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71.
Performance maintained under concurrent schedules consisting of a variable-interval avoidance component and a variable-interval positive-reinforcement component was studied in three human subjects using points exchangeable for money as the reinforcer. The rate of responding in the avoidance component increased, and the rate of responding in the positive-reinforcement component declined, as a function of the frequency of point-losses avoided in the avoidance component. The performance of all three subjects conformed to equations proposed by Herrnstein to describe behavior in concurrent schedules. The logarithms of the ratios of the response rates in the two components, and the logarithms of the ratios of the times spent in the two components, were linearly related to the logarithms of the ratios of the frequency of loss avoidance in the avoidance component to the frequency of reinforcement in the positive-reinforcement component. When a changeover delay of 5.0 sec was imposed, the slopes of the linear functions were close to 1.0 in the case of two subjects, whereas the third subject exhibited significant undermatching. For two subjects the changeover delay was then reduced to 2.0 sec; in both cases the slopes of the linear functions were lower than under the 5.0-sec condition. One subject participated in a third phase, in which no changeover delay was imposed; there was a further reduction in the slopes of the linear functions.  相似文献   
72.
This research examined gender differences in orientations toward autonomous and social achievement. Three independent samples of subjects (total N= 359 males and 574 females) completed measures of achievement orientation (including Strumpfer's [1975] Autonomous Achievement Values and Social Achievement Values scales) and relevant cognitive, affective, and behavioral variables. Correlational and factor analyses clearly identified distinct autonomous and social achievement factors for both men and women in each of the samples. Examination of the correlates of achievement orientation indicated that whereas an autonomous achievement orientation is similarly expressed in males and females, there are considerable sex differences in the expression of an orientation toward social achievement. In particular, a social achievement orientation was associated with concerns over social approval and responsiveness to social influence among males, but was generally unrelated to these factors among females. Findings are discussed in terms of several recent hypotheses concerning the effects of sex role norms on the development and expression of achievement needs in men and women.  相似文献   
73.
A battery of measures was used to assess conflict between mothers and young adolescents (females and males, 11 to 15 years of age). Two groups of families, one composed of a distressed clinical sample (N = 38), the other a nondistressed normative sample (N = 40), participated. The assessment battery included retrospective judgments, frequency estimates, self-monitored home recording, and tape-recorded discussion of a home problem. Content of assessment measures tapped aspects of parental control, decisionmaking, self-reported interaction behavior, arguments, interaction behavior rated by independent “blind” observers, frequency and anger-intensity of specific problematic issues, and perceptions of positive and negative behaviors of the other family member. Based on univariate analyses, 21 of the 26 defined variables discriminated significantly in the predicted direction. Maternal and adolescent reports of behavior and independent ratings of tape-recorded interaction emerged as strong and consistent discriminators. Stepwise multivariate discriminant analysis provided successful classification of 100% of the families based on the inclusion of nine variables. In a cross-validation sample, 84% of the families were correctly classified. Implications for systematic outcome research as well as clinical application are discussed.  相似文献   
74.
In one component of a multiple schedule of food presentation, monkeys acquired a different four-response chain each session by responding sequentially on three keys in the presence of four geometric forms (learning). In the other component, the four-response chain was the same each session (performance). Both d-amphetamine and cocaine, at the higher doses, disrupted the behavior in the learning component; the overall response rate decreased, the overall accuracy was impaired (i.e., percent errors increased), and there was less within-session error reduction. The performance component was generally less sensitive than the learning component to the disruptive effects of both drugs on rate and accuracy. After pre-feeding or during an extended session, the response rate decreased in both components, but accuracy was generally unaffected. When the four discriminative stimuli in both components were removed, the behavior was disrupted to a greater extent in the performance component. The disruptive effects of both drugs on behavior in the learning component were attenuated when the drugs were administered during the session after the response chain had been acquired. It was concluded that the greater sensitivity of the learning component to disruptive drug effects is related to the relatively weak stimulus control and/or the lower rate of reinforcement associated with that component.  相似文献   
75.
The physical movement and social characteristics of effeminate behavior-problem, referred boys (N=13)were compared with those of normal boys (N=25)and boys (N=12)referred for nongender problems. Parent reports, observer ratings, and videotapes were collected in a series of structured tasks. As expected, mothers described gender-problem sons as much more feminine than the other two groups in interests, activities, and mannerisms. Gender-problem sons were also seen as relatively inactive and introverted. Further, they were non-significantly lower than the clinical control boys in perceived behavior problems, but both groups had marginally more problems than the normal boys. Gender-problem and clinical control boys both showed more body constriction than normal boys in ratings of a videotaped interview. They also both showed less ideal ball-throw form than normal boys on a set of variables scored with slow-motion video. However, in a set of behaviors directly rated in the various tasks, the gender-problem boys gave a uniquely general impression of uncoordination. The groups did not differ on seven additional variables.The research was supported in part by USPHS Grant MH17072. The authors are indebted to the more than two dozen research staff members who contributed many essential services at various stages of the project, to the families who generously participated, to the clinicians who referred their clients to our project, and to Marion Hee for computational assistance.  相似文献   
76.
Salt taste detection: an R-index approach to signal-detection measurements   总被引:1,自引:0,他引:1  
The R-index approach to the signal-detection P(A) index of sensitivity was used to measure taste sensitivity to NaCl solutions. The R-index is the predicted probability of the correct choice of a signal, for a given signal-noise pair. For flow-wise and sipwise presentation, R-indices did not fluctuate significantly, provided subjects could not see the stimuli yet to be presented, indicating a lack of systematic sensitivity drift. The simultaneous measurement of more than one signal strength with reference to a common noise stimulus was seen to be a viable and sensitive procedure. Comparison of flow-wise and sipwise presentation of stimuli using R-indices, indicated that the former elicited greater subject sensitivity to NaCl taste.  相似文献   
77.
The incidences of sex-role outcome within homosexual and heterosexual male and female young adult samples were compared using a fourfold typology (both masculine and feminine, masculine, feminine, neither masculine nor feminine). Sex-role identity disparities between the female groups were more clear-cut; the most striking difference was the high incidence of masculinity (60%) within the homosexual female group. No significant differences for males were found, although a trend was noted toward higher incidence of femininity and lower incidence of masculinity in homosexuals. The second purpose of the study was to search for possible developmental antecedents to heterosexual deficit in unselected college samples. The same key pattern of psychometric indices was identified for males and females. Low heterosexuality and the closest approximation to the modal sex-role identity among homosexuals of their sex were found in females primarily identified with masculine fathers and low in role consistency and in males primarily identified with feminine mothers and low in role consistency.  相似文献   
78.
This study examined differences in vocational maturity of women across different levels of internal-external control and typical versus atypical vocational choice. It was predicted that internally controlled women would have higher vocational maturity scores than externally controlled women; women who make atypical vocational choices would have higher vocational maturity scores than women who make typical choices. Data from the Attitude Scale of Crites' Career Maturity Inventory, MacDonald and Tseng's I-E Scale, and dichotomized ratings of typical versus atypical vocational choice were obtained from 179 freshmen to senior female student volunteers in a large New England university. Analysis of variance indicated that internally controlled women had significantly higher vocational maturity than externally controlled women (p <. 01); no differences were found in vocational maturity between those making typical or atypical vocational choices; the lowest level of vocational maturity was found for externally controlled females making atypical vocational choices. Implications of these findings for counseling are discussed.  相似文献   
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