Social Comparison,the Threat of AIDS,and Adolescent Condom Use1

This study tested hypotheses from social comparison theory about adolescent condom use. Questionnaires were administered to 457 twelfth-grade students (284 sexually active). Three different operationalizations of social comparison were used—comparative ratings, affiliative preferences, and derogation; each produced different results. Low condom users who felt threatened by AIDS made more downward comparative ratings regarding condom use than did unthreatened low users. In contrast, low users preferred upward affiliations with high users. Adolescents with higher self-esteem derogated adolescents with AIDS less as threat increased. Adolescents with lower self-esteem who made downward comparative ratings were more satisfied with their own past condom use. Satisfied low condom users were less likely to intend condom use in the future. The results provide evidence that downward comparison may act indirectly to deter behavioral change.     

Psychology at a crossroads

The current state of psychology is examined from the perspective that academic psychology and the private practice of psychology are faced with threats of their own obsolescence. Factors contributing to tensions in the discipline, as well as some hopeful signs, are reviewed. Three linked proposals are presented for the long-term resolution of these problems. An appropriate setting and a comprehensive model for graduate education are suggested. The third proposal concerns changes in our view of ourselves. A restoration of a sense of community is seen as a precondition for any constructive action.     

Understanding movement control in infants through the analysis of limb intersegmental dynamics

One important component in the understanding of the control of limb movements is the way in which the central nervous system accounts for joint forces and torques that may be generated not only by muscle actions but by gravity and by passive reactions related to the movements of limb segments. In this study, we asked how the neuromotor system of young infants controls a range of active and passive forces to produce a stereotypic, nonintentional movement. We specifically analyzed limb intersegmental dynamics in spontaneous, cyclic leg movements (kicking) of varying intensity in supine 3-month-old human infants. Using inverse dynamics, we calculated the contributions of active (muscular) and passive (motion-dependent and gravitational) torque components at the hip, knee, and ankle joints from three-dimensional limb kinematics. To calculate joint torques, accurate estimates were needed of the limb's anthropometric parameters, which we determined using a model of the human body. Our analysis of limb intersegmental dynamics explicitly quantified the complex interplay of active and passive forces producing the simple, involuntary kicking movements commonly seen in 3-month-old infants. our results revealed that in nonvigorous kicks, hip joint reversal was the result of an extensor torque due to gravity, opposed by the combined flexor effect of the muscle torque and the total motion-dependent torque. The total motion-dependent torque increased as a hip flexor torque in more vigorous kicks; an extensor muscle torque was necessary to counteract the flexor influences of the total motion-dependent torque and, in the case of large ranges of motion, a flexor gravity torque as well. Thus, with changing passive torque influences due to motions of the linked segments, the muscle torques were adjusted to produce a net torque to reverse the kicking motion. As a consequence, despite considerable heterogeneity in the intensity, range of motion, coordination, and movement context of each kick, smooth trajectories resulted from the muscle torque, counteracting and complementing not only gravity but also the motion-dependent torques generated by movement of the linked segments.     

Size of critical band in infants, children, and adults

Masked thresholds at two signal frequencies (0.8 and 4 kHz) were obtained from listeners aged 6.5 months, 2 years, 5 years, and 20.5 years in the presence of constant spectrum level, narrowband maskers of differing bandwidths. Consistent with the classical results of Fletcher (1940), masked threshold for all age groups increased with bandwidth up to a critical width, beyond which further increases in bandwidth were ineffective in increasing threshold. These critical widths (estimates of critical band size) did not change substantially with age (critical widths for infants were no more than 50% larger than those of adults) despite substantial changes in masked thresholds with age. Thus, contrary to previous claims, changes in auditory filter width cannot account for developmental changes in masked or absolute thresholds.     

Diagnostic implications of McCarthy scale general cognitive index/binet IQ discrepancies for low-socioeconomic-status preschool children

This study compared McCarthy Scale General Cognitive Index (GCI) and Stanford-Binet IQ discrepancies for both normal and handicapped preschool children of low socioeconomic status (SES). Both tests were administered in counter-balanced order to a total of 70 children. The results of these comparisons yielded a significant positive relationship between GCI and IQ, as well as a significant discrepancy between the two scores, favoring IQ, of a relatively small magnitude (3.9 points). There were significant discrepancies favoring IQ for the subgroups of learning-disabled, speech-impaired, and mentally retarded, those for all but mentally retarded being of relatively small magnitude; thus, the learning-disabled group was not uniquely characterized by a large discrepancy. In contrast to results consistently favoring IQ over GCI, when age groups were compared, the younger, 3 year olds, showed the reverse, though nonsignificant, trend.     

Stress-coping-support in rural communities: A model for primary prevention

Conclusion Because of the relatively small and homogeneous population in rural communities, community-wide prevention efforts are often more manageable than in urban areas. Community needs and resources can be identified more easily, and the feasibility of different interventions can be assessed more readily.To guide the rural prevention agent in developing community programs, the stress-coping-support framework has been proposed here. The value of this model is that it delineates the aspects of community life that must be assessed, and it outlines several different intervention goals. The model in its most general form proposes that prevention activities should reduce stress, increase coping, and build support. While this model can be applied to any community or target group, the framework has been elaborated here to address the unique physical, occupational, and societal characteristics of rural communities.Although some of the issues in applying this model to rural, as opposed to urban, areas have been pointed out here, the variation among rural communities has not been addressed fully. The different types of rural communities, e.g., the mining town, the isolated farmlands, the Indian reservation, have unique characteristics which may determine whether a proposed prevention program is needed, feasible, and effective.It is hoped that rural practitioners, long sensitive to the need for prevention, will use this model to devise additional prevention directions and to generate useful and culturally syntonic programs for their communities.