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131.
Three experiments with rats examined the possibility that the cue-consequence specificity effect is not mediated by the conditioning of selective associations, but instead reflects the selective behavioral expression of taste-illness and exteroceptive-shock conditioning. Experiment 1 showed that the selective aversion performance could be obtained despite the use of locomotor withdrawal from the CS as the index of conditioning. Experiment 2 compared the response profiles of animals conditioned with footshock or illness to presentation of a saccharin or noise CS. During the test with the noise CS, lithium-conditioned subjects did not differ from control rats on any of several behavioral categories, but shock-conditioned rats showed high levels of freezing in response to the noise cue. During the saccharin test, lithium-treated rats engaged in behaviors such as chin wiping, head shaking, and gaping; these behaviors were rarely or never seen in shock-conditioned rats or controls, whose behavioral profiles during the saccharin test were almost identical. Experiment 3, using a blocking design, found that a noise-lithium pairing did not attenuate subsequent conditioning of a saline-lithium association, nor did a saccharin-shock pairing interfere with conditioning of a noise-shock association. These results confirm that the cue-consequence specificity effect is mediated by the selective associability of taste with illness and of exteroceptive cues with footshock.  相似文献   
132.
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.  相似文献   
133.
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.  相似文献   
134.
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.  相似文献   
135.
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.  相似文献   
136.
American Indian/Alaska Native (AI/AN) communities are disproportionally impacted by the opioid overdose epidemic. There remains a dearth of research evaluating methods for effectively implementing treatments for opioid use disorder (OUD) within these communities. We describe proceedings from a 2-day Collaborative Board (CB) meeting tasked with developing an implementation intervention for AI/AN clinical programs to improve the delivery of medications to treat OUD (MOUD). The CB was comprised of Elders, cultural leaders, providers, individuals with lived experience with OUD, and researchers from over 25 communities, organizations, and academic institutions. Conversations were audio-recorded, transcribed, and coded by two academic researchers with interpretation oversight provided by the CB. These proceedings provided a foundation for ongoing CB work and a frame for developing the program-level implementation intervention using a strength-based and holistic model of OUD recovery and wellbeing. Topics of discussion posed to the CB included engagement and recovery strategies, integration of extended family traditions, and addressing stigma and building trust with providers and clients. Integration of traditional healing practices, ceremonies, and other cultural practices was recommended. The importance of centering AI/AN culture and involving family were highlighted as priorities for the intervention.  相似文献   
137.
Research demonstrates that contingent and appropriate maternal responsiveness to infant requests and bids for attention leads to better language outcomes. Research also indicates that infants who are less distracted by irrelevant competing stimulation and attend efficiently to audiovisual social events (e.g., faces and voices) show better language outcomes. However, few studies have assessed relations between maternal responsiveness, infant attention to faces and voices, and distractibility, and how together these factors lead to early language outcomes. A newly developed audiovisual protocol, the Multisensory Attention Assessment Protocol (MAAP; Bahrick et al., 2018), allows researchers to examine individual differences in attention to faces and voices and distractibility, and to assess relations with other variables. At 12 months, infants (n = 79) in an ongoing longitudinal study participated in the MAAP to assess intersensory matching of synchronous faces and voices and attention to an irrelevant competing visual distractor event. They also were observed in a brief play interaction to assess infant bids for attention and maternal responsiveness (accept, redirect, or ignore). At 18 months, receptive and expressive language were assessed using the Mullen Scales of Early Learning. Several noteworthy findings emerged: 1) mothers were generally responsive, accepting 74% and redirecting 14% of infant bids, 2) infants who had a greater number of their bids redirected by mothers, and who had better intersensory matching of synchronous faces and voices, showed less attention to the distractor, and 3) infants who showed less attention to the distractor had better receptive language. Findings demonstrate that maternal redirecting of infant attention by mothers who are generally responsive may promote better infant attentional control (lower distractibility) which in turn predicts better receptive language in toddlers.  相似文献   
138.
Lowering the voting age from 18 to 16 years has recently been a hot topic of the political debate in many democratic countries. This study investigated whether the voting quality of 16–17-year-olds is inferior to that of the voting population. Shortly before the 2021 German federal election, two samples, representative for age and gender, indicated personal preferences about various political issues and weighted them according to importance, allowing for the calculation of individual expected values for political parties. Participants then indicated their voting choice. These choices were normatively correct when individuals voted for the party that best reflected their preferences, that is, the one maximizing the expected value. Results show that the voting decisions of 16–17-year-olds were as good as those by eligible voters. The study indicates that the exclusion of 16–17-year-old Germans in democratic elections cannot be justified by their lack of decision-making ability.  相似文献   
139.
注意缺陷多动障碍(attentiondeficit/hyperactivitydisorder,ADHD)行为控制不足与决策冲动密切相关,后者受内侧前额皮层(medial prefrontal cortex, mPFC)与伏隔核(nucleus accumbens, NAc)调节。为调查ADHD决策冲动与m PFC-NAc间功能耦合的关系,研究采用ADHD模型SHR (spontaneously hypertensive rat, SHR)大鼠,结合延迟折扣任务和在体电生理,研究发现,与对照Wistar (WIS)大鼠相比, SHR大鼠对延迟大奖赏的选择百分比降低; WIS大鼠m PFC-NAc的Theta频段相干值表现为延迟选择时显著大于立即选择时、首次选择时大于连续选择时、转换试次时大于连续试次时,而SHR大鼠在上述条件均低于WIS大鼠。回归分析发现m PFC-NAc的相干差值与延迟大奖赏选择率显著正相关。结果表明m PFC-NAc间功能联系减弱是ADHD决策冲动缺陷的重要环路基础,该缺陷与其深度信息加工以及策略转换能力受损有关,扩展了ADHD决策冲动的认知和神经机制的认识。  相似文献   
140.
IntroductionThe way we interact with our environment depends on our spontaneous tendency to approach or to avoid emotional experiences triggered by that environment. This dimension of the emotional experience is called the need for affect, that is, the tendency of individuals to adopt approaching or avoidance behaviour with regard to emotional stimuli.MethodsThe Need For Affect (NFA) Scale has been the subject of numerous studies since the validation of the original version (Maio & Esses, 2001) and its short version (Appel et al., 2012). However, no validation of the latter scale has been conducted in French. We propose a French version of the short NFA scale on a student sample and a sample from the general population.ResultsWe found the structure of the original scale in a French translation (of the English version). In addition, invariance tests showed that this structure remained the same for both samples.ConclusionWe recommend the use of this version of the short NFA scale for studies conducted on French-speaking samples.  相似文献   
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