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971.
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   
972.
973.
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   
974.
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   
975.
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   
976.
977.
Wistar rats (n = 95) were trained in a pole-jumping apparatus (10 trials/session/day) to investigate the involvement of centrally and peripherally released endogenous AVP in their acquisition rate and to examine the feasibility of the microdialysis technique for the administration of peptides during a behavioral test. After session 1, a microdialysis probe was implanted into the septum; during sessions 2 and 3 the probe was perfused with artificial cerebrospinal fluid (aCSF) alone or containing either AVP (delivered amount via the probe: 0.2 ng) or the V1 (d(CH2)5Tyr(Me)AVP, 5.0 ng) or the V2/V1 (d(CH2)5-D-Tyr(Et)VAVP, 5.0 ng) antagonist. Administration of AVP via microdialysis into the septum failed to alter the acquisition rate of pole jumping. Also, ip application of both hypertonic saline and the AVP V1 antagonist (10 micrograms) in another experiment failed to show a significant effect upon behavior. Septal administration of the V1 or the V2/V1 antagonist via microdialysis, however, produced a significantly impaired performance. The results indicate that AVP release within the septum is involved in the acquisition of pole-jumping behavior probably mediated by the V1 receptor subtype. An additional involvement of the V2 receptor subtype, however, cannot be entirely excluded. The microdialysis technique proved to be a potent tool to administer substances concomitantly with behavioral tests.  相似文献   
978.
Reminder treatments have been shown to facilitate the retrieval of a variety of conditioned responses. Whether or not similar results would occur with an experimental paradigm which involves primarily memory for a stimulus, i.e., where no particular response is specified, is unclear. Accordingly, using Sprague-Dawley rats, we employed a latent inhibition paradigm with a long (10 days) retention interval between sucrose (CS) preexposure and sucrose-illness pairing (training). The results demonstrated a loss of latent inhibition following the 10-day retention interval suggesting "forgetting" of the CS preexposure. However, placing a single reminder exposure to the CS within the preexposure-to-training interval reinstated the preexposure effect. Controls indicated that in the absence of the initial preexposure the reminder per se did not produce latent inhibition. Thus, a reminder can reinstate a stimulus attribute (flavor representation) and explicit conditioned responses.  相似文献   
979.
The Companeros model of HIV infection prevention in Ciudad Juarez, Mexico, is presented as conceived by the National Institute of Drug Abuse (NIDA). 518 women who were IV drug users, sexual partners of drug addicts, or prostitutes were requested to participate, and 232 consented. Initial and follow-up AIDS assessments were utilized along with an assessment of sociodemographic variables, including knowledge, sexual behavior, use and abuse of drugs, and previous health history. Educative sessions about AIDs and sexually transmitted diseases (STDs) included group discussions and interaction, video watching, personal experiences, and sociodramas. 61% of prostitutes were 29, 12.6% were 13-19 years old, 31.1% were aged 30-39, and 8.9% were 40. 11% had no formal education, 58% had 6 years of primary and part of 3 years of secondary education, only 18.6% completed secondary education; and 13% had higher education. 19% lived in a hotel or shelter. Family disintegration reached 44%; these women did not live with their children. Only 5.2% thought they had excellent health, 51% said they had good health, 31% stated they had average health, and 12% admitted having had health problems. 14.6% had genital ulcers, 1.3% had herpes, 15% had gonorrhea, and 10% had syphilis. Since IV drug use among these women was almost nonexistent sexual relations constituted the principal risk factor. Responses to a questionnaire showed that the most frequent sexual behavior was vaginal penetration followed by fellatio; anal penetration was less common. 34.9% of the women practiced fellatio without protection, 16.3% had anal intercourse without protection. The proportion of AIDS cases in Mexico in women of reproductive age was growing at an exponential rate, possible because of misinformation about AIDS, a history of STDs, and a low rate of condom use.  相似文献   
980.
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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