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221.
When conditioning involves a consistent temporal relationship between the conditioned stimulus (CS) and unconditioned stimulus (US), the expression of conditioned responses within a trial peaks at the usual time of the US relative to the CS. Here we examine the temporal profile of responses during conditioning with variable CS-US intervals. We conditioned stimuli with either uniformly distributed or exponentially distributed random CS-US intervals. In the former case, the frequency of each CS-US interval within a specified range is uniform but the momentary probability of the US (the hazard function) increases as time elapses during the trial; with the latter distribution, short CS-US intervals are more frequent than longer intervals, but the momentary probability of the US is constant across time within the trial. We report that, in a magazine approach paradigm, rats' response rates remained stable as time elapses during the CS when the CS-US intervals were uniformly distributed, whereas their response rates declined when the CS-US intervals were exponentially distributed. In other words, the profile of responding during the CS matched the frequency distribution of the US times, not the momentary probability of the US during the CS. These results are inconsistent with real-time associative models, which predict that associative strength tracks the momentary probability of the US, but may provide support for timing models of conditioning in which conditioned responding is tied to remembered times of reinforcement.  相似文献   
222.
Therapeutic alliance research in couple therapy using multiple perspectives and longitudinal data has been sparse. This study used structural equation modelling to explore relationships between changes in alliance and in progress from clients' and therapists' perspective in a fairly large sample of couples (N=195) during the initial stage of therapy at an on‐campus training clinic. Self‐rated alliance was measured after sessions 2 through 4 with the Working Alliance Inventory. There was very little change in alliance over the early sessions of therapy, and changes in alliance did not always account for changes in relationship satisfaction. Husbands' perceptions of satisfaction and alliance seem to play an important role in the dynamics of the therapeutic process. Findings suggest a reciprocal relationship between perceptions of alliance and progress in therapy when combining perceptions of therapists and couple clients. Clinical implications and future research are discussed.  相似文献   
223.
Literature in the area of social networks indicates that increases in perceived social network attitudinal heterogeneity generate increased openness to attitude change. Recent evidence in the area of morality, however, shows that morally based attitudes are particularly resistant to persuasion and can result in the rejection of disagreeing others. Positing that considering morality would reduce network influence, an experiment varied moral cues presented along with a non‐network persuasive message while holding the actual content constant. Results demonstrate that morality and network composition interact to predict persuasion, such that when people are not cued to consider morality increased network heterogeneity predicts increased persuasion, but when identical messages are presented in a way that invokes morality the impact of network heterogeneity disappears or even reverses marginally. This interactive effect was replicated in two very different political issues: gay adoption and nationalized healthcare. Implications for persuasion by morally motivated sources independent of the effects of specific moral arguments are discussed.  相似文献   
224.
The experiments conducted aimed to investigate whether reduced accuracy when counting stimuli presented in rapid temporal sequence in adults with dyslexia could be explained by a sensory processing deficit, a general slowing in processing speed or difficulties shifting attention between stimuli. To achieve these aims, the influence of the inter-stimulus interval (ISI), stimulus duration, and sequence length were evaluated in two experiments. In the first that used skilled readers only, significantly more errors were found with presentation of long sequences when the ISI or stimulus durations were short. Experiment 2 used a wider range of ISIs and stimulus durations. Compared to skilled readers, a group with dyslexia had reduced accuracy on two-stimulus sequences when the ISI was short, but not when the ISI was long. Although reduced accuracy was found on all short and long sequences by the group with dyslexia, when performance on two-stimulus sequences was used as an index of sensory processing efficiency and controlled, group differences were found with presentation of stimuli of short duration only. We concluded that continuous, repetitive stimulation to the same visual area can produce a capacity limitation on rapid counting tasks in all readers when the ISIs or stimulus durations are short. While reduced accuracy on rapid sequential counting tasks can be explained by a sensory processing deficit when the stimulus duration is long, slower processing speed in the group with dyslexia explains the greater inaccuracy found as sequence length is increased when the stimulus duration is short.  相似文献   
225.
Volunteers are crucial to the survival of non‐profit organisations, who therefore have a fundamental interest in sustaining voluntary engagement over time. A central variable regarding sustained voluntary engagement is volunteers' organisational commitment, which has so far been a neglected research issue. The study at hand therefore explicitly focuses on hospice volunteers' commitment. Starting from the assumption that variables at the experience stage of volunteerism may be relevant in predicting volunteer commitment, questionnaire data on volunteers' motives, motive fulfilment and role identity were collected in a sample of hospice volunteers (N = 276). Results of multiple regression analyses show positive relationships between altruistic motive fulfilment and a volunteer role identity on the one hand and volunteer commitment on the other. Observed interaction effects imply that altruistic motive fulfilment is of importance both at the initial phase of volunteering and for long‐term volunteers. Moreover, interaction effects provide evidence that the fulfilment of egoistic motives is of particular importance amongst volunteers to whom egoistic motives are central. Thus, the fulfilment of altruistic motives and facilitating the development of a volunteer role identity should be permanent concerns in building a committed workforce. Egoistic motive fulfilment in contrast is of special relevance, when egoistic motives for volunteering are strong. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
226.
Consumers often encounter goods and services that provide cues to mark their progress. We define the term “goal progress cues” to reflect the diverse category of cues that highlight progress towards a goal. Across a series of three studies, we show that entity theorists, who rely on cues that highlight completion in order to signal their abilities to others, evaluate tasks that include these cues more favorably than those that lack these features. In contrast, incremental theorists, who focus on improving competence, are impacted only by progress cues that highlight learning. We demonstrate these findings across a variety of goal pursuit contexts that represent a mix of customer-centric (retail queues), service-oriented managerial (sales calls), and personal achievement consumer product (mazes) domains using both behavioral and self-reported measures. We conclude with a discussion about the theoretical and substantive implications of our findings.  相似文献   
227.
Parental presence is often employed to alleviate distress in children within the context of surgery under general anesthesia. The critical component of this intervention may not be the presence of the parent per se, but more importantly the behaviors in which the parent and child engage when the parent is present. The purpose of the current study was to examine the sequential and reciprocal relationships between parental behaviors and child distress during induction of general anesthesia. Participants were 32 children (3–6 years) receiving dental surgery as a day surgery procedure, and their parents. A modified Child Adult Medical Procedures Interaction Scale-Revised was used to code parent and child behaviors. Initial child distress led to increased parental provision of reassurance and decreased provision of physical comfort. Our findings may inform the development of preoperative preparation programs whereby parents can be appropriately educated about what behaviors will be helpful/unhelpful for their child during induction of general anesthesia.  相似文献   
228.
We studied whether the origins of math anxiety can be related to a biologically supported framework of stress induction: (un)controllability perception, here indicated by self‐reported independent efforts in mathematics. Math anxiety was tested in 182 children (8‐ to 11‐year‐olds). Latent factor modeling was used to test hypotheses on plausible causal processes and mediations within competing models in quasi‐experimental contrasts. Uncontrollability perception in mathematics, or (in)dependence of efforts, best fit the data as an antecedent of math anxiety. In addition, the relationship of math anxiety with gender was fully mediated by adaptive perception of control (i.e. controllability). That is, young boys differ from girls in terms of their experience of control in mathematics learning. These differences influence math anxiety. Our findings are consistent with recent suggestions in clinical literature according to which uncontrollability makes women more susceptible to fear and anxiety disorders. A video abstract of this article can be viewed at http://www.youtube.com/watch?v=I4b_47Y-e_U  相似文献   
229.
Executive functions (EFs; e.g. working memory, inhibitory control) are mediated by the prefrontal cortex and associated with optimal cognitive and socio‐emotional development. This study provides the first concurrent analysis of the relative contributions of maternal EF and caregiving to child EF. A group of children and their mothers (= 62) completed age‐appropriate interaction (10, 24, 36 months) and EF tasks (child: 24, 36, and 48 months). Regression analyses revealed that by 36 months of age, maternal EF and negative caregiving behaviors accounted for unique variance in child EF, above and beyond maternal education and child verbal ability. These findings were confirmed when using an early child EF composite‐our most reliable measure of EF – and a similar pattern was found when controlling for stability in child EF. Furthermore, there was evidence that maternal EF had significant indirect effects on changes in child EF through maternal caregiving. At 24 months, EF was associated with maternal EF, but not negative caregiving behaviors. Taken together, these findings suggest that links between negative caregiving and child EF are increasingly manifested during early childhood. Although maternal EF and negative caregiving are related, they provide unique information about the development of child EF. A video abstract of this article can be viewed at http://www.youtube.com/watch?v=NPKXFbbrkps  相似文献   
230.
In the current brief report, we examined threat perception in a group of young children who may be at‐risk for anxiety due to extreme temperamental shyness. Results demonstrate specific differences in the processing of social threats: 4‐ to 7‐year‐olds in the high‐shy group demonstrated a greater bias for social threats (angry faces) than did a comparison group of low‐shy children. This pattern did not hold for non‐social threats like snakes: Both groups showed an equal bias for the detection of snakes over frogs. The results suggest that children who are tempermentally shy have a heightened sensitivity to social signs of threat early in development. These findings have implications for understanding mechanisms of early threat sensitivity that may predict later socioemotional maladjustment.  相似文献   
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