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961.
The hippocampus, which is critically involved in learning and memory processes, is known to be a target for the neuromodulatory actions of steroid hormones produced by the adrenal glands and gonads. Much of the work of B.S. McEwen and collaborators has focused on the role of glucocorticosteroids and estrogen in modulating hippocampal plasticity and functions. In addition to hormones derived from the endocrine glands, cells in the hippocampus may be exposed to locally synthesized neurosteroids, including pregnenolone, dehydroepiandrosterone and their sulfated esters as well as progesterone and its reduced metabolites. In contrast to hormones derived from the circulation, neurosteroids have paracrine and/or autocrine activities. In the hippocampus, they have been shown to have trophic effects on neurons and glial cells and to modulate the activity of a variety of neurotransmitter receptors and ion channels, including type A gamma-aminobutyric acid, N-methyl-D-aspartate and sigma receptors and N- and L-type Ca2+ channels. There is accumulating evidence that some neurosteroids, in particular pregnenolone sulfate, have strong influences on learning and memory processes, most likely by regulating neurotransmission in the hippocampus. However, the hippocampus is not the only target for the mnesic effects of neurosteroids. Associated brain regions, the basal nuclei of the forebrain and the amygdaloid complex, are also involved. Some neurosteroids may thus be beneficial for treating age- or disease-related cognitive impairments. 相似文献
962.
Reene M. Sterling Patricia M. Barbetta William L. Heward Timothy E. Heron 《Journal of Behavioral Education》1997,7(2):151-165
An alternating treatments design was used to compare the effects of active student response (ASR) and on-task (OT) instruction on the acquisition and maintenance of health facts during small-group lessons. Five students with learning difficulties (4 students identified as developmentally handicapped and 1 student identified as learning disabled) participated in daily instruction on weekly sets of 20 unknown health facts (10 facts assigned to the ASR condition and 10 to the OT condition). During ASR instruction, the teacher modeled the correct response to a health question that was presented visually on a health fact card, and the students immediately repeated the correct response in unison three times. During OT instruction, students attended visually to the health fact card as the teacher modeled the correct response. All 5 students made more correct responses on end-of-day tests on health facts taught with ASR instruction than they did on health facts taught with OT instruction. ASR instruction also produced consistently superior results on maintenance tests administered 2 weeks after instruction. 相似文献
963.
Mosier KL Skitka LJ Heers S Burdick M 《The International journal of aviation psychology》1997,8(1):47-63
Automated aids and decision support tools are rapidly becoming indispensable tools in high-technology cockpits and are assuming increasing control of"cognitive" flight tasks, such as calculating fuel-efficient routes, navigating, or detecting and diagnosing system malfunctions and abnormalities. This study was designed to investigate automation bias, a recently documented factor in the use of automated aids and decision support systems. The term refers to omission and commission errors resulting from the use of automated cues as a heuristic replacement for vigilant information seeking and processing. Glass-cockpit pilots flew flight scenarios involving automation events or opportunities for automation-related omission and commission errors. Although experimentally manipulated accountability demands did not significantly impact performance, post hoc analyses revealed that those pilots who reported an internalized perception of "accountability" for their performance and strategies of interaction with the automation were significantly more likely to double-check automated functioning against other cues and less likely to commit errors than those who did not share this perception. Pilots were also lilkely to erroneously "remember" the presence of expected cues when describing their decision-making processes. 相似文献
964.
“Are False Memories Permanent?”: An Investigation of the Long-Term Effects of Source Misattributions
With growing concerns over children's suggestibility and how it may impact their reliability as witnesses, there is increasing interest in determining the long-term effects of induced memories. The goal of the present research was to learn whether source misattributions found by Ceci, Huffman, Smith, and Loftus (1994) caused permanent memory alterations in the subjects tested. When 22 children from the original study were reinterviewed 2 years later, they recalled 77% of all true events. However, they only consented to 13% of all false events, compared to the 22% false consent rate (among the same subset of children) found by Ceci et al. (1994). Additionally, while children remained accurate in their recall of true events (they maintained assents 78% of the time), they “recanted” their earlier false consents 77% of the time, after the 2-year delay. Implications of these findings for child witnesses and the legal system are discussed. 相似文献
965.
Diane M. Browder Linda M. Bambara Phillip J. Belfiore 《Journal of Behavioral Education》1997,7(4):519-528
Instruction is a variable that has enhanced community access for adults with developmental disabilities. Community-based instruction emerged as an especially useful format to teach individuals daily living and work skills in the settings where skills would be used. As advocacy and self-advocacy for individuals with developmental disabilities increased, professionals recognized the importance of empowerment and self-determination in gaining community access. Adult education that incorporates the values of person-centered planning will evolve beyond what has traditionally been viewed as community-based instruction. This article describes the characteristics of community-based instruction designed to enhance not only community access, but also the participant's overall quality of life. 相似文献
966.
Paul M. Kohn Colleen O'Brien Donna I. Pickering 《Personality and individual differences》1997,22(6):895-899
Adaptiveness constitutes coping consistently with Stressors so to reduce distress or, at worst, not aggravate it. Accordingly, it should moderate the adverse impact of hassles. Undergraduate volunteers (N = 200) responded to measures of hassles, adaptiveness, and the criteria of subjective distress, psychiatric symptomatology and minor physical ailments. In all three regression analyses, hassles made a substantial positive contribution and adaptiveness a small negative contribution to adverse outcome. The interaction between hassles and adaptiveness was non-significant in all three cases. Alternative interpretations were identified to guide further research. 相似文献
967.
968.
This focus section has presented Japanese research on a variety of socialization agents and contexts, including mothering, fathering, peers and multiple-caretakers in families and institutions. The reader is encouraged to compare the papers, discover the theoretical and applied implications of each study for child development in the reader's own culture, and to pursue collaborations with the outstanding young Japanese contributors. We conclude with brief comments on each of the five articles, discussing their limitations, most significant findings, theoretical importance, and implications for subsequent research. 相似文献
969.
Research based mainly on non-national samples reports a greater affinity for animal rights among women than men, and proposes a greater relational role orientation among women that emphasizes caring for others to explain this difference. Using a recent national sample comprised of 11% African American and 89% white American respondents, we find that a relational role orientation fails to account for women’s greater support of animal rights. It does provide minor help in distinguishing animal rights advocates from nonadvocates, but only among women and only on one of two measures of animal rights support. We conclude by proposing women’s structural locations as well as the interplay between these locations and women’s role socialization as alternate explanations for gender differences in affinity for animal rights. 相似文献
970.
A person-perception study was conducted to examine the influence of intimacy and commitment on the acceptability of premarital sex and contraceptive preparedness. Ninety-six women rated a female target's personality and behavior after reading a diary entry describing a couple's initial sexual encounter. The nature of the couple's relationship and who provided the condom were manipulated between participants. Women inferred a committed relationship when intimacy was present. Women rated the target, and her behavior, as more acceptable when she had sex in a relationship with commitment. When she provided a condom, the target was perceived as less nice in the noncommitted than in the committed relationship. When her partner provided the condom, however, commitment level did not influence personality ratings. 相似文献