Mechanisms of blocking by contextual stimuli

The influence of contextual stimuli on the conditioning and performance of responding to a discrete stimulus was examined in the US preexposure paradigm using both context shift manipulations and a measure of context conditioning. Four groups of rats received both repeated exposure to an electric shock US in one context (Context 1), and repeated nonshocked exposure to a second context (Context 2). Two additional groups of rats received exposure to these contexts, but never received shock presentations. Rats exposed to shock learned to escape from the stimuli of Context 1, but did not escape from the stimuli provided by Context 2. Rats not exposed to shock failed to escape from either context. All rats then received a single CER conditioning session in which four pairings of a 3-min noise CS and shock US were presented. Half the rats received those CS-US pairings in the excitatory Context 1, while the remaining rats received those pairings in the neutral Context 2. Finally, half the rats in each of the CER conditioning treatments received extinction test trials of the noise CS in Context 1, while the remaining rats received those test trials in Context 2. Thus, this design factorially manipulated the presence of excitatory or neutral contextual stimuli during both conditioning and testing of a discrete CS. In comparison with the two groups of rats never preexposed to shock alone, attenuation in acquisition of conditioned suppression observed during test trials occurred only when CER conditioning had been administered in the excitatory Context 1, and this effect was manifested when testing occurred in either the excitatory Context 1 or the neutral Context 2. These results support the model of R. A. Rescorla and A. R. Wagner (1972) (in A. H. Black & W. F. Prokasy (Eds.) Classical Conditioning II, pp. 64–99, New York: Appleton-Century-Crofts) which asserts that contextual stimuli and sicrete CSs compete for limited associative strength supportable by a given US.     

The influence of flavor preexposure and test interval on conditioned taste aversions in the rat

The effects of flavor preexposure and test interval on conditioned taste aversions were examined in four experiments. In the first three experiments, prior experience with a flavor different from that used as a conditioned-stimulus (CS) produced attenuated aversions when testing occurred after a 1-day interval but not after a 21-day interval. Preexposure to the same stimulus used as a CS produced attenuated aversions at both 1- and 21-day intervals. In Experiment 4, a delay interval between flavor preexposure and conditioning eliminated the attenuating effect of preexposure, but only when different stimuli were used for preexposure and conditioning. These data could not be easily accounted for by contemporary interpretations of preexposure as an event that interferes with subsequent acquisition of a conditioned aversion. An alternative retrieval interference hypothesis was outlined.     

Feedback during exposure to inescapable shocks and subsequent shock-escape performance

In two experiments, we assessed the ability of a feedback stimulus during helplessness training to reduce the performance deficits common to inescapable shock. In each experiment, four groups of rats were exposed to either escapable shock (E), inescapable shock with a feedback stimulus following shock termination (Y-FS), inescapable shock with no feedback stimulus (Y-NFS), or no shock (N). The feedback stimulus eliminated the interference effects of inescapable shock when tested with an FR-3 lever press escape task (Experiment 1) or on an FR-1 task with a 3-s delay between the response and shock termination (Experiment 2). These results suggest that stress-induced biochemical changes may mediate the interference effects seen in inescapably shocked rats.     

Investigations of the reinstatement of extinguished fear

In two experiments, fear was conditioned to the situational cues in one compartment of a hurdle-jumping apparatus and was then extinguished. Subsequently, either one shock (Experiment 1) or three or nine shocks (Experiment 2) were given in a situation distinctively different from that in which conditioning and extinction had taken place. Although some associative strength between the situational cues and fear was shown to have remained after extinction, in neither experiment did the postextinction-shock treatment increase the fear elicited by these cues: Escape-from-fear performance was no better in the shocked groups than in control groups given no additional shock. Thus, the nonassociative hypothesis which postulates that inflating the value of the representation of the UCS with shock-alone presentations can reinstate the extinguished fear of a stimulus was not supported. Rather, the results showed that, after extinction, an increase in fear of a simulus depended on further conditioning to that stimulus. The data also indicated that the nonvisual components of the situational cues predominated over the visual component.     

Variations in explicitly unpaired training are differentially effective in producing conditioned inhibition

To evaluate a contingency interpretation of conditioned inhibition (CI), rats were given “explicity unpaired” training in which the locus and duration of a CS within the inter-US (shock) interval were systematically manipulated for different groups. Summation and retardation tests in Experiment 1 indicated that stronger CI resulted from both a backward and a trace CS than from a midlocus CS of equal or greater duration. Complementing these findings, the same tests in Experiment 2 showed that, by comparison with novel-stimulus controls, CI developed to a trace CS but not to a mid-locus CS, nor to a trace CS that was accompanied by an immediate signal for the US. These findings argue against a contingency interpretation of CI and favor a contiguity interpretation stressing the short-term rehearsal of stimulus events. Such rehearsal of the US allows a backward CS, but not a mid-locus CS with an extended US-CS interval, to be discriminated as a signal for nonreinforcement, and thus to develop as a conditioned inhibitor. Similarly, excitatory conditioning to the memory trace of a CS allows the nominal trace CS to develop as a signal for nonreinforcement, and thus as a conditioned inhibitor, but not when its memory trace is overshadowed by another CS that immediately precedes the US. In short, the development of CI is facilitated when excitation is mediated by the memorial processing of either the US or a discrete CS for the US rather than by contextual cues.     

Human Agency in the Missio Dei and the Problem of Discipleship

At the heart of this article is an inquiry into the relationship between human and divine agency in the doctrine of the missio Dei and a critique of the turn to the language of discipleship in looking to articulate this agency. Taking the World Council of Churches’ Commission of World Mission and Evangelism's two recent documents, Together towards Life: Mission and Evangelism in Changing Landscapes (TTL) and the “Arusha Call to Discipleship,” as a case study, this article will seek to articulate an account of human participation in the missio Dei which maintains the emphasis on spirituality in TTL. Through a close reading of TTL and the Arusha Call, the article will demonstrate that the introduction of discipleship language has not solved the issue of agency but rather has changed the account of agency and, as a result, the missiology. By turning to accounts of faithful participation from qualitative research into British Methodism, to John V. Taylor's Go-between God, and to Pope Francis’ Evangelii gaudium, I will suggest that a better account of human agency in the missio Dei can be developed by emphasizing the pneumatology of TTL and by turning to language of attentiveness, accompaniment, and discernment.     

Le médecin expert confronté aux confidences de la personne expertisée

During an expertise, if the expert “discovers” or is entrusted with information concerning an offence, should he report it to the authorities? Could the expert be sanctioned in the absence of denunciation of a tort or criminal act? The answer will be nuanced on a case-by-case basis. The expert confronted with the revelation of a crime or misdemeanor must decide in good conscience what he reveals in his report, or even report it to the prosecution.     

Ordinance influences individuals' perceptions towards prospects of social circumstance but not the status quo: An experimental field study on sexual minorities issues in Japan

Scientific evidence shows that institutional decisions can change individuals' private attitudes towards relevant issues. However, little is known about their effect on individuals' perceptions of social norms. This intriguing question has gained the attention of scholars. Nonetheless, the findings are primarily observed only in samples of the Western, Educated, Industrialised, Rich, and Democratic countries, leading to doubts about their generalisability. This study experimentally tested residents' (N = 411) reactions to the new Tokyo ordinance prohibiting discrimination against sexual minorities enacted on October 5, 2018, and tested whether it dispelled self–other discrepancies regarding tolerance towards sexual minorities (i.e., pluralistic ignorance). The results showed that exposure to information about enactment increased future perceptions of support and understanding of sexual minorities. By contrast, private attitudes, perceptions of current social norms, and willingness to speak out did not change. Willingness to speak out was indirectly enhanced through increased perceptions of gaining future support. Furthermore, Tokyo residents overestimated other residents' negative attitudes towards sexual minorities. However, even when informed of the new ordinance, this self–other discrepancy in intolerance towards sexual minorities was not corrected. These findings suggest that institutional decisions can shape the perception of social norm change in the future beyond Western countries.     

亲子依恋与儿童抑郁症状的关系：儿童对环境的生物敏感性的作用及父母差异

不良的亲子依恋是导致儿童抑郁症状的风险因素,但其对儿童的影响会因儿童对环境的生物敏感性不同而存在差异。为探究家庭中母子、父子依恋对儿童抑郁症状的影响及儿童生物敏感性(本文中采用迷走神经抑制作为指标)在其中的作用,本研究结合行为任务、问卷报告、生理测量等多种研究手段,招募150名学龄儿童(平均年龄8.64岁,63名女孩)参与研究。结果表明：(1)学龄儿童的母子依恋水平高于父子依恋水平。(2)高水平的母子依恋与父子依恋会同等程度地降低儿童的抑郁症状。(3)儿童对环境的生物敏感性对母子依恋影响儿童抑郁症状路径的调节作用显著,生理上对环境更敏感(高迷走神经抑制)的儿童更易得益于高母子依恋,表现出较低的抑郁水平;但同时,这类儿童在母子依恋较低时也更易表现出较高的抑郁水平。(4)儿童的生物敏感性对父子依恋影响儿童抑郁症状路径的调节作用不显著,高父子依恋对生物敏感性水平不同的儿童均存在有利影响。(5)在不同情境中测量的迷走神经抑制对亲子依恋影响儿童抑郁症状的调节作用模式相似,表现出跨情境一致的特点。本研究率先揭示儿童迷走神经抑制与亲子依恋对儿童抑郁症状的联合作用机制及父母角色差异。