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951.
Studies examining the effects of day care are reviewed. Little evidence was found indicating a negative impact on child development. A number of weaknesses in the day care literature were pointed out, including problems of ecological validity and failure to examine for differential effects. Suggestions for future research are made, among them a “natural history” of day care and studies of children who have experienced trauma.  相似文献   
952.
Rape has been posited to be an outgrowth of male reproductive strategies. Forced copulations may have evolved as a consequence of the low parental investment made by males in producing and raising offspring. We designed a laboratory experiment which paired rhesus macaque males with females in order to assess the influence of intersexual aggression on male sexual activity. Younger and older adult males had comparable levels of sexual behavior, but younger males were more aggressive towards females than were older males. In addition, females threatened younger males more than older males. Male attacks on females did not result in sexual intercourse. On the contrary, a negative correlation existed between male aggression towards females and male success at achieving intromissions. Female aggression towards males appeared to be an effective tactic which reduced the chances of sexual intercourse. We conclude that intersexual aggression acts either as a mechanism of dominance assertion or as a means to increase spatial distance between individuals. These data do not support the idea that rape in humans has an evolutionary foundation derived from male reproductive strategies.  相似文献   
953.
954.
Male rats were either handled daily or left undisturbed (nonhandled) during the first 21 days of life. At weaning (Day 22) animals in each early treatment condition were assigned to two housing conditions, isolated or grouped, creating four early/late treatment conditions: Handled-Grouped (HG), Handled-Isolated (HI), Nonhandled-Grouped (NHG), and Nonhandled-Isolated (NHI). At maturity, all animals were tested in the latent inhibition (LI, Experiment 1) and the partial reinforcement extinction effect (PREE, Experiment 2) paradigms. In LI, animals receiving prior nonreinforced preexposure to a stimulus (PE) show subsequently retarded conditioning to that stimulus as compared to nonpreexposed (NPE) controls. In the PREE, partially reinforced (PRF) animals exhibit higher resistance to extinction as compared to continuously reinforced (CRF) controls. LI and PREE were obtained in the HG condition, but were impaired in NHG and HI animals. The pattern of impairment was different in the two conditions. The absence of LI in NHG males was due to increased suppression in the PE group, whereas in HI males, was due to decreased suppression in the NPE group. Likewise, the attenuation of the PREE in NHG males stemmed primarily from decreased resistance to extinction in the PRF group, whereas in HI males, it resulted from increased resistance to extinction in the CRF group. The combination of nonhandling and isolation led to the reinstatement of both LI and PREE: normal LI and PREE were obtained in the NHI animals. These results demonstrate that early rearing experience interacts with later experience differentially depending upon the later experience.  相似文献   
955.
Post-training administration of the centrally acting muscarinic agonist oxotremorine (50.0 microgram/kg, ip) facilitated 48-hr retention, in mice, of a one-trial step-through inhibitory avoidance response. Oxotremorine-induced memory facilitation was not prevented by the simultaneous post-training administration of the central beta-adrenoceptor antagonist propranolol (2.0 mg/kg, ip). In contrast, post-training administration of atropine (0.5 mg/kg, ip), but not methylatropine (0.5 mg/kg, ip), completely prevented the facilitatory effects of the central beta-adrenoceptor agonist clenbuterol (30.0 micrograms/kg, ip) on retention. Low subeffective doses of clenbuterol (3.0 micrograms/kg, ip) and oxotremorine (6.25 or 12.5 micrograms/kg, ip) potentiated their effects and facilitated retention when given simultaneously immediately post-training. These results suggest that clenbuterol may induce memory facilitation through an increase of the release of acetylcholine in the brain. Post-training administration of a high dose of clenbuterol (1.0 mg/kg, ip) significantly impaired retention. Clenbuterol (1.0 mg/kg, ip)-induced impairment of retention was completely prevented by simultaneous post-training administration of oxotremorine (6.25, 12.5, or 50.0 micrograms/kg, ip). The centrally acting anticholinesterase physostigmine (21.5 or 68.0 micrograms/kg, ip) partially prevented clenbuterol-induced impairment of memory. The peripherally acting anticholinesterase neostigmine (68.0 micrograms/kg, ip) modified neither retention nor the amnestic effects of clenbuterol. Considered together, these findings are consistent with the view that brain muscarinic cholinergic mechanisms are involved in both the facilitatory and impairing effect of post-training clenbuterol on the modulation of memory storage.  相似文献   
956.

In the present study, we investigated whether parents’ beliefs about their high school aged adolescents’ spatial abilities (i.e., spatial visualization, mental manipulation, and navigation abilities) differed based on their child’s gender. We also examined whether these beliefs related to parents’ encouragement of their child to pursue a Science, Technology, Engineering, or Mathematics (STEM) career as well as students’ actual STEM major and career intentions. Data were collected from 117 pairs of U.S. high school students and one of their parents. We found that parents of young men thought their child had higher mental manipulation and navigation abilities than did parents of young women, even after statistically controlling for adolescents’ actual spatial abilities. Parents who perceived that their child had higher mental manipulation ability were more likely to encourage their child to pursue a STEM career, and those students were more likely to report that they intended to pursue a STEM career. These findings suggest that parents’ beliefs about how good their child is at spatial tasks may be based more strongly on gender stereotypes than on their child’s actual spatial abilities. Helping to make parents aware of these beliefs could be a potential lever of intervention to increase women’s participation in STEM careers.

  相似文献   
957.
Motivation and Emotion - Three studies explored the role of attachment styles as determinants of romantic passion and investigated how the interplay between these variables contributes to conflict...  相似文献   
958.
Bowker  Julie C.  Ooi  Laura L.  Coplan  Robert J.  Etkin  Rebecca G. 《Sex roles》2020,82(7-8):482-492
Sex Roles - Informed by prior work on social withdrawal and gender role norms, the present study utilizes data from a large sample of U.S. (n?=?656) and Canadian (n?=?560)...  相似文献   
959.
Lesbian, gay, and bisexual (LGB) individuals often experience internalized and/or externalized religious rejection due to their sexual orientation. Initial steps in the coming-out process can be especially difficult and can result in existential crises, including questioning one's place within the religious/spiritual realm. The authors propose a developmental framework for conceptualizing the role of religion and spirituality in the coming-out process. Cass's (1979, 1984) stage model of coming out and Genia's (1995) model of religious development, along with additional literature addressing LGB spirituality, serve as foundations for this framework. Counseling and research implications of the framework are also discussed.  相似文献   
960.
In June 2016, the United Kingdom voted to leave the European Union. Voting followed a general trend: disadvantaged areas of the United Kingdom tended to vote “leave,” and more affluent areas tended to vote “remain.” This project investigates the psychological variables underlying this overall trend by distinguishing four psychological motivations: the need for justice, threat reduction needs, need to belong, and the need for control. Participants were recruited from different areas across Greater Manchester (N = 158). A survey assessed voting preference, socioeconomic status, collective relative deprivation (CRD), perceptions of threat from immigration, European and British identification, sense of control in life, and relative gratification. Discriminant function analysis showed that leave voting was characterized by greater realistic threat, symbolic threat, CRD, and British identification. Remain voting was characterized by strong European identification. Findings highlight that a need for justice, threat-reduction needs, and identity needs were key predictors of voting behavior.  相似文献   
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