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951.
Abstract. A scientist (for whom the world is the universe) and a theologian (for whom the world is planet Earth) engage in dialogue, not contrived Platonic or Galilean dialogue, but true bidisciplinary dialogue that strives for higher viewpoint. S: Is the preservation of the human species a primary human responsibility? T: It may be a responsibility we share with God. S: The human species has a limited future if confined to the planet Earth. We must diversify our habitat by colonizing space. T: We are responsible for other life on the planet as well. The discussants conclude that besides protecting Earth ecologies, we should create new ecologies in space.  相似文献   
952.
MUST FIGURE-GROUND ORGANIZATION PRECEDE OBJECT RECOGNITION?   总被引:2,自引:1,他引:1  
The assumption that figure-ground segmentation must precede object or shape recognition has been central to theories of visual perception We showed that assumption to be incorrect in an experiment in which observers reported the first perceived figure–ground organization of briefly exposed stimuli depicting two regions sharing a figure–ground border We manipulated the symmetry of the two regions and their orientation-dependent denotivity (roughly, their meaningfulness), and measured how each of these variables influenced figure–ground reports when the stimuli were exposed for 14, 28, 57, 86, or 100 ms, and followed immediately by a mask Influences on figure–ground organization from both symmetry and orientation-dependent object recognition processes were found, both were observed first in the 28-ms condition Object recognition inputs did not dominate symmetry inputs We suggest that object recognition processes may operate simultaneously on both sides of edges detected before figure–ground relationships are determined  相似文献   
953.
Until recently, little attention has been paid to the possibility of cognitive deficits in patients with disease or failure of major organs such as the liver, kidney, or heart. However, there is a growing awareness that major organ failure often has neuropsychological sequelae. These sequelae may at times be quite subtle and not detectable under gross. examination. Nevertheless, even subtle deficits may have a major impact on adherence to medical regimens, psychosocial adjustment, and quality of life of patients. Neuropsychological assessment has a potentially valuable role to play both in research and in clinical work. It can be useful in adding to our knowledge of the cognitive effects of various types, severity and duration of major organ disease, as well as sequelae associated with treatment. It also is a potentially valuable clinical tool for identifying cognitive deficits that will affect the quality of life and probability of survival for organ failure patients.  相似文献   
954.
In this journal, Palmer and Rock (1994) articulated a principle of perceptual organization calleduniform connectedness (UC); and they contended that previous investigators of perception had failed to realize the need for this organizing principle. The authors outlined a theory of perceptual organization that “places the principle of UC at center stage” (p. 38) in that UC was assigned the two privileged roles of (1) forming the fundamental units for later perceptual processes, and (2) yielding the postconstancy regions that correspond to environmental surfaces. In this commentary, I argue that the proposed theory entails a serial ordering of perceptual processes that is inconsistent with current evidence regarding figure-ground organization, stereo fusion, and object recogntion. In addition, I point out that Kurt Koffka (1935) recognized the need for a principle of unit formation similar to the one proposed by Palmer and Rock.  相似文献   
955.
Multiple treatment interventions including instructions, modelling, timeout, avoidance of repetition, and reinforcement were successful in establishing factual answers to personal background questions in a withdrawn and socially unresponsive chronic schizophrenic. The subject had previously persisted in giving only delusional responses to these questions. A multiple-baseline design across verbal replies to personal background questions demonstrated that the changes in behavior were brought about by the treatment interventions. During baseline, the subject was reinforced for any response to four questions. The experimental interventions were then introduced for the first question and moved sequentially to an additional question when the subject's responses reached the criterion of at least 80% correct for two consecutive sessions. Introduction of the experimental interventions produced an increase from a baseline level of zero to at least 80% correct for each question. The use of the token reinforcement procedure was faded out after the subject was able to answer all four questions correctly at least 80% of the time for two consecutive sessions. Fading of the token reinforcement procedure was accomplished by using increasingly intermittent schedules of token reinforcement during the last seven sessions. In the final session, no tokens were used to reinforce the subject's responding. Nine-, ten-, and 12-month followup interviews were conducted to evaluate the maintenance of treatment gains. Maintenance was found to be complete at the nine- and 10-month followups, but at the 12-month followup interview, the subject answered one question incorrectly. This study replicates an investigation previously reported in this journal.  相似文献   
956.
The biomotometer, an electronic device that simultaneously measures activity and provides auditory feedback to the subject, was used in combination with material reinforcers in two experiments attempting to modify activity level in children. In the first study the activity level of an 11-year-old highly active boy was decreased below mean baseline during conditioning in a classroom setting. His level of activity returned to baseline when feedback was withdrawn. In the second study, activity level of a 10-year-old hypoactive boy was increased over mean baseline level during conditioning in a free-play setting, and returned to slightly below baseline during five extinction trials. Results of these studies indicate that the biomotometer is a useful instrument for modification of activity level.  相似文献   
957.
The purpose of the present study was to investigate four traditionally male occupations and four traditionally female occupations on a number of dimensions which people use to judge the prestige or importance of a job. Workers were pictured on one form in their traditional roles and on a second form in nontraditional roles. Results indicated a tendency for subjects to give lower ratings to workers in nontraditional jobs. More importantly, for the two “objective” dimensions, money and education, boys and girls agreed on job ratings; however, on the two more “subjective” dimensions, respect and importance to the community, boys gave higher ratings to the male jobs, while girls gave higher ratings to the female jobs.  相似文献   
958.
Activity level of 13 boys (aged 9–13) from a day hospital program was measured using actometers in classroom, gym, woodshop, and group therapy settings. Ratings of Ss' activity were obtained from mothers using the Werry scale, and from six clinical staff familiar with the Ss using the Davids scale. It was predicted that activity ratings would have situationally specific relationships with actometermeasured activity level according to the rater's opportunities for observation. Comparisons between measures indicated that all clinical staff ratings correlated significantly with actometer activity in the classroom (r=.49 to r=.73), while mothers' ratings correlated significantly with actometer activity in gym (r=.67), and woodshop (r=.77), and with overall activity (r=.65), a combined measure derived from actometer scores in the four conditions tested. Five of six clinical staff raters showed significant interrater reliability (r=.58 to r=.83). Results are discussed in terms of their implications for solution of current problems in assessment of activity level and hyperactivity.  相似文献   
959.
Perceptual and projective aspects of body image in obese youngsters (not in psychological treatment) and normal-weight youngsters 8–9 years of age and 12–13 years of age were investigated. The results indicate that perceptual distortions in estimating various body dimensions of oneself are primarily a function of age rather than weight status. The accuracy of estimating the weight of peers and an adult showed an association with the sex of the subject. No group differences were found in terms of projective aspects of body image as measured by barrier and penetration responses. This study suggests that obese youngsters in the middle childhood and entering puberty periods in comparison to normal-weight youngsters of the same age do not manifest differences in perceptual factors of body image.  相似文献   
960.
The incidence of stuttering has always been reported to be higher in males than in females. Possible causes of the unequal sex ratio include various ascertainment biases, incomplete reporting, social role differences, X-linked inheritance, or a combination of environmental and genetic elements. Each of these factors has been examined against data collected in the large family study of stuttering, and all but one have been eliminated. Only the gene-environment interaction hypothesis can be supported by the data. Statistical analysis confirms that the sex effect in stuttering is real and supports a threshold model for the sex difference. We conclude that the possibility of differences between males and females must be considered in any etiological research in stuttering.  相似文献   
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