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961.
Ross J 《Perception》2003,32(7):867-870
Observers in this study judged which of two fields contained the greater number of spots. Spots had difference-of-Gaussian luminance profiles and could differ in contrast polarity or were of uniform luminance and could differ in size. Weber fractions for all observers except one varied little except when spots varied in size. It is suggested that the results of this and previous studies might be explained by the existence of neurons tuned for number.  相似文献   
962.
Despite the prevalence of mentally ill probationers, and probation officers' (POs') central role in their supervision, this is the first reported study to investigate how POs implement mandates to participate in psychiatric treatment. Five focus groups were conducted in major cities with 32 POs and 20 probationers representing a mix of traditional and "specialty" probation agencies. Three key findings resulted. First, there were considerable differences between POs in specialty and traditional agencies in the nature, range, and timing of strategies applied to monitor and enforce treatment compliance. Second, the quality of PO-probationer relationships colored POs' use of these strategies and was perceived as central to probationer outcomes. Relationships characterized by a respectful, personal, approach were perceived as more effective in achieving desired outcomes than those that were more authoritarian. Third, specialty agencies strongly emphasized offender rehabilitation whereas traditional agencies focused more exclusively on community safety. These agencies differed in how well probationers with mental illness "fit" their standard operating procedure. Implications for future research and directions for probation practice are discussed.  相似文献   
963.
964.
965.
Despite widespread use of mental health testimony in cases where violence risk is at issue, relatively little is known about the impact of such information on juror decision-making. This study addressed the effects of testimony based on three types of risk assessment instrument or method (clinical opinion, actuarial assessment, and ratings of psychopathy) to examine whether they would have differential impact on jurors' perceptions of the defendant. In a mock sexually violent predator civil commitment trial, 172 undergraduates were presented a case summary that included prosecution and defense expert testimony related to violence risk based on one of the three methods noted above. Consistent with earlier research, the hypothesis that a defendant described as a "high risk psychopath" by the prosecution would be judged more severely than a defendant judged as "high risk" based on other evaluation procedures was supported, but only among female jurors. Unlike prior studies, little support was found for the hypothesis that clinical opinion testimony would be more influential than actuarially based testimony for either gender. Mechanisms that may underlie the observed gender differences are discussed, as are the potential implications of these findings for civil commitment proceedings.  相似文献   
966.
We investigated a memory-enhancement program that involved teaching older adults to regulate study through self-testing. A regulation group was taught standard strategies along with self-testing techniques for identifying less well-learned items that could benefit from extra study. This group was compared with a strategy-control group, which was taught only strategies, and with a waiting-list control group. Greater training gains were shown for the regulation group (effect size, d = 0.72) than for the strategy-control (d = 0.28) and waiting-list control (d = 0.03) groups, indicating that training a monitoring skill--self-testing--can improve older adults' learning.  相似文献   
967.
The Prospective and Retrospective Memory Questionnaire (PRMQ; Smith, Della Sala, Logie, & Maylor, 2000) was developed to provide a self-report measure of prospective and retrospective memory slips in everyday life. It consists of sixteen items, eight asking about prospective memory failures, and eight concerning retrospective failures. The PRMQ was administered to a sample of the general adult population (N = 551) ranging in age between 17 and 94. Ten competing models of the latent structure of the PRMQ were derived from theoretical and empirical sources and were tested using confirmatory factor analysis. The model with the best fit had a tripartite structure and consisted of a general memory factor (all items loaded on this factor) plus orthogonal specific factors of prospective and retrospective memory. The reliabilities (internal consistency) of the Total scale and the Prospective and Retrospective scales were acceptable: Cronbach's alpha was 0.89, 0.84, and 0.80, respectively. Age and gender did not influence PRMQ scores, thereby simplifying the presentation and interpretation of normative data. To ease interpretation of scores on the PRMQ, tables are presented for conversion of raw scores on the Total scale and Prospective and Retrospective scales to T scores (confidence limits on scores are also provided). In addition, tables are provided to allow users to assess the reliability and abnormality of differences between an individual's scores on the Prospective and Retrospective scales.  相似文献   
968.
It does take a village: nonfamilial environments and children's behavior   总被引:3,自引:0,他引:3  
Abstract - Family characteristics influence children's behavioral development, but so do variations in schools, neighborhoods, and communities. We documented extrafamilial environmental effects by fitting maximum likelihood models to questionnaire data collected from double dyads consisting of twins and their classmate controls. The classmate controls in each double dyad were genetic strangers living in separate households, but they shared school, neighborhood, and community environments with their yoked twin pair and with one another. At ages 11 to 12, the control classmates showed significant similarities in religious practices and smoking and drinking patterns, demonstrating that environmental influences outside the family affect children's behavioral development. Familial self-selection of residential neighborhoods may have contributed to these results, but direct effects of variation across communities, neighborhoods, and schools cannot be dismissed, and such effects warrant further study.  相似文献   
969.
When adults view a test disk embedded in a higher-luminance surround, the perceived lightness of the disk is largely determined by the surround-to-disk (S/D) luminance ratio (Wallach's ratio rule). Performance of 4-month-old infants tested with a forced-choice novelty-preference technique was consistent with predictions based on Wallach's ratio rule. This result suggests that the ability to extract and maintain information about local luminance ratios is present early in infancy. This ability is likely to contribute to the development of lightness constancy.  相似文献   
970.
The cochlear implant is best characterized as a device that provides access to the sound environment. The device enables the hearing pathway to respond to environmental and speech sounds, providing informational cues from the surroundings and from others that may escape visual detection. As the developmental effects of a profound hearing loss are multiple, cochlear implants have been applied to ever younger children in an attempt to promote a more normal level of developmental learning through audition. In deafness, transducer elements of the inner ear fail to trigger auditory nerve afferent nerves in the presence of sound input. However, large reserves of afferent fibers exist even in the auditory nerve of a profoundly deaf patient. Furthermore, these nerve fibers retain the ability to respond to prosthetic activation. Through developmental learning in the early, formative years, auditory centers of the brain appear capable of processing information from the implant to provide speech comprehension and oral language development. Multichannel implants have replaced original single channel designs. multichannel devices enable larger percentages of recipients to recognize the spoken word without visual cues because they provide spectral information in addition to temporal and intensity cues. Testing under conditions of auditory (implant)-only input reveals significant open-set speech understanding capabilities in more than 75% of children after three years of device use. The benefit provided by implants may vary with a number of conditions including: hearing history, age of deafness onset, age at implantation, etiology of deafness, linguistic abilities, and the presence of a motivated system of support of oral language development. Patient variables should be given individual consideration in judging candidacy for a cochlear implant and in planning rehabilitative and education services after surgery and activation of the device.  相似文献   
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