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71.
How do different forms of group alignment influence our attitudes toward outgroups? To answer this, the current fieldwork study explored how identification and identity fusion differentially impact outgroup anxiety, prejudice, and hostility toward rival football fan supporter groups in Australia. The community participants (N = 100) were members of two active fan groups who had experienced a history of intergroup tensions. The findings from the full path model confirmed that the predictor group alignment variables of identification and fusion were correlated, and the two outcome variables of outgroup prejudice and hostility were correlated, as predicted. The findings also revealed that fusion with one's club predicted outgroup hostility, but not prejudice, whereas identification with one's club predicted outgroup prejudice, but not hostility. Additionally, outgroup anxiety was found to significantly mediate the relationship between ingroup identification and outgroup prejudice, whereas a similar relationship was not found for fusion. These findings highlight the differential impact of group alignment (i.e., identification and identity fusion) on social constructs of outgroup anxiety, prejudice, and hostility. Empirically, this is the first study to demonstrate the workings of these distinct group alignment pathways in an applied setting involving hard-core football fans. We discuss the broader implications of these findings for a fuller understanding of the drivers of intergroup tensions and conflict.  相似文献   
72.
Electrical stimulation of the region of the lateral hypothalamus produced a consistent form of quiet-biting attack behavior in cats. In one series of experiments, cats, implanted with electrodes from which attack had been elicited, were anesthetized and then were injected with a bolus of 14C-2-deoxyglucose at the same time as electrical stimulation was delivered through the attack electrodes. Brains prepared for X-ray autoradiography revealed that lateral hypothalamic stimulation activated the classical medial forebrain bundle pathway supplying the septal region, diagonal band, lateral preoptic area, and ventral tegmental region. Stimulation of quiet-attack sites in perifornical hypothalamus resulted in the activation of a much more extensive projection system which included the central and lateral tegmental fields of the midbrain and pons, and central gray region, as well as the structures described above. In a second series of experiments, 3H-leucine was placed into the region of the electrode tip from which attack was elicited in order to identify more precisely the pathways arising from that site. In general, tritiated amino acid radioautography replicated the 14C-2-deoxyglucose findings. In addition, the amino acid radioautographic data revealed the presence of extensive projections from perifornical hypothalamus to such pontine structures as the nucleus locus coeruleus, motor nucleus of NV , and the lateral pontine tegmental field. The functional connections between the lateral hypothalamic “attack region” and lateral preoptic zone were also confirmed by electrophysiological methods.  相似文献   
73.
Male and female rats react differently to losing an aggressive encounter, the presence of testosterone (at the time of confrontation) being a critical factor in the manifestation of this sex difference. Female rats were androgenized by 250 μg testosterone propionate sc on days 1 and 5 after birth. When adult they received a sc testosterone proprionate (TP) implant and were subjected to repeated defeats by being placed in the cage of an aggressive resident female. In contrast to males, which freeze and become permanently submissive, androgenized females showed no freezing or other signs of submission. The sex difference in response to defeat is therefore not dependent on the presence of testosterone during the period of post-natal sexual differentiation.  相似文献   
74.
This study explores connections between inward-directed violence and outward-directed violence using data from the Reach for Health sample, which was originally recruited in the 1990s from three middle schools in economically distressed, predominantly African American neighborhoods of New York City. Now in their thirties, participants (N = 595) completed surveys assessing current suicidal thoughts and behaviors as well as other violence involvements, including intimate partner violence victimization and perpetration. About 10% of males and females reported any suicidal ideation or attempt in the past 12 months. In logistic regression analyses adjusting for sociodemographics, prior reports of feeling blue in middle school (OR: 1.12, CI: 1.02–4.39) and young adult suicidality (OR: 2.54, CI: 1.30–4.95) are significantly related to later suicidality. So are concurrent aggressive behaviors, including reports of physical fighting outside the home (OR: 2.70, CI: 1.29–5.67) and IPV perpetration (OR: 2.09, CI: 1.11–3.94). Neither IPV victimization nor witnessing neighborhood violence is correlated. Findings shed light on the persistence of suicidality in the lives of those who come of age, and often remain, in communities with high levels of poverty, and confirm linkages of suicidality with externally directed aggression. Life-stage interventions are needed to counter the interwoven causes and consequences of multiple forms of violence.  相似文献   
75.
Neuropsychology Review - A transient improvement in cognitive performance can be observed following the ingestion of a glucose drink, a phenomenon known as the ‘glucose facilitation...  相似文献   
76.
Rats with cannulas aimed at the posteroventral (PV) or ventrolateral (VL) areas of the caudate nucleus were trained on a conditioned emotional response (CER) task. Post-training microinjections of the indirect catecholamine agonist, d-amphetamine (5 micrograms), or of the dopamine D2 receptor agonist, LY171555 (1 microgram), into the PV area improved retention of a CER with a visual CS, but had no effect on a CER with an olfactory CS. Post-training injections of the same two drugs into the VL area improved retention of a CER with an olfactory CS, but had no effect on a CER with a visual CS. Post-training injections of the dopamine D1 receptor agonist, SKF38393 (0.5, 1.0, 2.0 micrograms), into either site had no effects on either CER. These findings suggest that different areas of the caudate nucleus mediate acquisition of CERs with different CSs, possibly implicating the topographically organized corticostriatal innervation in the acquisition of certain types of memories in the caudate nucleus. The findings also suggest that dopamine D2 receptors in the caudate nucleus are involved in the acquisition of these CERs.  相似文献   
77.
Male gerbils have larger ventral scent glands, and they mark more than females. In both sexes, scent gland activity is dependent on gonadal hormones. Observations on colonies of gerbils, living in enclosures or cages, showed that both scent gland size and marking behaviour were related to social status. In colonies founded by a single pair, breeding was confined to the original female. The infertility of the daughters was due to failure of sexual maturation. As this was always associated with a lack of development of the scent glands, the functional state of the latter could be used as an index of fecundity. A change in social organization (eg removal of the parents) caused previously infertile females to conceive and was accompanied by development of the scent glands If there was competition for dominance, the scent glands of the losers regressed; at autopsy, their ovaries and uteri appeared to be nonfunctional. The founding father usually had a larger scent gland than his sons, but the inhibition of sexual function was not as severe as in the females. However, the father characteristically showed much more marking behaviow in a neutral territory than his sons. None of the fem ales-except the mother-showed appreciable marking, and her scores were much lower than those of the dominant male. Asymptotic populations were reached at about the same level in enclosures and cages, implicating an intrinsic capacity for control independent of the number of animals per unit of space but probably related to the natural size of a social group. Stabilization of numbers was achieved not only by reproductive inhibition of young females, but also by cessation of breeding by the founding mother and death of litters. Littermates raised in enclosures without their parents showed delayed sexual maturation accompanied by fighting which resulted in the formation of a hierarchy headed by a breeding female and a dominant (marking) male.  相似文献   
78.
Laboratory rats were used to investigate sex and strain differences in the effects of aggression on a cooperative behavior in which pairs learn to coordinate shuttling in a rectangular chamber. The level of aggression was manipulated by comparing males and females of the aggressive S3 strain and a less aggressive Sprague-Dawley-derived strain and by housing same-sex partners either together or individually (eight groups, n = 7 pairs per group). Hormone levels were stabilized by gonadectomy and daily injections of the appropriate sex hormone. The only serious coordination deficits were in individually housed males, associated with violent fighting and an extreme dominance/subordinance relationship that was not observed in females. All other groups readily learned and performed the coordination, with evidence that low and moderate levels of aggression could facilitate coordination by evoking species-typical behaviors that increased proximity, synchrony, and differentiation within pairs. The discussion focused on models of affiliative behavior in the study of aggression and the compatibility between moderate levels of aggression and cooperation.  相似文献   
79.
Laboratory rats were used to investigate sex and strain differences in the effects of aggression on a cooperative behavior in which pairs learned to coordinate shuttling in a rectangular chamber. The level of aggression was manipulated by comparing males and females of the aggressive S3 strain and a less aggressive Sprague-Dawley-derived strain and housing same-sex partners either together or individually (8 groups, n = 7 pairs per group). Hormone levels were stabilized by gonadectomy and daily injections of the appropriate sex hormone. The only serious coordination deficits were in individually housed males, associated with violent fighting and an extreme dominance/subordinance relationship that was not observed in females. All other groups readily learned and performed the coordination with evidence that low and moderate levels of aggression could facilitate coordination by evoking species-typical behaviors that increased proximity, synchrony, and differentiation within pairs. The discussion focused on models of affiliative behavior in the study of aggression and the compatibility between moderate levels of aggression and cooperation.  相似文献   
80.
The mechanisms of extinction were examined by reducing the intensity of the unconditioned stimulus (US) after acquisition training to determine whether such reductions lie on a continuum with CS-alone extinction. The experiments revealed that reductions in US intensity yielded extinction-like effects. Specifically, there were proportional reductions in the daily mean level of responding across sessions. There were also persistent within-session declines and between-session increases of responding analogous to spontaneous recovery. Surprisingly, even when US intensity was held constant, within-session declines and between-session increases were apparent. The results are discussed with respect to possible contributions from unlearning, new learning, generalization decrement, and nonassociative loss, especially CS-specific attentional changes and CR-specific reactive inhibition.  相似文献   
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