EMG activity as a function of the performer's focus of attention

In previous studies of attentional focus effects, investigators have measured performance outcome. Here, however, the authors used electromyography (EMG) to determine whether difference between external and internal foci would also be manifested at the neuromuscular level. In 2 experiments, participants (N=11, Experiment 1; N=12, Experiment 2) performed biceps curls while focusing on the movements of the curl bar (external focus) or on their arms (internal focus). In Experiment 1, movements were performed faster under external than under internal focus conditions. Also, integrated EMG (iEMG) activity was reduced when performers adopted an external focus. In Experiment 2, movement time was controlled through the use of a metronome, and iEMG activity was again reduced under external focus conditions. Those findings are in line with the constrained action hypothesis (G. Wulf, N. McNevin, & C. H. Shea, 2001), according to which an external focus promotes the use of more automatic control processes.     

Reciprocal influences of attentional focus on postural and suprapostural task performance

The authors examined the influence that attentional focus on either a postural or a suprapostural task had on the performance of each task. Participants (N = 32) stood on an inflated rubber disk and held a pole horizontally. All participants performed under 4 attentional focus conditions: external (disk) or internal (feet) focus on the postural task, and external (pole) or internal (hands) focus on the suprapostural task. Compared with internal focuses, external focuses on either task resulted in similar and reduced postural sway. Response frequency on each task increased when participants focused on the respective task. Finally, an external focus on either task produced higher frequencies of responding on the suprapostural task. The authors conclude that suprapostural task goals have a stronger influence on postural control than vice versa, reflecting the propensity of the motor system to optimize control processes on the basis of the desired movement effect.     

Transitions to and from asymmetrical gait patterns

Asymmetrical gait patterns such as the gallop provide insight into the complexity of human locomotion. The nature of spontaneous (e.g., walk-run), quasi-spontaneous (e.g., gallop-walk), and intentional (e.g., walk-gallop) transitions was analyzed in 2 ways in the present study. In Analysis 1, the authors used step-wise regression to associate 10 physical characteristics with gait transitions. Transition predictability was moderate; thigh length best predicted 3 of 6 transitions. In Analysis 2, the dynamic characteristics of transitions (order parameters, phase shifts, multistability, and critical fluctuations) were described; those characteristics existed for all transition types. The results of the analyses suggest that intentional transitions are less biomechanically predictable than are spontaneous transitions and that transitions between gait pairs (e.g., walk-gallop and gallop-walk), regardless of velocity direction, have more in common than do transitions requiring specific intention.     

School-year employment among high school students: effects on academic, social, and physical functioning

This study describes the effects of different weekly work intensity levels on adolescent functioning in a sample of 3,083 high school students in rural South Texas, where economically disadvantaged and Hispanic youth are heavily represented. Anonymous surveys were conducted in 10th- and 12th-grade students' classrooms in 1995. The following effects were associated with long hours of weekly employment during the school year: (1) decreased performance/engagement in school and satisfaction with amount of leisure time, and (2) increased health risk behaviors and psychological stress. The effects of school-year work on academic factors and health behaviors differed by grade, but not by race/ethnicity, parent education, or race/ethnicity and parent education considered together. It was concluded that parents and professionals should continue to monitor the number of weekly hours that students work during the school year.     

"Too late": ambivalence about motherhood, choice, and time

This paper explores a particular constellation of fantasies and defenses that in some women leads to the delay of childbearing. Destructive wishes towards the woman's own womb and her mother's lead to behaviors that sabotage fertility and pregnancy. These wishes and behaviors meet up with an unconscious belief in and commitment to time standing still, and with cultural tropes and trends that obscure intrapsychic conflicts and denials about motherhood, aging, and time. Analysis, like childbearing, is constrained by the reality of time, and the complex untangling and connecting of these three not obviously related threads may not occur until it is, for the woman who wants a child, too late.     

Psychology,population, and reproductive behavior

This special section on international perspectives in psychology focuses on population issues and reproductive behavior across national and cultural boundaries, emphasizing the responsibility of psychologists and colleagues in related disciplines to generate and communicate culturally mindful findings likely to shape public health policy and improve human well-being. After considering the historical and policy context, it highlights internationally collaborative research projects in the Czech Republic, Egypt, Mexico, and the United States that address reproductive behavior, women's roles and status, responsible parenthood, and abortion legislation in terms of cultural context, gender equity, the needs of adolescents, and public health policy. The articles illustrate the importance of the cultural context within which psychological research is conducted and how psychology can be informed by international perspectives.     

Shyness: relationship to social phobia and other psychiatric disorders

The relationship between shyness, social phobia and other psychiatric disorders was examined. The prevalence of social phobia was significantly higher among shy persons (18%) compared with non-shy persons (3%). However, the majority of shy individuals (82%) were not socially phobic. A significant and positive correlation was found between the severity of shyness and the presence of social phobia, but the data suggest that social phobia is not merely severe shyness. Social phobia was also positively and moderately correlated with introversion and neuroticism. Thus, shy persons with social phobia were shyer, more introverted, and more neurotic than other shy people, but none of these factors was sufficient to distinguish shy persons with social phobia from those without social phobia. The proportion of the shy group with psychiatric diagnoses other than social phobia was significantly higher than among the non-shy group, indicating that various diagnostic categories are prominent among the shy. The results are discussed in terms of the overlap in shyness and social phobia and the relationship of shyness to other psychiatric diagnoses and personality dimensions.     

Effects of daily events on mood states in major depressive disorder

Major depressive disorder (MDD) is characterized by high negative affect (NA) and low positive affect (PA), but little is known about emotional reactivity in daily life. The authors used experience sampling methodology to investigate changes in NA and PA following minor daily events in MDD compared with healthy participants. Contrary to expectation, MDD participants did not report more frequent negative events, although they did report fewer positive events. Multilevel regression showed that both NA and PA responses to negative events were blunted in the MDD group, whereas responses to positive events were enhanced. NA responses to negative events persisted longer in MDD participants. Depressed participants with a positive family history or longer current episodes showed relatively greater NA responses to negative events.     

Latent growth curve analyses of accelerating decline in cognitive abilities in late adulthood

Latent growth models were applied to data from the Swedish Adoption/Twin Study of Aging to discover if the rate of change in cognitive performance increased from middle age to later adulthood. The sample included 590 participants aged 44 to 88 years at first measurement. Data were gathered at 2 follow-up occasions at intervals of 3 years. Cognitive ability was assessed through 11 tests that tapped crystallized, fluid, memory, and spatial abilities and perceptual speed. Results indicated stability for measures of crystallized ability, linear age changes for many cognitive abilities, and a significant acceleration in linear decline after age 65 for measures with a large speed component. Gender differences were found only in mean level, not in rate of decline.