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991.
We recently found (Schneider, Moraglia, & Jepson, 1989) that the contrast threshold for the detection of a visual signal in a noisy background can be considerably lower when binocular cues are available then when monocular cues only are present. Here, we investigated the occurrence of binocular unmasking with vertical interocular disparities. Subjects reported about the presence of Gabor signals in fields of two-dimensional broadband Gaussian noise surrounded by a frame of uniform noise. They saw these stimuli through a stereoscope; in all cases, the right-eye noise field was vertically displaced relative to the left one in either an upward or a downward direction, by up to 67.6'. In one condition, the right-eye signal was displaced by an amount equal to that of the noise, so that no opportunities for binocular unmasking existed; in the other, it appeared in exactly corresponding locations in the two fields--here, binocular disparities could be used to unmask the signal. Enhanced signal detectability, by up to 12.7 dB, was observed in the latter case for both directions of displacement, but only for displacements of 13.52' and only when the signal's orientation was horizontal. We argue that these effects result from the summation of monocular inputs carried out by linear binocular mechanisms.  相似文献   
992.
We interviewed a sample of 317 married women prior to a tubal sterilization (195) or a husband's vasectomy (122) and then reinterviewed them yearly for 5 years. Using these women's responses to six questions about their feelings and desires following sterilization, we fitted a latent-variable model of post-sterilization regret to the data by means of a linear structural equation analysis. The results confirmed our view that post-sterilization regret was not a simple psychological state but rather was a complex process with different, causally linked manifestations. This process began with a renewed interest in having a baby, proceeded to the development of negative feeling about the three decisions that lead to sterilization, and concluded with a desire to reverse the surgery. This sequence was affected by the negative, post-sterilization effects of the sterilization and by the Occurrence of divorce. Next, we identified the pre-sterilization predictors of six regret variables from our model by means of a series of linear regression analyses. The major pre-sterilization predictors of the regret process included being relatively young, ambivalence about future childbearing, negative attitudes toward sterilization, dominance of the decision making by the woman's husband, and conflict with her husband during decision making. Finally, we divided the sample into quintiles on the basis of their scores on a Pre-Sterilization Predictor Scale and assessed the performance of our predictor variables as indicators of risk of regret by determining the level of negative feelings toward sterilization in each quintile. The results confirm the discriminatory power of our predictors. The overall findings indicate a number of psychological and marital issues, the exploration of which might help counselors provide anticipatory and preventative services to couples seeking sterilization.  相似文献   
993.
Social influence processes affecting adolescent substance use   总被引:14,自引:0,他引:14  
Social influence is central to models of adolescent substance use. Nonetheless, researchers fail to delineate the various forms of social influence. A framework that distinguishes between active (explicit drug offers) and passive (social modeling and overestimation of friends' use) social pressure was tested. The effect of these processes on alcohol and cigarette use was examined with 526 seventh graders taking part in an alcohol prevention program. Hierarchical regression analyses demonstrated that pretest measures of alcohol use, offers, modeling, and overestimation each accounted for unique variance in posttest alcohol use. Similar results were obtained for cigarette smoking. The general model was not significantly different for boys and girls, or for prior users and prior nonusers, supporting the generalizability of the framework. Implications for intervention programs are discussed.  相似文献   
994.
995.
Twenty teachers each taught a male and a female student two different lessons. One of these lessons was in a stereotypically masculine domain (mechanics), the other in a stereotypically feminine domain (vocabulary). Judges viewed clips from the videotaped lessons and rated teachers' nonverbal behaviors. The students also rated their teachers on a variety of behavioral dimensions. The results showed that teachers exhibited more positive behavior toward the students for whose gender the material being taught was stereotypically appropriate. Similarly, teachers exhibited more negative behavior toward those students for whose gender the material being taught was considered stereotypically inappropriate. Additionally, teacher gender was shown to interact with the above-mentioned biased teaching behavior. Generally speaking, women teachers behaved in a less gender-biased way than did men teachers. It is suggested that these kinds of differential teaching behaviors may contribute to the differential performance of male and female students in traditionally gender-stereotyped academic domains.  相似文献   
996.
Children have difficulty learning to read alphabetic writing systems, in part, because they have difficulty segmenting spoken language into phonemes. Young children also have difficulty attending to the individual dimensions of visual objects. Thus, children's early difficulty in reading may be one sign of a general inability to selectively attend to the parts of any perceptual wholes. To explore this notion, children in kindergarten through fourth grade (Experiments 1, 3, and 4) and adults (Experiment 2) classified triads of spoken syllables and triads of visual objects. Classifying speech by common parts was positively related to reading and spelling ability (Experiments 1 and 4), but usually not to classifying visual stimuli by common parts under free classification instructions (Experiments 1 through 3). However, classification was more consistent across the visual and auditory modalities when the children were told to classify based on a shared constituent (Experiment 4). Regardless of instructions, performance on the visual tasks did not usually relate to reading and spelling skill. The ability to attend selectively to phonemes seems to be a "special" skill--one which may require specific experiences with language, such as those involved in learning to read an alphabetic writing system.  相似文献   
997.
Speed of word identification is important in the theories of reading proposed by La Berge and Samuels (1974) and Perfetti (1985), and is substantially correlated with reading skill. However, there is controversy about whether disabled readers have a speed deficit that is restricted to the identification of printed words, or if instead, they have a more general speed deficit in retrieving names of even single digits. To investigate this issue, poor and average readers (N = 43) in grade 2 were assessed on several indices of speed of digit and letter naming, using both continuous-list and discrete-trial methodologies. MANCOVA indicated clear effects of reader group on discrete-trial latencies, as well as an interaction between reader group and the speed with which to-be-named items were presented. A series of hierarchical regression analyses explored the amount of shared variance between various measures of digit naming speed and five indices of reading skill. Latency for word identification shares considerable variance with latency for digit naming, and, in general, accounts for the shared variance of naming speed and several other measures of reading skill. Naming speed contributed variance in reading skill. Naming speed contributed variance in reading skill independently of measures of phonological awareness.  相似文献   
998.
The purpose of this investigation was to explore sex and race discrimination in employment at the managerial level, with special focus on Black women.  相似文献   
999.
1000.
Masculinity (M) and femininity (F) were related to multiple dimensions of self-concept in 2 large studies. Androgyny theory predicts that M and F contribute positively to self-concept, but the effect of F has been nil in research using global self measures. Here, consistent with the new differentiated additive model, the relative contribution of M and F varied substantially, depending on the area of self-concept; F contributed more positively to self-concept facets that were more stereotypically feminine. Support for the model was consistent across self-responses and responses by significant others (Study 1) and across 5 age groups in early-to-middle adolescence (Study 2).  相似文献   
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