Delayed temporal discrimination in pigeons: A comparison of two procedures

A within-subjects comparison was made of pigeons' performance on two temporal discrimination procedures that were signaled by differently colored keylight samples. During stimulus trials, a peck on the key displaying a slanted line was reinforced following short keylight samples, and a peck on the key displaying a horizontal line was reinforced following long keylight samples, regardless of the location of the stimuli on those two choice keys. During position trials, a peck on the left key was reinforced following short keylight samples and a peck on the right key was reinforced following long keylight samples, regardless of which line stimulus appeared on the correct key. Thus, on stimulus trials, the correct choice key could not be discriminated prior to the presentation of the test stimuli, whereas on position trials, the correct choice key could be discriminated during the presentation of the sample stimulus. During Phase 1, with a 0-s delay between sample and choice stimuli, discrimination learning was faster on position trials than on stimulus trials for all 4 birds. During Phase 2, 0-, 0.5-, and 1.0-s delays produced differential loss of stimulus control under the two tasks for 2 birds. Response patterns during the delay intervals provided some evidence for differential mediation of the two delayed discriminations. These between-task differences suggest that the same processes may not mediate performance in each.     

Individual differences and measures of aggression in laboratory studies

After inducing hostility toward a confederate by threatening subjects' self-esteem, subjects were then given the opportunity either to deliver shocks (Experiment 1) or to withhold rewards (Experiment 2) from their confederate. Physiological measures were taken prior to the hostility induction, shortly after the induction and, finally, after the opportunity to aggress. Measures of individual differences relating to aggressive behavior were also considered. While the experimental manipulation was the best predictor in the ‘withholding rewards’ condition, measures of dissipation-rumination tendencies and emotional vulnerability were the best predictors in the ‘shock administration’ condition. In both conditions, systolic blood pressure seemed to reflect differences in arousal as a function of the hostility induction procedure, while subjects in the withhold rewards procedure also showed a decrease in systolic pressure after having an opportunity to aggress toward the confederate. It was concluded that not only is the withholding of rewards a more ethically acceptable procedure than shock administration, but it is also more likely to reflect experimental rather than individual difference affects.     

It's not who you are but who you're with: Self-Confidence in achievement settings

This study examined the effects of two social cues on women's and men's self-confidence: the sex and performance of another in an achievement setting. Before trying to solve 60 anagrams, women expected to perform more poorly than men. In addition, both sexes expected to perform more poorly when paired with a male confederate than when paired with a female confederate. The effect of the partner's sex showed up in anagram performance: people with a female partner solved more anagrams than people with a male partner. The effect of subject's sex on performance was unexpected: women solved more anagrams than men. After the task, sex differences in self-confidence disappeared; neither sex of subject nor sex of partner influenced self-confidence. The partner's performance, however, had a strong effect on everyone: people were less self-confident if they had worked with a high-scoring partner. The pattern of results suggests that sex-of-subject differences in self-confidence, while important, are less powerful than the effects wielded by the sex of others in achievement settings.     

The influence of individual and family characteristics upon career aspirations of girls during childhood and adolescence

The term pioneer is used for girls aspiring to male-dominated careers. This longitudinal study assesses the career choices of 68 middle-class girls during childhood (8–13 years, Phase I) and again during adolescence (13–18 years, Phase II), and investigates the relation between pioneering career choice and personal and family characteristics. Subjects were originally selected for exposure vs nonexposure to exogenous hormones during pregnancy. In childhood, pioneers were somewhat older, were more often persistent tomboys, had higher IQs, and had parents with higher educational attainment. In adolescence, paternal education was the only variable that showed the same relation to career choice. Adolescent girls who had wanted to get married at the time of the childhood assessment were now less likely to choose pioneering careers. Adolescent pioneers also had higher educational aspirations than nonpioneers and less likely anticipated being married within ten years than nonpioneers. A number of statistically borderline relationships were also observed: pioneers had somewhat fewer older brothers than nonpioneers, less often came from homes in which traditional femininity was stressed, and more frequently had mothers who had worked outside the home throughout their daughters' school years than mothers of nonpioneers. Prenatal exposure to exogenous sex hormones was not related to career choice during either childhood or adolescence.     

The differential importance of weight and body image among college men and women

Among a sample of American college students, body image and the degree of desired weight change were associated with academic self-rankings, with social and psychological well-being, and with the development of eating difficulties. The effects of body image and desired weight change on eating disorders were generally found to be greater for women than for men, and their effects on student self-rankings of academic ability, social, and psychological traits were more pervasive for women than for men. The less attractive a woman perceived herself to be and the more weight she wanted to lose, the greater was her overall sense of academic, social, and psychological impairment. Women who had poor body images and who desired to lose weight were more likely to report eating difficulties.     

Ethnic identity, self-esteem, and occupational aspirations of Indian and Anglo-Saxon British adolescents

A questionnaire monitoring occupational aspiration, ethnic identification, adolescent experience, and self-esteem was administered to a large sample of Indian and Anglo-Saxon British male and female adolescents attending school in the West Midlands. The relationship between these variables and differences between the four groups were consistent with predictions derived from the social identity approach to intergroup relations and group behaviour (Tajfel & Turner, 1979). Indian males were found to possess a social mobility belief structure that mediates high occupational aspirations and keeness to marry out of their ethnic group. In contrast, Indian females were found to possess a social change belief structure associated with acceptance of the status quo and lower aspirations. Males and Anglo-Saxons reported higher self-esteem than females or Indians. The adolescent experience findings were less clear, but were consistent with the general interpretation of the data that the differences in intersex relations and gender-related experiences are contingent on ethnicity.     

Learning and motivation: Computer simulations of the Rescorla-Wagner,Solomon-Corbit,and Schull models

A suite of programs is described for simulating the Rescorla-Wagner (1972) model of associative learning, the Solomon and Corbit (1974) opponent-process theory, and Schull’s (1979) extension of the latter. The programs are written for the Commodore 64 computer.     

Containment theory and juvenile delinquency: a reevaluation through factor analysis

All seven variables of containment theory were operationalized for questionnaires. Data were collected from 677 adolescents in a variety of high schools and correctional institutions, and divided into categories by race and sex. Factor analysis indicated that the structure of the relationships among the seven containment variables and delinquency was substantially different among black females.