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841.
The inhibition of return of visual attention based on stimulus color was examined in three experiments. In the first experiment, a discrete trial paradigm showed that subjects were slower to detect a color patch if the color matched that of a patch presented earlier in the same location. Experiment 2 showed that the inhibition only occurs if a neutral, nontarget distractor color is presented between presentation of the initial color cue and the subsequent target patch—explaining the previous failures to detect the phenomenon. Experiment 3 extended the results to a different combination of colors. Taken together, the results have important implications for the processing of stimulus attributes such as spatial location and color, and for the conditions necessary for producing inhibition of return.  相似文献   
842.
A mother's (prenatal) wish for a girl has, at times, been implicated as an etiological factor for boyhood femininity or its DSM-III-R diagnostic equivalent, the Gender Identity Disorder of Childhood. In one sample of 52 feminine and 52 nonclinical control boys from Los Angeles, the proportion of mothers who recalled a wish for a girl during the pregnancy did not differ significantly between groups (26.9% vs. 19.2%, respectively); however, in both groups, the maternal wish for a girl was significantly more common in sibships in which all of the proband's older siblings were male. In a second sample of 103 feminine boys from Toronto, the maternal wish for a girl was significantly higher than that found in the Los Angeles sample (43.7% vs. 26.9%), but a control group was not available; as in the Los Angeles sample, the maternal wish for a girl was significantly more common in sibships in which all of the proband's older siblings were male. Implications of these findings for further study of maternal influences on boyhood femininity are discussed.  相似文献   
843.
Aggressivity, inattention, hyperactivity, and impulsivity are cardinal dimensions of externalizing behavior problems of childhood. They are diagnostic and clinical features of childhood disorders, and are thought to be linked to the subsequent development of adult disorders such as substance abuse (SA). Little is known, however, about the convergent and discriminant validity of these four constructs. We used multiple measures to develop indices of aggressivity, inattention, hyperactivity, and impulsivity in a sample of 10- to 12-year-old boys (N=183) with and without a family history of SA. Data were taken from mother reports, child reports, teacher reports, and laboratory tasks. The study aims were (1) to test the convergent and discriminant validity of aggressivity, inattention, hyperactivity, and impulsivity; (2) to examine whether the data were consistent with a model specifying the four constructs as indicators of one superordinate factor; and (3) to differentiate boys with and without a family history of SA in construct scores. The results supported the convergent and discriminant validity of the four constructs. Although discriminable, the constructs covaried strongly and were consistent with a model specifying them as indicators of a single superordinate factor. Boys with a family history of substance abuse scored higher than control boys on aggressivity, inattention, and impulsivity scores, but the groups did not differ on hyperactivity scores. The results are discussed in terms of the role of childhood behavior problems in vulnerability to SA.This work was supported by the National Institute on Drug Abuse grant No. DA 05605.  相似文献   
844.
This study examined the mediating role of anxiety in the self-reports of somatic complaints in 96 depressed adolescent inpatients. Sixty-four subjects with major depressive episodes and comorbid anxiety disorders (MDE-A) determined from the Diagnostic Interview for Children and Adolescents-Revised (DICA-R) reported significantly more somatic complaints than 32 adolescents having major depressive episodes without comorbid anxiety (MDE). An analysis of covariance demonstrated that, with anxiety symptoms controlled, MDE and MDE-A groups did not differ significantly in somatic complaints. A hierarchical multiple-regression analysis revealed that, with demographic and anxiety symptoms controlled, depressive symptoms did not contribute to the explanation or prediction of somatic complaints. The results suggest that anxious, but not depressive symptoms, are independently associated with somatic complaints. The results are discussed in light of new affective models of psychopathology.  相似文献   
845.
Clancy and Hoyer (1993) have recently investigated the effects of domain-specific expertise and hemispheric asymmetry on detecting featural differences in visual patterns. Based on the pattern of reaction time results, they concluded that there is a left-hemisphere advantage for making difficult, domain-relevant visual discriminations in skilled experts but not in unskilled control subjects. However, response accuracy data from the same experiment contradict their conclusions about the relationship of skill to the pattern of hemispheric asymmetry and favor an alternative interpretation in terms of the specific aspects of visual information needed to make different types of discrimination.  相似文献   
846.
Doress-Worters  Paula B. 《Sex roles》1994,31(9-10):597-616
Sex Roles - Research on the effect of multiple roles on women's well-being has focused almost exclusively on the employment and child rearing roles of younger women, and has overlooked the...  相似文献   
847.
848.
These three papers present a quite diverse and complementary set of answers to the question, "Why Sexuality Matters to Philosophy." They show the ways in which sexuality as an issue may be of interest to philosophers working on a wide range of questions. The theme of sexuality appears as both subject matter and context for the development of scientific theories of human behavior, as a pervasive dimension of the representation of everyday life, and as a social phenomenon raising important questions bearing on the implications of equal citizenship for persons of different genders and sexualities. Sexuality reveals itself as implicated in epistemology and philosophy of science, aesthetics and ethics, political philosophy and jurisprudence. Sexuality as a subject matter provides rich examples for extending the treatment of quite traditional problems. At the same time, by identifying sexuality as a fundamental human phenomenon, fraught with normative implications and closely linked to emotional and bodily life, these papers show how thinking about sexuality may also act to unsettle and redefine certain important areas of philosophical inquiry.  相似文献   
849.
An apparatus was developed to study social reinforcement in the rat. Four Long-Evans female rats were trained to press a lever via shaping, with the reinforcer being access to a castrated male rat. Responding under a fixed-ratio schedule and in extinction was also observed. Social access was found to be an effective reinforcer. When social reinforcement was compared with food reinforcement under similar conditions of deprivation and reinforcer duration, no significant differences were observed.  相似文献   
850.
Male Siamese fighting fish, Betta splendens, swam through a ring in an aquarium, breaking a photocell beam and initiating an unsignaled, resetting delay interval. Following delays of 0 s, 10 s, or 25 s, a 15-s mirror presentation released an aggressive display by the fish. Swimming through the ring increased in the absence of either a period of acclimatization to the reinforcer (analogous to magazine training when appetitive reinforcers are used) or explicit training of the response by the experimenters. Response rates were a decreasing function of delay duration. Other fish exposed to a schedule of response-independent mirror presentations failed to acquire and maintain the response. The results demonstrate the robustness and generality of the phenomenon of response acquisition with delayed reinforcement. They further qualify earlier observations about behavioral mechanisms involved in the phenomenon.  相似文献   
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