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931.
The role of perceived efficacy, parent support, and community involvement in the self-esteem and ethnic identity of 68 African-American male youth were investigated in this research. The results provided support for the distinctiveness of ethnic identity and self-esteem. A sense of mastery was positively associated with both self-esteem and ethnic identity. Parent support was associated with self-esteem, while community involvement and an appreciation of African-American heritage were positively related to ethnic identity. Implications for future research and the evaluation of prevention and support programs for youth are discussed.  相似文献   
932.
This paper presents a behavioral model which proposes that operants are organized and regulated into systems of responding. Multi-operant theory proposes that operants are organized into response systems that interact to adapt behavior to the complexities of the environment. The operant is the interaction between behavior and the environment which includes the conditions under which responses may occur, the class of behavior that is likely to be effective in producing outcomes, and the antecedent conditions that define the context of behavior. A central feature of this theory is that operants within a repertoire are organized into regulated systems of responding. The mechanisms of regulation are themselves operants that are learned and controlled by processes that are the same as those that govern more overt behavior. Operants stand in relationship to each other in coordinated response systems with some operants directly affecting and organizing the performance of other operants. An important implication of the systemic nature of behavioral repertoires is that bringing some aspect of a behavior class under control of new variables may demonstrate a spread throughout the entire operant system depending on past histories linking the classes.deceased  相似文献   
933.
934.
This article presents a theoretical argument to explain the way in which unemployed people react to and cope with threats to their identities that derive from perceptions ofstigma and low self-worth. It is argued here that strategies used by unemployed people to cope with such threats are influenced by whether the individuals categorize themselves as “unemployed” or adopt some other categorization (e.g., housewife, retired coal-miner). It is also proposed that the concept of self-categorization can be framed within Folkman and Lazarus’s (1980, 1985) coping model of distress in order to provide a more general framework for understanding these issues. The study reviews literature about stigma and coping with threatened identities with reference to these integrated frameworks, and concludes with a general model for predicting the way in which unemployed people self-categorize and cope with stigma and low self-esteem. This takes into account the role played by situational and individual factors, and suggests that individuals recategorize themselves in order to cope better during different phases of their unemployment.  相似文献   
935.
A compelling impression of movement, which is perceptually indistinguishable from a real displacement, can be elicited by patterns containing no spatially displaced elements. An apparent oscillation, w-movement, was generated by a stationary pattern containing a large number of horizontal pairs of spatially adjacent dots modulated in brightness. The observer’s task was to adjust the perceived amplitude of the w-motion to match the amplitude of a real oscillation. All of the data can be accounted for by a simple rule: If the relative change in the luminance,W = αL/L, between two adjacent stationary dots is kept constant, the distance over which these dots appeared to travel in space comprises a fixed fraction of the total distance by which they are separated. The apparent amplitude of the w-motion increases strictly in proportion with luminance contrast, provided that the contrast is represented in the motion-encoding system by a rapidly saturating compressive Weibull transformation. These findings can be explained in terms of bilocal motion encoders comparing two luminance modulations occurring at two different locations.  相似文献   
936.
This paper describes the use of a custom-configured computer-controlled firearms training simulator to measure perception response (reaction) time (RT) to a stimulus in which the degree of threat presented is a manipulable variable across trials. The computer records the number of frames of videotape traversed between the point of presentation of the threat in the video stimulus and the point at which the subject responds by drawing the firearm. For the purposes of data analysis, these frame-count measures are converted to RT measurements. Example data are presented that capture perception RT at both thedraw-stimulus and thefire-stimulus points in situations for which either only one threat or more than one threat exists. Other elements, such as degree of threat and accuracy of response, provide additional data.  相似文献   
937.
938.
The purpose of the present study was to compare the oculomotor behavior of readers scanning meaningful and meaningless materials. Four conditions were used—a normal-text-reading control condition, and three experimental conditions in which the amount of linguistic processing was reduced, either by presenting the subjects with repeated letter strings or by asking the subjects to search for a target letter in texts or letter strings. The results show that global eye-movement characteristics (such as saccade size and fixation duration), as well as local characteristics (such as word-skipping rate, landing site, refixation probability, and refixation position), are very similar in the four conditions. The finding that the eyes are capable of generating an autonomous oculomotor scanning strategy in the absence of any linguistic information to process argues in favor of the idea that such predetermined oculomotor strategies might be an important determinant of eye movements in reading.  相似文献   
939.
Enhancing possible selves in Mexican American students   总被引:3,自引:0,他引:3  
This project assessed the modifiability of possible selves in young Mexican American children. Three intervention conditions were compared in a pre- and posttest design: child-only intervention, parent and child intervention, and a no-intervention control. Following eight intervention sessions, children in the two intervention groups showed significant gains in understanding the characteristics associated with becoming a good student and in recognizing the value of education in bringing about future occupational goals. Children in the intervention conditions also reported greater interest in becoming a physician, judge, or pilot — occupations they had directly experienced during training. The parent intervention phase contributed little to augmenting the positive results attributable to the child intervention component.This research was conducted under the auspices of NIH Grant HD-24003. We wish to thank Maritza Robles and the staff of the Bilingual program of the South Bend, IN, Corporation for their support.  相似文献   
940.
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