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931.
Male NMRI mice were given intravenous injections of the noradrenergic neurotoxin DSP4 or the vehicle 24 to 72 h prior behavioral testing. Animals were given 2 days of training on a one-way active avoidance task. Naloxone was given in one of three doses prior to training on Day 1 and Day 2 or prior to training on Day 1 only (saline was given prior to training on Day 2). There was a dose-dependent impairment of acquisition by naloxone in the vehicle-pretreated groups; 10 mg/kg naloxone produced a significant impairment of acquisition. Naloxone also modulated retention (Day 2) performance of the active avoidance task. For vehicle-pretreated mice, 1 mg/kg naloxone facilitated and 10 mg/kg naloxone-impaired performance on Day 2. DSP4 alone produced an impairment of acquisition of this task but had no effect on retention; Day 2 scores were slightly higher in the DSP4-pretreated group than in the vehicle-pretreated group. Naloxone produced somewhat different effects in DSP4-pretreated animals than in vehicle-pretreated animals. Naloxone (1 mg/kg) ameliorated the DSP4-induced impairment of acquisition; 10 mg/kg naloxone did not significantly alter the acquisition performance of this group. For the DSP4-pretreated mice that received naloxone before training on both days, the dose-response characteristics for retention scores were similar to those of vehicle-pretreated mice; 1 mg/kg naloxone was the facilitatory dose. However, for DSP4-treated mice that received naloxone before training on Day 1 only, there was a shift to the right in the effective facilitatory dose of naloxone. For these animals, 10 mg/kg naloxone but not 1 mg/kg naloxone significantly enhanced retention performance. We discuss these results in the context of a possible state-dependent modulation by naloxone in the DSP4-treated animals.  相似文献   
932.
The role of conspecific chemical cues in the activation of sexual behavior was investigated in the female musk shrew (Suncus murinus). In Experiment 1, virgin female musk shrews were exposed to either clean cages or cages recently vacated by an adult male. Regardless of whether the male used for the sexual behavior test was "familiar" to the female (having spent the 24 h exposure in his vacant cage) or "unfamiliar," females exposed to male-related cues received mounts from males significantly sooner than females exposed to clean cages. In Experiment 2, females housed for 24 h in a cage soiled by an adult male allowed males to mount significantly sooner than females housed in a cage soiled by a castrated male, another female, or a clean cage. These results demonstrate that chemical cues, produced exclusively by adult males, promote sexual receptivity in female musk shrews.  相似文献   
933.
A recent study of the development of nonassociative learning in the siphon withdrawal reflex of Aplysia showed that dishabituation (facilitation of an habituated response) and sensitization (facilitation of a nonhabituated response) emerge according to different developmental timetables: dishabituation precedes sensitization by approximately 60 days (Rankin & Carew, 1988). Both forms of facilitation of the reflex were observed within 90 s of an electrical shock to the tail. However, more recent work by Marcus and colleagues (1988) in adult animals revealed that sensitization can have a delayed onset of 20-30 min after a strong tail shock. Since the developmental study of Rankin and Carew (1988) only tested the reflex for 10 min after tail shock, it is possible that sensitization was in fact present at earlier developmental stages, but was undetected. To examine this question, in the present study we utilized a longer (40-50 min) post-shock observation period to determine whether delayed-onset sensitization is exhibited in juvenile Aplysia, and if so, when it is expressed during development. In our first experiment, we found that Early Stage 12 juveniles (80-95 days after metamorphosis) showed significant delayed-onset sensitization 30-50 min after a strong tail shock. In a second experiment, we found that delayed-onset sensitization was absent in Stage 11 animals (20-70 days after metamorphosis). Thus delayed-onset sensitization emerges in Early Stage 12. The fact that the birthdate of delayed-onset sensitization is at least 30 days after that of dishabituation (Rankin & Carew, 1987, 1988) supports the hypothesis that these two forms of nonassociative learning may have at least partly different underlying mechanisms.  相似文献   
934.
Lee  Karisa Y.  Reis  Harry T.  Rogge  Ronald D. 《Sex roles》2020,83(11-12):685-705
Sex Roles - Essentialism, or the belief that certain categories have fundamental, intrinsic, and stable essences, pervasively influences social judgments. Among the many groupings that describe...  相似文献   
935.
Individuals who perpetrate violence may likely perceive violence as appealing and infliction of violence to derive pleasure is termed as appetitive aggression. Individuals who were abducted as children into an armed group often experience a higher number of traumatic event types, that is traumatic load and are usually socialized in a violence-endorsing environment. This study aims to investigate the interaction between age at initial abduction with that of traumatic load, and their influence on appetitive aggression along with perpetration of violent acts by former members of an armed rebel group of both sexes. Semi-structured interviews were conducted among a target group of formerly abducted rebel-war survivors (including participants with and without combat experience) from Northern Uganda. Participants included 596 women and 570 men with N = 1,166 (Mage = 32.58, SDage = 9.76, range: 18–80 years). We conducted robust linear regression models to investigate the influence of age at initial abduction, traumatic load, combat experience, and biological sex on appetitive aggression as well as their perpetrated violent acts. Our study shows, appetitive aggression and the number of perpetrated violent acts were specifically increased in individuals who were abducted young, experienced several traumatic events in their lifetime, and with previous combat experience. For perpetrated violence men showed increased levels whereas for appetitive aggression the association was independent of biological sex. Therefore, early abducted individuals with a higher traumatic load, who have combat experience, need to be given special intervention to prevent any further violence.  相似文献   
936.
Research on public opinion towards affirmative action shows that citizens often support the principle of equality while simultaneously rejecting policies that promote it in a pattern described as the “principle-policy puzzle.” The scholarship also shows that ideology and prejudice towards the targeted group explain the puzzle with respect to racial affirmative action. In this article, we use unique survey questions included in the 2014 round of the AmericasBarometer in Brazil to show that citizens tend to support electoral gender quotas while rejecting gender-based egalitarianism in a reversed version of the “principle-policy puzzle.” We argue that a different type of gender attitudes, namely benevolent sexism, shapes support for gender quotas as well as for the principle of equality. While benevolent sexists tend to reject gender equality based on views about gender complementarity and stereotypes about women's purity, they also support quotas as policies to foster such values. Our findings suggest that even though the political and scholarly debates can provide sound normative reasons for the adoption of quotas across different contexts, public support for them often relies on paternalistic views and expectations about the role of women in politics.  相似文献   
937.
The editors of the JRE solicited short essays on the COVID-19 pandemic from a group of scholars of religious ethics that reflected on how the field might help them make sense of the complex religious, cultural, ethical, and political implications of the pandemic, and on how the pandemic might shape the future of religious ethics.  相似文献   
938.
According to the cue–belief model, we assess confidence in our memories using self-credibility cues that reflect beliefs about our memory faculties. We tested the influence of meta-memory feedback on self-credibility cues in the context of eyewitness testimony, when feedback was provided prior to “testifying” via a memory questionnaire (Experiment 1) and after an initial memory questionnaire but before participants had to retake it (Experiment 2). Participants received feedback (good score, bad score, or none) on a fictitious scale purported to predict eyewitness memory ability. Those given good score feedback before testifying were more confident (but no more accurate) than those given bad score feedback. Feedback also affected confidence (good increased and bad decreased) and accuracy (good increased) after testifying but only on leading questions. These differential effects of meta-memory feedback on confidence for normal and leading questions are not explained by the cue–belief model. Implications for our confidence judgments are discussed.  相似文献   
939.
Face matching is the act of deciding whether two facial images depict the same person or different people. The real-world face-matching task of checking photo IDs typically occurs under conditions of image-size disparity: A small picture is compared with a life-size face. We examined the effect of image-size disparity on face-matching accuracy. In three experiments, subjects were presented with pairs of equivalently or disparately sized images that depicted the same person or different people. Subjects made same/different judgments and, in two experiments, also reported confidence. Difference detection was significantly poorer given disparate (versus equivalent) image size. Confidence was significantly higher when responses were correct versus incorrect. These findings held whether viewing and decision time was unlimited or limited. Our results raise the practical concern that image-size disparity may undermine difference detection in ID checking, while also indicating that people have some insight into the accuracy of their face-matching judgments.  相似文献   
940.
Higher numeracy has been associated with decision biases in some numerical judgment-and-decision problems. According to fuzzy-trace theory, understanding such paradoxes involves broadening the concept of numeracy to include processing the gist of numbers—their categorical and ordinal relations—in addition to objective (verbatim) knowledge about numbers. We assess multiple representations of gist, as well as numeracy, and use them to better understand and predict systematic paradoxes in judgment and decision-making. In two samples (Ns = 978 and 957), we assessed categorical (some vs. none) and ordinal gist representations of numbers (higher vs. lower, as in relative magnitude judgment, estimation, approximation, and simple ratio comparison), objective numeracy, and a nonverbal, nonnumeric measure of fluid intelligence in predicting: (a) decision preferences exhibiting the Allais paradox and (b) attractiveness ratings of bets with and without a small loss in which the loss bet is rated higher than the objectively superior no-loss bet. Categorical and ordinal gist tasks predicted unique variance in paradoxical decisions and judgments, beyond objective numeracy and intelligence. Whereas objective numeracy predicted choosing or rating according to literal numerical superiority, appreciating the categorical and ordinal gist of numbers was pivotal in predicting paradoxes. These results bring important paradoxes under the same explanatory umbrella, which assumes three types of representations of numbers—categorical gist, ordinal gist, and objective (verbatim)—that vary in their strength across individuals.  相似文献   
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