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991.
Emerging evidence suggests that nicotine may enhance short‐term memory. Some of this evidence comes from nonhuman primate research using a procedure called delayed matching‐to‐sample, wherein the monkey is trained to select a comparison stimulus that matches some physical property of a previously presented sample stimulus. Delays between sample stimulus offset and comparison stimuli onset are manipulated and accuracy is measured. The present research attempted to systematically replicate these enhancement effects with pigeons. In addition, the effects of nicotine were assessed under another, more dynamic, memory task called titrating‐delay matching‐to‐sample. In this procedure, the delay between sample offset and comparison onset adjusts as a function of the subject's performance. Correct matches increase the delay, mismatches decrease the delay, and titrated delay values serve as the primary dependent measure. Both studies examined nicotine's effects under acute and chronic administration. Neither provided clear or compelling evidence of memory enhancement following nicotine administration despite reliable and systematic dose‐related changes in response latency measures. A modest dose‐related effect on accuracy was found, but the magnitude of the effect appears to be directly related to tactics of data analysis involving best‐dose analyses of a very circumscribed subset of trial types.  相似文献   
992.
Thirty college students attempted to form three 3-node 5-member equivalence classes under the simultaneous protocol. After concurrent training of AB, BC, CD, and DE relations, all probes used to assess the emergence of symmetrical, transitive, and equivalence relations were presented for two test blocks. When the A-E stimuli were all abstract shapes, none of 10 participants formed classes. When the A, B, D, and E stimuli were abstract shapes and the C stimuli were meaningful pictures, 8 of 10 participants formed classes. This high yield may reflect the expansion of existing classes that consist of the associates of the meaningful stimuli, rather than the formation of the ABCDE classes, per se. When the A-E stimuli were abstract shapes and the C stimuli became S(D)s prior to class formation, 5 out of 10 participants formed classes. Thus, the discriminative functions served by the meaningful stimuli can account for some of the enhancement of class formation produced by the inclusion of a meaningful stimulus as a class member. A sorting task, which provided a secondary measure of class formation, indicated the formation of all three classes when the emergent relations probes indicated the same outcome. In contrast, the sorting test indicated "partial" class formation when the emergent relations test indicated no class formation. Finally, the effects of nodal distance on the relatedness of stimuli in the equivalence classes were not influenced by the functions served by the C stimuli in the equivalence classes.  相似文献   
993.
Domestic hens responded under multiple fixed‐ratio fixed‐ratio schedules with equal fixed ratios. One component provided immediate reinforcement and the other provided reinforcement after a delay, signaled by the offset of the key light. The components were presented quasirandomly so that all four possible transitions occurred in each session. The delay was varied over 0, 4, 8, 16, and 32 s with fixed‐ratio 5 schedules, and over 0, 8 and 32 s with fixed‐ratio 1, 15 and 40 schedules. Main effects of fixed‐ratio value and delay duration were detected on between‐ratio pauses. Pauses were longer when the multiple‐schedule stimulus correlated with a delayed‐reinforcer component was presented, with the longest pauses occurring at the transition from a component with an immediate reinforcer to one with a delayed reinforcer. Pause durations were shortest during immediate components. Overall, both the presence or absence of a delay in the upcoming component, and the presence or absence of a delay in the preceding component affected pause length, but the upcoming delay had the larger effect. Thus changes in delay had similar effects to past reports of the effects of changes in response force, response requirement, and reinforcer magnitude in multiple fixed‐ratio fixed‐ratio schedules.  相似文献   
994.
Competing models of attention make different predictions of how priming from recent stimulus processing could interact with intended selection. The present experiment examined the interaction between exogenous attention and endogenous priming across trial sequences. A sound cue directed attention to left, right or both sides before a dichotic syllable pair was presented. Participants were asked to report one syllable from each trial. Results showed that responses were slower on trials where one of the presented syllables had also been presented on the previous trial. Within these trials, the repeated syllable was selected less frequently, and the responses doing so were slower. Examined according to response choice on the preceding trial, syllables that had been ignored on the preceding trial tended to be ignored on the current trial (negative priming), while syllables that had been selected on the preceding trial tended to be selected on the current trial (positive priming). Responses that followed these selection biases were faster than responses that did not. Response selection was also influenced by the attention direction cue for the current trial, but not by the cue presented on the preceding trial. The results support an attentional model where traces from the preceding processing are retained, and current selection is biased to minimize cognitive conflict between recent and current processing. Negative priming appears to be due to after-effects of preceding processing, independently of the intentions behind that processing. The study accounts for positive and negative priming of dichotic listening sequences within an established, computationally viable biased competition framework.  相似文献   
995.
Bringing evidence based programs to scale was a major initial impetus for the development of the Interactive Systems Framework for Dissemination and Implementation (ISF). The ISF demonstrates the importance of the Support System in facilitating the uptake of innovations in the community (the Delivery System). Two strategies that members of the Support System commonly use are training‐of‐trainers (TOT) models and technical assistance (TA). In this article, we focus on the role of the Support System in bringing evidence‐based programs (EBPs) to scale in the Delivery System using a case example, with special attention on two strategies employed by Support Systems—trainingoftrainers (TOT) and proactive technical assistance. We then report on findings from a case example from the Promoting Science Based Approaches to Teen Pregnancy Prevention project that furthers our conceptualization of these strategies and the evidence base for them. We also report on the limitations in the literature regarding research on TOTs and proactive TA and provide suggestions for future research on TOTs and proactive TA that will enhance the science and practice of support in the ISF. Special Issue: Advances in Bridging Research and Practice Using the Interactive System Framework for Dissemination and Implementation; Guest Editors: Abraham Wandersman, Paul Flaspohler, Catherine A. Lesesne, Richard Puddy; Action Editor: Emilie Phillips Smith  相似文献   
996.
Individual differences in attachment are well established as a correlate of couple relationship satisfaction. However, less is known about the role of attachment in predicting satisfaction at specific milestone points in couple relationships. The present study explored the role of attachment in predicting relationship satisfaction during couples’ first pregnancy, and the mediating role of relationship enhancing behaviors. Male and female attachment anxiety and avoidance predicted their own low relationship satisfaction, and this was partially mediated by relationship enhancing behaviors. Male attachment anxiety and avoidance predicted low female satisfaction, and this was fully mediated by relationship enhancing behaviors. This study is the first to highlight the important role of male attachment during pregnancy, and the mediating role of relationship enhancing behaviors.  相似文献   
997.
Previous research has consistently shown that individuals with delusions typically exhibit a jumping‐to‐conclusions (JTC) bias when administrated the probabilistic reasoning ‘beads task’ (i.e., decisions made on limited evidence and/or decisions over‐adjusted in light of disconfirming evidence). However, recent work in this area has indicated that a lack of comprehension of the task may be confounding this finding. The purpose of the present study was to evaluate the influence of task administration, delusion‐proneness, and miscomprehension on the elucidation of the JTC bias. A total of 92 undergraduate university students were divided into one of two task conditions (i.e., non‐computerised and computerised) and were further identified as either delusion‐prone or non‐delusion‐prone and as comprehending or non‐comprehending the task. Overall, 25% of the sample demonstrated a JTC bias, and just over half made illogical responses consistent with a failure to comprehend the task. Qualitative evidence of comprehension revealed that these ‘illogical responses’ were being driven by a misunderstanding of task instructions. The way the task was administrated and levels of delusion‐proneness did not significantly influence JTC. However, miscomprehending participants were significantly more likely to exhibit the bias than those who did comprehend. These results suggest that miscomprehension rather than delusion‐proneness may be driving the JTC bias, and that future research should include measures of miscomprehension.  相似文献   
998.
Abstract : In this article I argue that the Lutheran doctrine of two kingdoms provides a good basis for the legitimate participation of all citizens in political discourse and decisions, no matter what faith they hold. The argument is backed by selected insights from philosopher Jürgen Habermas and sociologists Linda Woodhead and Paul Heelas. Against this backdrop, I suggest some challenges for a theology that addresses issues related to religion and society.  相似文献   
999.
The aim of this research was to investigate the feasibility of achieving Improving Access to Psychological Therapies (IAPT) for people from Black, Asian and Minority Ethnic (BAME) communities living in the UK, with specific reference to Bengali, Urdu, Tamil and Somali speaking communities. Focus groups were carried out with each of the communities to investigate how they conceptualise and experience ‘mental health issues’ and what they do when faced with what they regard as these issues. A thematic analysis of the data suggested that participants did not fully understand common conceptualisations about mental health issues, nor did they know how to seek mental health support. Implications of cultural barriers and recommendations for IAPT outcomes for the four communities are discussed.  相似文献   
1000.
Previous research has shown that rats can learn matching-to-sample relations with olfactory stimuli; however, the specific characteristics of this relational control are unclear. In Experiment 1, 6 rats were trained to either match or nonmatch to sample in a modified operant chamber using common household spices as olfactory stimuli. After matching or nonmatching training with 10 exemplars, the contingencies were reversed with five new stimuli such that subjects trained on matching were shifted to nonmatching and vice versa. Following these reversed contingencies, the effects of the original training persisted for many trials with new exemplars. In Experiment 2, 9 rats were trained with matching procedures in an arena that provided for 18 different spatial locations for comparison stimuli. Five subjects were trained with differential reinforcement outcomes and 4 with only one type of reinforcer. Differential outcomes and multiple exemplars facilitated learning, and there was strong evidence for generalization to new stimuli for most rats that acquired several conditional discriminations. Performances with novel samples were generally above chance, but rarely reached the high levels obtained during baseline with well-trained stimulus relations. However, taken together, the data from the two experiments extend previous work, show that rats can learn both match and nonmatch relations with different experimental protocols, and demonstrate generalization to novel sample stimuli.  相似文献   
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