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991.
Norway rat fetuses (Rattus norvegicus) exhibit a stereotypic behavioral response when the umbilical cord is experimentally compressed with a vascular clamp. In this study, the development of the fetal behavioral response to cord compression was compared in altricial and precocial rodents, which differ markedly in neural and motor maturity at the time of birth. Both altricial and precocial species showed some form of behavioral response to umbilical cord compression. Fetuses of two altricial species, Norway rats and Mongolian gerbils (Meriones unguiculatus), expressed hyperactivity in response to cord compression throughout the last third of gestation. In contrast, precocial cotton rats (Sigmodon hispidus) and spiny mice (Acomys cahirinus) did not respond to cord compression until relatively late in gestation. Thus, altricial and precocial species do not express the cord compression response during comparable periods of neural development: precocial species are much more mature at the earliest expression of this behavior than altricial species. These findings are consistent with the interpretation that the cord compression response is a behavioral adaptation that can promote survival of the fetus in utero.  相似文献   
992.
Learning a bimanual coordination task (synchronization to a visually specified phasing relation) was studied as a dynamical process over 5 days of practicing a required phasing pattern. Systematic probes of the attractor layout of the 5 Ss' coordination dynamics (expressed through a collective variable, relative phase) were conducted before, during, and after practice. Depending on the relationship between the initial coordination dynamics (so-called intrinsic dynamics) and the pattern to be learned (termed behavioral information, which acts as an attractor of the coordination dynamics toward the required phasing), qualitative changes in the phase diagram occurred with learning, accompanied by quantitative evidence for loss of stability (phase transitions). Such effects persisted beyond 1 week. The nature of change due to learning (e.g., abrupt vs. gradual) is shown to arise from the cooperative or competitive interplay between behavioral information and the intrinsic dynamics.  相似文献   
993.
People find their way through cluttered environments with ease and without injury. How do they do it? Two approaches to wayfinding are considered: Differential motion parallax (DMP) is a retinal motion invariant of near and far objects moving against fixation; the information in optical flow (IOF) is a radial pattern of vectors, relying on decomposition of retinal flow. Evidence is presented that DMP guides wayfinding during natural gait, accounting for errors as well as correct responses. Evidence against IOF is also presented, and a space-time aliasing artifact that can contaminate IOF displays is explored. Finally, DMP and IOF are separated, showing they can yield different results in different environments. Thus, it is concluded that (a) DMP and IOF are different, (b) DMP and not IOF is used for wayfinding, (c) moving observers do not usually decompose retinal flow, and (d) optical flow may be a mathematical fiction with no psychological reality.  相似文献   
994.
995.
A multivariate hierarchical model of specific cognitive abilities was fitted to data from 7-year-old adopted and nonadopted sibling pairs in the Colorado Adoption Project in order to assess differential genetic influence on specific mental abilities. Model fitting results and Schmid-Leiman (Schmid & Leiman, 1957) transformations reveal significant heritable variation for verbal, spatial, and memory factors independent of general cognitive ability for the eight ability tests examined. In contrast, environmental influences are primarily measure-specific. The results suggest genetic effects in middle childhood that differentially influence mental ability scores.  相似文献   
996.
A feminist psychospiritual model of therapy that can be used in working with clients who value the spiritual dimension in their lives is offered. The history, philosophy, and work of Women for a New World, a multidisciplinary team of women representing the areas of psychology, religious education, and the arts is presented. Using examples drawn from the developmental history of our retreat-workshop paradigm and from some of our programs, including a weekend retreat for women and a day of reflection for persons affected by AIDS (including family and friends of those with AIDS), the metaphor of therapy as soul healing is developed.  相似文献   
997.
Surprisingly little has been written in the counseling journals on the topic of lying: that is, why some clients consciously choose to be either dishonest with their counselors or deliberately hold back (i.e., keep secrets) important information from their counselors. This article discusses the dynamics of lying and offers suggestions to counselors on how to work with clients who lie.  相似文献   
998.
999.
N-Methyl-D-aspartate (NMDA) receptor antagonists disrupt learning on a variety of tasks. Previous findings indicate that glucose, naloxone, and physostigmine ameliorate learning deficits produced by several treatments. The present experiment examines whether these agents also reverse the amnestic effects of NMDA receptor blockade. Mice were tested for spontaneous alternation performance in a Y-maze. The animals received either saline or the NMDA antagonist, NPC 12626 (35 mg/kg, IP), 50 min prior to testing and received an additional injection of saline, glucose, naloxone, or physostigmine 30 min prior to testing. NPC 12626 significantly decreased alternation scores. Glucose (250 mg/kg), physostigmine (0.01 mg/kg), and naloxone (1 mg/kg) reversed the effects of NPC 12626. Thus, impairments of learning after NMDA receptor blockade share with other amnestic conditions the susceptibility to attenuation by glucose, naloxone, and physostigmine.  相似文献   
1000.
A model of cognitive and affective antecedents and consequences of personal goals, which integrates constructs from social-cognitive and attribution theories, was examined. Data were gathered before and after course examinations in a large university class. Hierarchical and moderated regression analyses supported the model indicating that (1) relationships between self-efficacy, goals, and performance were positive during repeated trials over 4 1/2 months in a naturally occurring setting; (2) the stability dimension of causal attributions moderated the relationship between goal-performance discrepancies and self-efficacy; and (3) the locus of causality dimension of causal attributions moderated the relationship between goal-performance discrepancies and affective responses.We thank Susan Ashford, Jim Austin, Donald Fedor, Ruth Kanfer, Edwin Locke, Paul Nystrom, Donna Randall, Christina Shalley, Masoud Yasai-Ardekani and two anonymous reviewers for their helpful comments on earlier versions of this article. We also thank Eric Dietenberger for his help with graphics.  相似文献   
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