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51.
Extinction of auditory fear conditioning is thought to form a new memory. We previously found that rats with vmPFC lesions could extinguish fear to the tone within a session, but showed no recall of extinction 24 h later. One interpretation is that the vmPFC is the sole storage site of extinction memory. However, it is also possible that lesioned rats were unable to retrieve extinction memory stored in other structures. To determine if a latent extinction memory could be retrieved with additional training, we repeated the experiment but added an additional 5 d of extinction reminder trials. Replicating our previous findings, vmPFC-lesioned rats extinguished normally on day 1, but showed no recall of extinction on day 2. Over the next 5 d, however, lesioned rats showed significant savings in their rate of re-extinction. Thus, the vmPFC is not the only site where extinction memory is stored. Nevertheless, lesioned rats receiving only two extinction trials per day required twice as many days to initiate extinction as controls. Although recall of extinction is possible without the vmPFC, it is significantly delayed. We suggest that the vmPFC accelerates extinction by permitting access to recently learned extinction trials, thereby maximizing behavioral flexibility.  相似文献   
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This study examines whether the relationship between ethical leadership and organizational citizenship behaviours (OCBs) is contingent on organizational identification. Drawing on substitutes for leadership theory, the study proposes that the relationship between ethical leadership and OCBs will be attenuated when employees strongly identify with their organization. Using a sample of Egyptian banking sector employees, this proposition was tested with hierarchal linear modelling (HLM). The results revealed that the positive relationship between ethical leadership and OCBs was stronger for those lower in organizational identification than for those higher in identification. Overall, the findings of the study shed new light on the conditions through which ethical leadership enhances OCBs.  相似文献   
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In this paper, I review and compare major literature on goals in argumentation scholarship, aiming to answer the question of how to take the different goals of arguers into account when analysing and evaluating public political arguments. On the basis of the review, I suggest to differentiate between the different goals along two important distinctions: first, distinguish between goals which are intrinsic to argumentation and goals which are extrinsic to it and second distinguish between goals of the act of arguing and goals of argumentative interactions. Furthermore, I propose to analyse public political arguments as multi-purposive activity types and reconstruct the argumentative exchanges as a series of simultaneous discussions. This enables us to examine public political arguments from a perspective in which the intrinsic goals of argumentation are in principle instrumental for the achievement of the socio-political purposes of argumentation, and consequently, it makes our assessment of the argumentative quality of the argument also indicative of the quality of the socio-political processes to which the arguments contribute.  相似文献   
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Decision styles reflect the typical manner by which individuals make decisions. The purpose of this research was to develop and validate a decision style scale that addresses conceptual and psychometric problems with current measures. The resulting 10-item scale captures a broad range of the rational and intuitive styles construct domain. Results from 5 independent samples provide initial support for the dimensionality and reliability of the new scale, as demonstrated by a clear factor structure and high internal consistency. In addition, our results show evidence of convergent and discriminant validity through expected patterns of correlations across decision-making individual differences and the International Personality Item Pool (IPIP) Big Five traits. Research domains that would benefit from incorporating the concept of decision styles are discussed.  相似文献   
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The novel coronavirus disease (COVID-19) is highly contagious. More than 247 million cases have been confirmed by the end of October 2021. Seeking help earlier may slow the spread of COVID-19 because it may help in early detection of infected cases, and it facilitate tracing those who were with close contact with infected cases. The purpose of this study is to identify participants’ intentions toward COVID-19 seeking help and the factors affecting their decision. This is a cross-sectional study. An online survey using Google Forms was used for data collection. Hierarchical multiple regression analysis was used to explain intentions to seek help for COVID-19. The concepts included in the Theory of Planned Behavior and COVID-19 knowledge were used as predictors. The sample included 780 participants, with an average age of 28.60±9.86 years old. Most of the sample were female (67.4%) and having a bachelor’s degree (72.7%). Participants showed high level of knowledge regarding COVID-19, 73% of the sample had a total knowledge score equal to or higher than 85%. Also, participants had high positive attitudes and high intentions to seek help for COVID-19. The four predictors: Attitudes towards COVID-19, subjective norm, perceived behavioral control, and COVID-19 knowledge significantly explained intentions to seek help. Participants had high intentions to seek help for COVID-19, which was related to having positive attitudes toward seeking help, high social approval, high perceived controllability, and high COVID-19 knowledge levels. Regular awareness campaigns during early stages of pandemics should be performed to improve attitudes and knowledge level, which may improve prevention measures, and promote help seeking behaviors. Consequently, this may facilitate early detection of cases, and slow the spread of pandemics.  相似文献   
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This study contributes to the new and growing body of research on shared cognition by examining how individuals entering a group decision-making context with different perspectives of the issues to be discussed arrive at cognitive consensus. Cognitive consensus refers to similarity among group members regarding how key matters are conceptualized and was operationalized as shared assumptions underlying decision issues in the present research. Utilizing 37 student groups participating in a multi-issue decision-making exercise, the study investigated antecedents and correlates of cognitive consensus. Results revealed that unanimity decision rule groups achieved more cognitive consensus than majority rule groups. In addition, group members inquiring concerning the reasons underlying others' decision preferences, accepting others' viewpoints as legitimate, and incorporating others' perspectives into their own interpretations of the issues was positively related to arriving at a greater degree of cognitive consensus. Cognitive consensus also positively influenced expectations regarding decision implementation and satisfaction.  相似文献   
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The NMDA receptor (NMDAR) subunit GluN1 is an obligatory component of NMDARs without a known functional homolog and is expressed in almost every neuronal cell type. The NMDAR system is a coincidence detector with critical roles in spatial learning and synaptic plasticity. Its coincidence detection property is crucial for the induction of hippocampal long-term potentiation (LTP). We have generated a mutant mouse model expressing a hypomorph of the Grin1N598R allele, which leads to a minority (about 10%) of coincidence detection-impaired NMDARs. Surprisingly, these animals revealed specific functional changes in the dentate gyrus (DG) of the hippocampal formation. Early LTP was expressed normally in area CA1 in vivo, but was completely suppressed at perforant path-granule cell synapses in the DG. In addition, there was a pronounced reduction in the amplitude of the evoked population spike in the DG. These specific changes were accompanied by behavioral impairments in spatial recognition, spatial learning, reversal learning, and retention. Our data show that minor changes in GluN1-dependent NMDAR physiology can cause dramatic consequences in synaptic signaling in a subregion-specific fashion despite the nonredundant nature of the GluN1 gene and its global expression.According to Hebb''s postulate, neurons require a molecular mechanism to detect synchronous activity in order to change the strength of synaptic connectivity (Hebb 1949). NMDA receptors (NMDARs) are molecular coincidence detectors, and selective NMDAR antagonists block the induction of long-term potentiation (LTP) in both the dentate gyrus (DG) and CA1 regions of the hippocampus (Bliss and Collingridge 1993; Martin et al. 2000). NMDARs have been long known for their role in spatial learning, but more recently have been implicated in other forms of cognitive function and dysfunction (Gruart et al. 2006; Whitlock et al. 2006; Castner and Williams 2007; Kristiansen et al. 2007; Wilson and Linster 2008).Neuronal NMDARs are hetero-tetrameric ligand-gated ion channels typically comprised of two types of subunits. Two copies of the mandatory GluN1 subunit (or NR1 subunit [Collingridge et al. 2009] encoded by Grin1) are associated with two copies from the GluN2 family, GluN2A–D (or NR2A–D). The GluN1 subunit is expressed ubiquitously both spatially and temporally throughout the developing and adult brain. Global knockout mice models of the GluN1 subunit are postnatally lethal within hours after birth (Forrest et al. 1994; Li et al. 1994), and cell-specific GluN1 mice knockouts (Tsien et al. 1996; Nakazawa et al. 2002; McHugh et al. 2007; Niewoehner et al. 2007) have provided insights on how specific synapses and regional neuronal networks are dependent on NMDAR function.The early postnatal lethality of the global GluN1 knockout is in contrast to the null mutants of the four AMPA receptor genes and other major synaptic proteins, such as αCaMKII (Silva et al. 1992a,b; Jia et al. 1996; Zamanillo et al. 1999; Meng et al. 2003). This can be at least partially explained by the absence of any close GluN1 homologs, which could functionally compensate for the absence of the GluN1 subunit. Recombinant expression studies defined the GluN1 subunit as a mandatory component of NMDARs. This constellation provides a specific opportunity to test whether different local neuronal subnetworks are affected differentially by mutant Grin1 alleles associated with subtle alterations of the functional properties of NMDARs.GluN1 subunits with the N598R point mutation (GluN1R) yield functional NMDARs that are Mg2+ insensitive and Ca2+ impermeable (Burnashev et al. 1992; Mori et al. 1992). The Grin1N598R allele that codes for GluN1R subunits is a gain-of-function mutation that is dominant lethal, even in heterozygous and hemizygous lines (Single et al. 2000; Rudhard et al. 2003). NMDARs with GluN1R subunits do not act as coincidence detectors and, interestingly, mice expressing exclusively the GluN1R allele lack whisker-related pattern formation in the neonate brainstem (Rudhard et al. 2003).To investigate the functional importance of GluN1 subunits with the N598R point mutation, we took advantage of the generation of a variant mutant line of mice (GluN1Rneo/+) expressing a minority (around 10%) of these mutant NMDARs. Even though the majority of the NMDARs are normal, all neurons expressing NMDARs will contain a subset of receptors carrying this mutation.Therefore, this mouse model is an ideal candidate to study the impact of subtle alterations of NMDAR function on different neuronal networks, such as those comprising the hippocampal formation.Studies examining region-specific targeted disruption of GluN1 expression in subregions of the hippocampus have revealed subtle yet important contributions of this NMDAR subunit in synaptic plasticity and spatial learning and memory. CA1-restricted knockout of GluN1 expression in the hippocampus caused impaired spatial learning and memory as well as reduced CA1-LTP (Tsien et al. 1996). In the case of the disruption of GluN1 expression in the DG region of the hippocampus, more subtle behavioral impairments were apparent, including the inability to discriminate between two similar contexts (pattern separation) and deficits in spatial working memory despite normal LTP in the CA1 region (McHugh et al. 2007; Niewoehner et al. 2007).Our GluN1Rneo/+ mice differ from the region-specific GluN1 mutant mice in that they express the mutant hypomorph at the same level in different subregions of the hippocampus. Interestingly, we found that this allele leads to substantial differences in short- and long-term plasticity between area CA1 and the DG of the hippocampus. The specific impairment in the DG was accompanied by impaired spatial recognition, spatial learning, reversal learning, and retention. Our data establish the possibility of a circuit-specific phenotype caused by a mutant variant of a globally expressed major nonredundant synaptic protein.  相似文献   
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