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931.
Stefano Parmigiani Marisa Mainardi Paul F. Brain Marc Haug Vanna Brunoni 《Aggressive behavior》1989,15(3):191-200
Behavioral, physiological (i.e., endocrine), and anatomical consequences of crowding in mice were studied in a situation where animals were in auditory, visual, olfactory, and tactile contact but restrained from full physical interactions, to prevent overt aggression. Males that cohabited with females undisturbed by neighboring conspecifics showed greater propensity to attack same-sex intruders and had higher plasma testosterone levels than did their “crowded” counterparts, that is, males cohabiting with females and housed adjacent to other male/female pairs. In this respect, the latter animals resembled submissive males. However, a significant increase in weight of androgen-dependent target organs (i.e., seminal vesicles and preputial glands) was found in crowded males. These data indicate that despite the observed inhibition of social aggression these males are not physiologically comparable (homologous) to male mice that experienced defeat and the stress of submission during fighting. The intriguing possibility that different conversion pathway of testosterone are accelerated, as a result of social communication, in males living in these two environments and the behavioral implications of these possibilities are discussed. Finally, the parental behavior of crowded animals, although not freely interacting with each other, was disrupted, causing a marked decrease in reproductive success. In this situation a high incidence of infanticide of their offspring by both parents was observed, whereas this behavior was virtually absent in non-crowded male/female pairs. 相似文献
932.
933.
Hansueli F. Etter 《Psychological Perspectives》2020,63(1):106-117
Jung developed over 50?years a paradigmatic idea of an acausal principle, which he called synchronicity. His hypothesis on synchronicity states that, complementary to causality, there exists a further explanatory principle whose effects appear as acausal but meaningful events. Therewith Jung added to the triadic principles of space, time and causality a fourth principle: synchronicity. The experience of individual synchronicities points to a general acausal and meaningful orderedness in nature which apparently exists outside man. Jung published Answer to Job and Synchronicity at the same time, for he attempted to open up a new path to the “state of spiritualization” Beseeltheit of Matter by making the assumption that “being is endowed with meaning.” According to Jung there exists a latent meaning in the cosmos, which existed long before human consciousness developed. He believed that “on the organic level it might be possible to regard biological morphogenesis in the light of the synchronistic factor.” One of many examples in the biological evolution is a Cretaceous-Palaeogene worldwide catastrophe approx. 65 million years ago that resulted in the mass extinction of the dinosaurs. It is understood as the result of a meteorite impact. This catastrophe was a most meaningful chance from the point of view of the mammals, including modern man. We modern humans finally came into existence thanks to a series of cosmic happenings, which were based on causality and synchronicity. What is true for our personal individuation is also true for biological or historical developments: an acausal but meaningful principle is secretly at work. 相似文献
934.
935.
936.
This experiment demonstrated that rats trained to display elevated levels of shock-induced aggression in a negative reinforcement paradigm displayed more boxing behavior than yoked control groups in a later test in which intruder rats were placed in the home cage of resident rats. Resident or intruder status did not affect the influence of the negative reinforcement procedure on the observed resident-intruder behavior of trained animals; however, naive intruders paired with trained residents displayed increased defensive behavior, suggesting that negative reinforcement for shock-induced aggression affected the behavior of these residents. 相似文献
937.
Eric F. Dubow 《Aggressive behavior》1988,14(5):315-324
The relation between aggression and peer social status was investigated in a group of 238 third-through fifth-grade children. Peer social status refers to the degree to which a child is accepted by his or her peer group. By asking children to nominate peers they “like most” and “like least,” one can identify children who are popular, rejected, neglected, or viewed as average within their peer group. Results indicated low to moderate correlations between peer-nominated aggression and global indices of social acceptance. More specifically, it was found that aggressive children largely comprised the rejected and average social status groups, but not the popular or neglected groups. Furthermore, analyses indicated that according to both peers and teachers, aggressive/rejected children showed academic and social-skill deficits, whereas aggressive children of average peer status exhibited adequate adjustment similar to that of nonaggressive/average-status children. These results suggest the importance of considering peer social status when identifying aggressive children in need of intervention and in determining which skill deficits to address. In addition, knowledge of an aggressive child's peer status might be useful in enhancing the predictability of adult adjustment. 相似文献
938.
Many regions around the third ventricle of the brain are thought to participate in the regulation of water intake. In this study we have visualized in acutely hyperosmolar mice the hypothalamic regions by using autoradiography and [14C]deoxyglucose as marker. By applying a recently published, inexpensive, calibrated photographic method for the analysis of the autoradiographs, we can show that the medial parts of the hypothalamus near the third ventricle increased their uptake of deoxyglucose in comparison with the lateral parts. Densitometric measurements confirmed the results. The results also indicate that parts of the medial hypothalamus, even those that are more caudal than the paraventricular nuclei, react to hyperosmolarity. 相似文献
939.
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
940.
E F Rissman 《Behavioral and neural biology》1989,51(1):114-120
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