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991.
Contrasting beliefs and attitudes held by sharecroppers and their landlord on a fazenda in Northeastern Brazil reveal a tendency to split one another into positively and negatively idealized images. Sharecroppers who ambivalently seek patronage construct good vs. bad landlords/patrons. The landlord, defensive about envy and hostility among sharecroppers, constructs good vs. bad tenants/workers. Theory from the Kleinian school of psychoanalysis concerning envy, splitting, and idealization provides a framework for interpreting ethnographic case materials.  相似文献   
992.
Although understanding of the subsistence patterns, service utilization, and HIV-risk behaviors of homeless youths and young adults is increasing, relatively little is known about the epidemiology of mental health problems in this group or the relationships between mental health problems and substance use. This study measured symptoms of depression, low self-esteem, ADHD, suicidality, self-injurious behavior (SIB), and drug and alcohol use disorder in a sample of homeless youth and young adults living in Hollywood, CA. Results indicated extremely high prevalences of mental health problems, as compared with corresponding rates of mental health problems found among housed youths in previous studies. Prevalence of mental health problems differed by age and ethnicity. African Americans were at lower risk of suicidal thoughts and SIB than were those of other ethnicities. Older respondents and females were at increased risk of depressive symptoms, and younger respondents were at increased risk of SIB. Previous history of sexual abuse and/or assault was associated with increased risk of suicidality and SIB. Risk factors for drug abuse disorder included ethnicity other than African American, homelessness for 1 year or more, suicidality, SIB, depressive symptoms, and low self-esteem. Risk factors for alcohol abuse disorder included male gender, white ethnicity, homelessness for 1 year or more, suicidality, and SIB. Extremely high rates of mental health problems and substance abuse disorders in this sample suggest the need for street-based and nontraditional mental health services targeted toward these youths and young adults.  相似文献   
993.
Abstract— The extent to which infants combine visual (i e, retinal position) and nonvisual (eye or head position) spatial information in planning saccades relates to the issue of what spatial frame or frames of reference influence early visually guided action. We explored this question by testing infants from 4 to 6 months of age on the double-step saccade paradigm, which has shown that adults combine visual and eye position information into an egocentric (head- or trunk-centered) representation of saccade target locations. In contrast, our results imply that infants depend on a simple retinocentric representation at age 4 months, but by 6 months use egocentric representations more often to control saccade planning. Shifts in the representation of visual space for this simple sensorimotor behavior may index maturation in cortical circuitry devoted to visual spatial processing in general.  相似文献   
994.
Syllogisms with or without negative terms are studied by using Gergonnes ideas. Soundness, completeness, and decidability results are given.  相似文献   
995.
The relationships between specific quantities and frequencies of alcohol, cigarette, and illicit substance use and substance use (SUD) and other psychiatric disorders were investigated among 1,285 randomly selected children and adolescents, aged 9 to 18, and their parents, from the Methods for the Epidemiology of Child and Adolescent Mental Disorders (MECA) Study. Logistic regressions indicated that daily cigarette smoking, weekly alcohol consumption, and any illicit substance use in the past year were each independently associated with an elevated likelihood of diagnosis with SUD and other psychiatric disorders (anxiety, mood, or disruptive behavior disorders), controlling for sociodemographic characteristics (age, gender, ethnicity, family income). The associations between the use of specific substances and specific psychiatric disorders varied as a function of gender.  相似文献   
996.
Acute angles frequently are overestimated, an effect that has been attributed to lateral inhibitory mechanisms. It can be derived from such theories that lengthening the arms of an angle should either reduce or not affect its judged subtense. However, in Experiments 1 and 2, it was found that angles with longer arms were judged larger. In Experiment 3, direct measures of anglearm orientation indicated that orientation contrast does not increase with angle-arm length, that it decreases with distance from the angle vertex, and that these effects are not averaged along the entire length of the arm. It follows that inhibitory mechanisms alone cannot explain why longer armed angles appear larger or why angle arms appear straight rather than bowed. It is suggested that a distinction is required between the orientation and the angular domains and that the latter judgments depend, at least partially, on the space or area within an angle. The fact that angles appear unbowed may reflect the fact that perceived orientation differences occur along an angle’s arm only when matches are made to small segments of the arm.  相似文献   
997.
Dreams and reality monitoring   总被引:1,自引:0,他引:1  
Experiment 1 tested the counterintuitive prediction that memories for one's own dreams should not be particularly easy to discriminate from memories for someone else's dreams. Pairs of people reported dreams to each other that they had either dreamed, read, or made up the night before. On a test requiring subjects to discriminate events they had reported from those reported by their partner, subjects had more difficulty with real dreams than with dreams they read or made up. Experiment 2 provided evidence that real dreams do not simply produce overall weaker memories; the deficit for dreams was eliminated with more time to respond and with more detailed cues. In addition, subjects' ratings of various characteristics of their memories (e.g., vividness, personal relevance) indicated that dreams were not generally weaker or impoverished. The results are interpreted within the framework for reality monitoring described by Johnson and Raye (1981): Memories for real dreams are proposed to be deficient in conscious cognitive operations that help identify the origin of information generated in a waking state. At the same time, real dreams are embedded in a network of supporting memories that can be drawn on for reality monitoring decisions under appropriate circumstances. Finally, a comparison of recognition and recall indicated that dreams may leave persisting memories that are difficult to access via free recall.  相似文献   
998.
The generality of Spearman's hypothesis that varying differences between whites and blacks on various tests of mental ability are correlated with their g-loadings was tested by analyzing group data from the Hawaii Family Study of Cognition. Data from the three largest ethnic groups tested in the Hawaii Study (Americans of Japanese, Chinese or European ancestry; total N = 5333) were subjected to a principal-component analysis and the first principal component was used as a measure of g. Ethnic group and generation (parent-offspring) differences on 15 tests of specific cognitive abilities were then correlated with their first principal-component loadings. In general, correlations between ethnic group differences and g-loadings are smaller than those recently reported for white-black differences by Jensen (1983); however, those between generation differences and g-loadings are larger. Ethnic group differences on first principal-component scores in the Hawaii Study are less than parent-offspring differences; thus, the correlation between group differences on tests of mental ability and their g-loadings may be a function of the magnitude of the group difference for general mental ability. Because a group difference on g requires group differences on tests which load on g, an observed group difference in general mental ability may necessarily result in a correlation between group differences on individual tests and their g-loadings.  相似文献   
999.
1000.
Support for averaging processes in information integration has relied on experimental designs in which the amount of information to be integrated was varied. The usual interpretation is that subjects balance the values of the various stimuli presented on a given trial. An alternative interpretation is that subjects may use their perceptions of the relationship between stimulus dimensions to infer the value of missing information. In the present study, subjects were asked to rate their expected satisfaction with purchases of ground beef on the basis of quality and/or price information. The responses of some subjects appeared to be based on the inference that high prices imply high quality and low prices imply low quality when no quality information is given. Other subjects appeared to assign a constant value to missing information. An averaging model that incorporates inferred as well as presented stimulus values is proposed.  相似文献   
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