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991.
During the perinatal period, the developing brain is sensitive to environmental events. Deleterious programing resulting from infection, dietary restriction, or psychological stress has been observed and affects adult immune and endocrine systems as well as behavior. In this study, we determined whether neonatal infection permanently alters immune and glucocorticoid receptor signaling pathways in the adult hippocampus. A Chlamydia muridarum respiratory infection was induced in male and female mice at birth. Mice were allowed to recover and microarray analysis was conducted on RNA from adult hippocampal tissue. In males, neonatal infection induced an up-regulation of genes associated with cellular development, nervous system development and function, such as cyclin-dependent kinase inhibitor 1A. After neonatal infection, adult females exhibited a T-helper 2 immune bias with genes such as major histocompatibility complex, class II, DQ beta 1 up-regulated. Expression of prolactin, vasopressin, hypocretin, corticotrophin-releasing hormone-binding protein, and oxytocin were confirmed by quantitative real-time polymerase chain reaction. This study shows that neonatal infection differentially alters the gene expression profiles of both female and male mice along immune and neuroendocrine pathways.  相似文献   
992.
Research shows that scent enhances memory for associated information. Current debate centers around scent's immunity to “retroactive interference,” i.e., reduced memory for earlier-learned information after exposure to additional, subsequently-learned information. This paper demonstrates that scent-enhanced memory is indeed prone to retroactive interference, but that some of the information lost is restored using a scent-based retrieval cue. Two process explanations for interference effects are proposed, with the evidence providing more support for an inhibition rather than a response competition explanation. The results enhance our understanding of the encoding and retrieval of olfactory information from long-term memory, and reasons why interference occurs.  相似文献   
993.
Literature regarding fathers of children with autism remains sparse, and because mothers are the more common intervening parent, few training methods have focused on fathers. Thus, we sought to evaluate effects of in-home training directed at fathers and their ability to train mothers in the same manner in which they were trained. Fathers were taught four skills commonly associated with in-home training interventions for parents of children with autism: following the child’s lead, imitation with animation, commenting on the child, and expectant waiting. Father skills were evaluated twice a week for 12 weeks during videotaped in-home father–child play sessions. Analyses included visual inspection of graphed data and statistical analyses of father skill acquisition, mother skill acquisition, and child behaviors with both parents. A multivariate repeated measures analysis of 18 dyads revealed significant increases in frequencies of fathers’ imitation with animation, expectant waiting, and commenting on the child. Child initiating rates increased significantly as did frequencies of child non-speech vocalizations. Analysis of mothers revealed significant increases in frequencies of imitation with animation, expectant waiting, and following the child’s lead. Child behaviors had similar results for father and mother sessions. Findings are consistent with those from our first study indicating that fathers can effectively implement skills that promote father–child social interactions and that children respond positively to this approach.  相似文献   
994.
Numerous studies have suggested that the amygdala is involved in the formation of aversive memories, but the possibility that this structure is merely related to any kind of fear sensation or response could not be ruled out in previous studies. The present study investigated the effects of bilateral inactivation of the amygdaloid complex in rats tested in the plus-maze discriminative avoidance task. This task concomitantly evaluates aversive memory (by discrimination of the two enclosed arms) and innate fear (by open-arm exploration). Wistar rats (3-5 months-old) were implanted with bilateral guide cannulae into basolateral amygdala. After surgery, all subjects were given 1 week to recover before behavioral experiments. Afterwards, in experiment 1, 15 min prior to training, 0.5 μl of saline or muscimol (1 mg/ml) was infused in each side via microinjection needles. In experiment 2 the animals received injections immediately after the training session and in experiment 3 rats were injected prior to testing session (24 h after training). The main results showed that (1) pre-training muscimol prevented memory retention (evaluated by aversive arm exploration in the test session), but did not alter innate fear (evaluated by percent time in open arms); (2) post-training muscimol impaired consolidation, inducing increased percent in aversive arm exploration in the test session and (3) pre-testing muscimol did not affect retrieval (evaluated by aversive enclosed arm exploration in the test session). The results suggest that amygdala inactivation specifically modulated the learning of the aversive task, excluding a possible secondary effect of amygdala inactivation on general fear responses. Additionally, our data corroborate the hypothesis that basolateral amygdala is not the specific site of storage of aversive memories, since retention of the previously learned task was not affected by pre-testing inactivation.  相似文献   
995.
Human vision is sensitive to salient features such as motion. Therefore, animation and onset of advertisements on Websites may attract visual attention and disrupt reading. We conducted three eye tracking experiments with authentic Web pages to assess whether (a) ads are efficiently ignored, (b) ads attract overt visual attention and disrupt reading, or (c) ads are covertly attended with distraction showing up indirectly in the reading performance. The Web pages contained an ad above a central text and another ad to the right of the text. In Experiments 1, 2, and 3A the task was to read for comprehension. Experiment 1 examined whether the degree of animation affects attention toward the ads. The results showed that ads were overtly attended during reading and that the dwell times on ads were the longest when the ad above was static and the other ad was animated. In Experiments 2 and 3, the ads appeared abruptly after a random time interval. The results showed that attention (i.e., the time when the eyes first entered an ad) was related to the ad onset time. This happened especially for the ad to the right, indicating that ads appearing close to the text region capture overt attention. In Experiment 3B the participants browsed the Web pages according to their own interest. The study demonstrated that salient ads attract overt visual attention and disrupt reading, but during free browsing, ads were viewed more frequently and for longer time than during reading.  相似文献   
996.
In 1999, Wilkinson and the Task Force on Statistical Inference published "Statistical Methods and Psychology: Guidelines and Explanation." The authors made several recommendations about how to improve the quality of Psychology research papers. One of these was to report some effect-size index in the results of the research. In 2001, the fifth edition of the Publication Manual of the American Psychological Association included this recommendation. In Spain, in 2003, scientific journals like Psicothema or the International Journal of Clinical and Health Psychology (IJCHP) published editorials and papers expressing the need to calculate the effect size in the research papers. The aim of this study is to determine whether the papers published from 2003 to 2008 in the four Spanish journals indexed in the Journal Citation Reports have reported some effect-size index of their results. The findings indicate that, in general, the followup of the norm has been scanty, though the evolution over the analyzed period is different depending on the journal.  相似文献   
997.
Moral theory is an important guide to bioethical decision-making, but it can confuse and mislead those who offer ethical advice to clinicians and researchers, delaying decisions that must be made in a timely fashion. In this paper I examine the ways moral theory can lead bioethicists astray. Absent a sensitivity to the empirical realities of ethical problems, moral theory 1) contributes to the disappearance of the persons caught in an ethical quandary, 2) focuses on the puzzle-solving rather than examining the conditions that generate moral problems, and 3) universalizes ethical dilemmas, overlooking local processes for resolving moral questions. Taken together, empirically informed moral theory and theoretically informed empirical research can help bioethicists transcend the is/ought problem in ethical work.  相似文献   
998.
Educational research and practice could benefit from and contribute to multi-disciplinary study of well-being. In particular, research on the well-being of youth within and beyond school may benefit students, educators, administrators, and the community. This review provides a conceptual framework that (a) integrates research on well-being from economics, sociology, psychology and the health sciences, (b) organises this literature within seven domains of inquiry: Having, Being, Relating, Thinking, Feeling, Functioning, and Striving, and (c) highlights research pertinent to senior high school level educational experiences. This framework provides an important foundation from which further research on well-being can be developed.  相似文献   
999.
In communities of high biodiversity, the ability to distinguish predators from non-predators is crucial for prey success. Learning often plays a vital role in the ability to distinguish species that are threatening from those that are not. Many prey animals learn to recognise predators based on a single conditioning event whereby they are exposed to the unknown predator at the same time as alarm cues released from injured conspecifics. The remarkable efficiency of such learning means that recognition mistakes may occur if prey inadvertently learn that a species is a predator when it is not. Latent inhibition is a means by which prey that are pre-exposed to an unknown species in the absence of negative reinforcement can learn that the unknown animal is likely not a threat. Learning through latent inhibition should be conservative because mistakenly identifying predators as non-predators can have fatal consequences. In this study, we demonstrated that a common coral reef fish, lemon damselfish, Pomacentrus moluccensis can learn to recognise a predator as non-threatening through latent inhibition. Furthermore, we showed that we could override the latent inhibition effect by conditioning the prey to recognise the predator numerous times. Our results highlight the ability of prey fish to continually update the information regarding the threat posed by other fishes in their vicinity.  相似文献   
1000.
Sexual infidelity can be costly to members of both the extra-pair and the paired couple. Thus, detecting infidelity risk is potentially adaptive if it aids in avoiding cuckoldry or loss of parental and relationship investment. Among men, testosterone is inversely related to voice pitch, relationship and offspring investment, and is positively related to the pursuit of short-term relationships, including extra-pair sex. Among women, estrogen is positively related to voice pitch, attractiveness, and the likelihood of extra-pair involvement. Although prior work has demonstrated a positive relationship between men?s testosterone levels and infidelity, this study is the first to investigate attributions of infidelity as a function of sexual dimorphism in male and female voices. We found that men attributed high infidelity risk to feminized women?s voices, but not significantly more often than did women. Women attributed high infidelity risk to masculinized men?s voices at significantly higher rates than did men. These data suggest that voice pitch is used as an indicator of sexual strategy in addition to underlying mate value. The aforementioned attributions may be adaptive if they prevent cuckoldry and/or loss of parental and relationship investment via avoidance of partners who may be more likely to be unfaithful.  相似文献   
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