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151.
Two experiments were conducted to compare choices between sequences of reinforcers in pigeon (Experiment 1) and human (Experiment 2) subjects, using functionally analogous procedures. The subjects made pairwise choices among 3 sequence types, all of which provided the same overall reinforcerment rate, but differed in their temporal patterning. Token reinforcement schedules were used in both experiments and the type of exchange schedule varied across blocks of sessions. Some conditions permitted immediate exchange of tokens for consumable reinforcers (food for pigeons, video access for humans); in other conditions, tokens accumulated and were exchanged for consumable reinforcers only at the end of the sequence. Choice patterns in the immediate-exchange conditions were generally similar across species, with both pigeons and humans preferring sequences with the shortest delay to the initial reinforcer in the series. The results are broadly consistent with models of temporal discounting expanded to include the impact of sequences of delayed reinforcers acting in parallel from the time of the choice. Preferences were less consistent with discounting models in the delayed exchange conditions. Questionnaire data gathered at the end of the experiment were consistent with prior results of questionnaire studies, but showed no straightforward relation to the observed choice patterns, urging caution in the extrapolation of results from one decision-making domain to the other.  相似文献   
152.
Thinking about the abstract concept power may automatically activate the spatial up-down image schema (powerful up; powerless down) and consequently direct spatial attention to the image schema-congruent location. Participants indicated whether a word represented a powerful or powerless person (e.g. ‘king’ or ‘servant’). Following each decision, they identified a target at the top or bottom of the visual field. In Experiment 1 participants identified the target faster when their spatial position was congruent with the perceived power of the preceding word than when it was incongruent. In Experiment 2 ERPs showed a higher N1 amplitude for congruent spatial positions. These results support the view that attention is driven to the image schema congruent location of a power word. Thus, power is partially understood in terms of vertical space, which demonstrates that abstract concepts are grounded in sensory-motor processing.  相似文献   
153.
Male aggressiveness is a complex behavior influenced by a number of genetic and non-genetic factors. Traditionally, the contribution of each of these factors has been established from experiments using artificially selected strains for high/low aggressive phenotypes. However, little is known about the factors underlying aggressive behavior in natural populations. In this study, we assess the influence of genetic background vs. postnatal maternal environment using a set of cross-fostering experiments between two wild-derived inbred strains, displaying high (STRA, derived from Mus musculus domesticus) and low (BUSNA, derived from Mus musculus musculus) levels of aggressiveness. The role of maternal environment was tested in males with the same genetic background (i.e. strain origin) reared under three different conditions: unfostered (weaned by mother), infostered (weaned by an unfamiliar dam from the same strain), and cross-fostered (weaned by a dam from a different strain). All males were tested against non-aggressive opponents from the A/J inbred strain. Resource-holding potential was assessed through body weight gains and territory ownership. The STRA males were shown to be aggressive in both neutral cage and resident-intruder tests. On the contrary, the BUSNA males were less aggressive in all tests. We did not find a significant effect of postnatal maternal environment; however, we detected significant maternal effect on body weight with differences between the strains, fostering type and interactions between these factors. We conclude that the aggressiveness preserved in the two strains has significant genetic component whose genetic basis can be dissected by quantitative trait loci analysis.  相似文献   
154.
In a recent critique Boles and Barth (2011) argue that their prior study investigating asymmetry/performance relationships (Boles, Barth, & Merrill, 2008) uncovered the “true” association (i.e., negative correlation) between lateralization of visual lexical processes and word recognition performance. They contend that our study reporting positive correlations of lexical asymmetry and reading performance (Chiarello et al., 2009) was flawed and hence inconclusive. In this response we address the two major objections raised by Boles and Barth (2011) regarding our selection of tasks and asymmetry measures. We conclude that the Boles and Barth principle of task purity is not relevant to the stated aims of our investigation, and that our linear regression method of measuring asymmetry is valid given the high level of accuracy for the tasks we reported. Because the aims of each investigation differed, we argue that it is unwise to attempt to fit each study into the framework favored by Boles and Barth (2011).  相似文献   
155.
Laypersons' chains of reasoning in explaining recent influenza outbreaks are investigated. Drawing on social representations theory, fundamental worldviews, that is, the belief in a dangerous world (BDW), are postulated to anchor explanations of disease origins, which in turn affect perceived effectiveness of protection measures. Our study, based on a longitudinal survey among the general public in Switzerland, showed that the lower people's BDW scores, the more they appeal to natural origins to explain outbreaks and the more they perceive official protection measures as effective. The higher people's BDW scores, the more they explain outbreaks via hygienic origins, which are linked with out‐group discrimination measures, and conspiracy origins, which are linked with lower perceived effectiveness of aid intervention measures. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
156.
The present research examined the dynamic interplay between the framing of one's progress from an initial state toward an end state (i.e., framed as the distance traveled from the initial state to the current state -‘to-date’ versus framed as the distance left from the current state to the end state -‘to-go’) and construal level in influencing motivation in goal pursuit. In three experiments we found that both state and chronic differences in experienced construal level modulate the impact of progress framing on motivation at a specific stage in goal pursuit, i.e., when consumers are halfway between the initial and end state, but is less consequential at the initial or end stages. This modulation shows that type of framing only affected motivation of people with an abstract, but not a concrete mindset. Under these conditions, progress framed in terms of to-date produced increased motivation compared to a to-go frame. Moreover, perceived goal distance was found to mediate the impact of progress framing on motivation for individuals with an abstract, but not a concrete mindset.  相似文献   
157.
The essential activity of a manager is decision making, which is becoming more and more complex, mainly in the multi‐criteria problems. Multi‐choice goal programming (MCGP) is considered as a robust tool in operational research to solve this type of problem. However, in real world problems, determining precise targets for the goals is a difficult task. To deal with such situation, Tabrizi introduced and used in 2012 the concept of membership functions in the MCGP model in order to model the targets fuzziness of each goal. In their model, they considered just only one type of functions (triangular form), which does not reflect adequately the decision maker's preferences that are considered as an essential element for modelling the goal's fuzziness. Their model is called Fuzzy MCGP. In this paper, new ideas are presented to reformulate MCGP model to tackle all types of functions by introducing the (decision maker's) preferences. The concept of indifference thresholds is used in the new formulation for characterizing the imprecision and the preferences associated with all types of the goals. The proposed formulation provides useful insight about the solution of a new class of problems. A numerical example is given to demonstrate the validity and strength of the new formulation. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
158.
Past research shows that European Americans tend to take a first‐person perspective to understand the self and are unlikely to align the inside look with the outside gaze, whereas Asians tend to take a third‐person perspective and are likely to shift their inside look in the direction of the outsize gaze. In three experiments, we compared Asians and European Americans' self‐perceptions when the presence of their parents in the background of self‐perception was primed or otherwise. Without the priming, both European Americans and Asians viewed themselves more positively from their own perspective than from their parents' perspective. With the priming, only Asians lowered the positivity of their self‐perceptions to match the perceived positivity of the self in the parents' perspective. These results suggest that Asians do not have a static, passive tendency to assimilate their self‐views into the perceived external assessments of the self. Rather, their self‐views are fluid and flexible.  相似文献   
159.
ObjectiveThe primary aim of the present study was to investigate whether construing action abstractly versus concretely increases physical activity over a one-week period.Design and methodAn experimental study was conducted in which participants were asked to commit to engaging in physical activity at least four times in the coming week. After making this commitment, participants were assigned randomly to think about the concrete procedures or the abstract purpose of their actions. Additionally, in an attempt to induce differences in level of goal conflict, participants were assigned randomly to receive a reminder of a different or consistent goal. The main outcome variable of interest was the number of minutes spent on physical activity over the following 7-day period.ResultsConsistent with the hypothesis, participants in the abstract condition reported engaging in significantly more minutes of physical activity than did those in the concrete condition. Level of goal conflict did not significantly impact physical activity. The effect of abstract versus concrete thinking on physical activity also was related to the processing of negative affect.ConclusionBy providing evidence that construing action abstractly impacts physical activity, the present investigation makes an important addition to research aiming to identify effective means of increasing physical activity.  相似文献   
160.
ObjectiveTo determine if the level of competitive sport in which people participate is related to levels of perfectionistic strivings and perfectionistic concerns in sport.DesignA cross-sectional correlational design was employed.MethodA total of 383 (245 female, 138 male) undergraduate students (M age = 20.99 years, SD = 3.40) identified the level of competitive sport in which they were currently involved (i.e., no sport, recreational sport, moderately competitive sport, and highly competitive sport). Participants also completed a domain-specific measure of perfectionism that assessed perfectionistic strivings and perfectionistic concerns in sport.ResultsResults from sequential regression analyses indicated that competitive sport level explained a significant amount of variance in perfectionistic strivings (p < .001) when the overlap between perfectionistic strivings and perfectionistic concerns was controlled. Competitive sport level did not explain a significant amount of variance in perfectionistic concerns when the overlap between perfectionistic strivings and perfectionistic concerns was controlled.ConclusionsFindings indicate that higher (more competitive/serious) levels of competitive sport are associated with higher perfectionistic strivings in sport. Discussion focusses on the potential roles that (a) the competitive sport environment may have upon the development of perfectionistic strivings in sport, and (b) perfectionistic strivings may play in enabling athletes to compete at higher levels of competitive sport.  相似文献   
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