qualitatively different way from all other nonhuman species that have been tested (Irie-Sugimoto et al. in Anim Cogn 12:193-199, 2009). However, the results of this study were confounded by several methodological issues. We tested two African elephants (Loxodonta africana) to more thoroughly investigate relative quantity judgment in this species. In contrast to the previous study, we found evidence of ratio effects for visible and nonvisible sequentially presented sets of food. Thus, elephants appear to represent and compare quantities in much the same way as other species, including humans when they are prevented from counting. Performance supports an accumulator model in which quantities are represented as analog magnitudes. Furthermore, we found no effect of absolute magnitude on performance, providing support against an object-file model explanation of quantity judgment.  相似文献   
822.
The goal of three experiments was to study whether rats are aware of the difference between absence of events and lack of evidence. We used a Pavlovian extinction paradigm in which lights consistently signaling sucrose were suddenly paired with the absence of sucrose. The crucial manipulation involved the absent outcomes in the extinction phase. Whereas in the Cover conditions, access to the drinking receptacle was blocked by a metal plate, in the No Cover conditions, the drinking receptacle was accessible. The Test phase showed that in the Cover conditions, the measured expectancies of sucrose were clearly at a higher level than in the No Cover conditions. We compare two competing theories potentially explaining the findings. A cognitive theory interprets the observed effect as evidence that the rats were able to understand that the cover blocked informational access to the outcome information, and therefore the changed learning input did not necessarily signify a change of the underlying contingency in the world. An alternative associationist account, renewal theory, might instead explain the relative sparing of extinction in the Cover condition as a consequence of context change. We discuss the merits of both theories as accounts of our data and conclude that the cognitive explanation is in this case preferred.  相似文献   
823.
Research on children's emotional competence has received considerable attention in the last decade, including the role of language. Language competence (LC) and emotional competence (EC) comprise multiple components. These components and their specific interrelations have not been studied sufficiently. In our study, we examined relations between multiple components of LC and EC in a sample of 210 school-age children. Five measures represented LC: receptive vocabulary, verbal fluency, literacy, narrative structure, and the narrative use of evaluative devices. Four measures represented EC: expressive emotion vocabulary, declarative emotion knowledge, awareness of mixed emotions, and facial emotion recognition. Results showed strong positive correlations between LC and EC ranging between r = .12 and r = .45. In particular, receptive vocabulary and literacy were closely related to emotion knowledge and awareness of mixed emotions. A confirmatory factor analysis revealed that there is a common general ability factor for LC and EC. We discuss why receptive vocabulary and literacy might be so strongly related to emotion knowledge in school-age children. Our findings have implications for developmental psychologists, educational research, and speech-language pathologists.  相似文献   
824.
The facial feedback effect (e.g., Strack et al., 1988) is explored in three experiments. It was found that when someone lowers their eyebrows, following instructions, their mood becomes more negative. If, however, they are instructed to raise their eyebrows they become more surprised by facts. Finally, if people are instructed to wrinkle their noses, then odors are evaluated as more unpleasant. While providing further diverse evidence for facial feedback, the experiments are also considered in the context of facial muscular paralysis induced as part of cosmetic treatments using botulinum toxin. The research presented here supports the previously suggested idea that such treatments could reduce depression, but other possible psychological impacts of such treatments are considered. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   
825.
This study examined the collective behaviour of the police during a football match at the 2006 Football World Cup. What peacekeeping and aggravating processes could be identified and what were their consequences? Data were collected using observation and field interviews. Some critical situations could have escalated into riots; however, the police showed trust in the majority of the supporters' intentions to be peaceful. Distrust was reserved for selected individuals who were under surveillance. This, together with tactics involving using different forces for different tasks and an overall organisational strategy focusing on the festivity of the event, was the main reason for the peaceful outcome. A friendly but firm approach was successful in keeping the peace. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
826.
Age of acquisition (AoA) ratings based on a 1-7 scale for 3,000 disyllabic words were obtained from 32 participants. We demonstrate that these estimates are both reliable and valid. These estimates add to those collected on monosyllabic words and are of value to researchers interested in factors that contribute to word processing. They also can be used in regression analyses on measures obtained from large databases, and can be used in conjunction with imageability ratings for the same word corpus to differentiate AoA from imageability.  相似文献   
827.
This paper explores several paths a distinctive third wave of extended cognition might take. In so doing, I address a couple of shortcomings of first- and second-wave extended cognition associated with a tendency to conceive of the properties of internal and external processes as fixed and non-interchangeable. First, in the domain of cognitive transformation, I argue that a problematic tendency of the complementarity model is that it presupposes that socio-cultural resources augment but do not significantly transform the brain??s representational capacities during diachronic development. In this paper I show that there is available a much more dynamical explanation??one taking the processes of the brain??s enculturation into patterned practices as transforming the brain??s representational capacities. Second, in the domain of cognitive assembly, I argue that another problematic tendency is an individualistic notion of cognitive agency, since it overlooks the active contribution of socio-cultural practices in the assembly process of extended cognitive systems. In contrast to an individualistic notion of cognitive agency, I explore the idea that it is possible to decentralize cognitive agency to include socio-cultural practices.  相似文献   
828.
The serial reaction time (SRT) task is a simple procedure in which participants produce differentiated responses to each of a series of stimuli presented at varying locations. Learning about stimulus order is revealed through decreased latencies for structured versus randomized sequences. Although widely used with humans and well suited to nonhumans, this paradigm is little used in comparative research. In the present article, we describe an SRT procedure that uses colored circles as stimuli, a circular layout of locations, and symmetrical joystick deflections as responses. In two experiments, we showed that four rhesus macaques (Macaca mulatta) learned to track sequences up to eight items long, with three animals showing faster responding to repeating sequences than to randomized versions. After extended training, these participants also showed evidence of faster responding at all positions within repeating sequences. This method minimizes response effort, equates effort and travel distance across stimulus locations, and is applicable to any joystick-capable species.  相似文献   
829.
Little longitudinal research has examined progression to more severe bipolar disorders in individuals with "soft" bipolar spectrum conditions. We examine rates and predictors of progression to bipolar I and II diagnoses in a nonpatient sample of college-age participants (n = 201) with high General Behavior Inventory scores and childhood or adolescent onset of "soft" bipolar spectrum disorders followed longitudinally for 4.5 years from the Longitudinal Investigation of Bipolar Spectrum (LIBS) project. Of 57 individuals with initial cyclothymia or bipolar disorder not otherwise specified (BiNOS) diagnoses, 42.1% progressed to a bipolar II diagnosis and 10.5% progressed to a bipolar I diagnosis. Of 144 individuals with initial bipolar II diagnoses, 17.4% progressed to a bipolar I diagnosis. Consistent with hypotheses derived from the clinical literature and the Behavioral Approach System (BAS) model of bipolar disorder, and controlling for relevant variables (length of follow-up, initial depressive and hypomanic symptoms, treatment-seeking, and family history), high BAS sensitivity (especially BAS Fun Seeking) predicted a greater likelihood of progression to bipolar II disorder, whereas early age of onset and high impulsivity predicted a greater likelihood of progression to bipolar I (high BAS sensitivity and Fun-Seeking also predicted progression to bipolar I when family history was not controlled). The interaction of high BAS and high Behavioral Inhibition System (BIS) sensitivities also predicted greater likelihood of progression to bipolar I. We discuss implications of the findings for the bipolar spectrum concept, the BAS model of bipolar disorder, and early intervention efforts.  相似文献   
830.
Little empirical knowledge about unemployed adults exists during a time when this group needs substantial career assistance. Because there is greater empirical understanding of college student career development compared with what is known about unemployed adults, a chi square and analyses of covariance were used to compare the career thinking, self‐efficacy, and interests of 169 unemployed adults seeking public job center assistance with that of 200 college students. Additionally, a diverse sample of 2,444 unemployed adults is demographically reviewed. Unemployed adults reported a higher level of Realistic interests and similar levels of negative career thinking and career decision‐making self‐efficacy compared with college students.  相似文献   
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