Gender differences in leg stiffness and stiffness recruitment strategy during two-legged hopping

The authors compared leg stiffness (K(VERT)), muscle activation, and joint movement patterns between 11 men and 10 women during hopping. Physically active and healthy men and women performed continuous 2-legged hopping at their preferred rate and at 3.0 Hz. Compared with men, women demonstrated decreased K(VERT); however, after the authors normalized for body mass, gender differences in K(VERT) were eliminated. In comparison with men, women also demonstrated increased quadriceps and soleus activity, as well as greater quadriceps-to-hamstrings coactivation ratios. There were no significant gender differences for joint movement patterns (p>.05). The relationship between the observed gender differences in muscle recruitment and the increased risk of anterior cruciate ligament injury in women requires further study.     

Rightward biases in free-viewing visual bisection tasks: implications for leftward responses biases on similar tasks

Neurologically normal individuals exhibit strong leftward response biases during free-viewing perceptual judgments of brightness, quantity, and size. When participants view two mirror-reversed objects and they are forced to choose which object appears darker, more numerous, or larger, the stimulus with the relevant feature on the left side is chosen 60-75% of the time. This effect could be influenced by inaccurate judgments of the true centre-point of the objects being compared. In order to test this possibility, 10 participants completed three visual bisection tasks on stimuli known to elicit strong leftward response biases. Participants were monitored using a remote eye-tracking device and instructed to stare at the subjective midpoint of objects presented on a computer screen. Although it was predicted that bisection errors would deviate to the left of centre (as is the case in the line bisection literature), the opposite effect was found. Significant rightward bisection errors were evident on two of the three tasks, and the leftward biases seen during forced-choice tasks could be the result of misjudgments to the right of centre on these same tasks.     

Asian and Pacific Island American students' acculturation and etiology beliefs about typical counseling presenting problems

Asian American Pacific Island college students (N = 93) completed measures of acculturation and mental health worldview, in the form of beliefs about the likely causes of 24 typical counseling presenting problems. A criterion sample of 27 staff from 2 university counseling centers reported their beliefs about the most likely cause of the same 24 problems for a typical client. A response similarity index was calculated, with higher scores reflecting greater similarity between student and counselor mental health worldviews. Results suggest that higher acculturation was associated with greater level of match between the students' etiology beliefs and those of counselors. The greatest differences were observed for serious personal problems, whereas there was more belief convergence about causes of academic problems.     

Signal-detection analyses of conditional discrimination and delayed matching-to-sample performance

Quantitative analyses of stimulus control and reinforcer control in conditional discriminations and delayed matching-to-sample procedures often encounter a problem; it is not clear how to analyze data when subjects have not made errors. The present article examines two common methods for overcoming this problem. Monte Carlo simulations of performance demonstrated that both methods introduced systematic deviations into the results, and that there were genuine risks of drawing misleading conclusions concerning behavioral models of signal detection and animal short-term memory.     

Identifying shared environmental contributions to early substance use: the respective roles of peers and parents

Although behavior genetic studies have suggested that early substance use is primarily environmentally mediated, no study has sought to identify the specific sources of environmental variance. Using data obtained from multiple informants, this study assessed the contributions of peer deviance and parent-child relationship problems to substance use in 14-year-old male and female twins (N = 1,403) drawn from the Minnesota Twin Family Study (MTFS). All three phenotypes were influenced primarily by shared environmental variance (average c(2) =.51), as was the overlap among them. Moreover, peer deviance and parent-child relationship problems accounted for approximately 77% of the variance in early substance use. Findings also indicated that peer deviance, but not parent-child relationship problems, accounted uniquely for variance in early substance use.     

The time course and significance of cannabis withdrawal

Withdrawal symptoms following cessation of heavy cannabis (marijuana) use have been reported, yet their time course and clinical importance have not been established. A 50-day outpatient study assessed 18 marijuana users during a 5-day smoking-as-usual phase followed by a 45-day abstinence phase. Parallel assessment of 12 ex-users was obtained. A withdrawal pattern was observed for aggression, anger, anxiety, decreased appetite, decreased body weight, irritability, restlessness, shakiness, sleep problems, and stomach pain. Onset typically occurred between Days 1-3, peak effects between Days 2-6, and most effects lasted 4-14 days. The magnitude and time course of these effects appeared comparable to tobacco and other withdrawal syndromes. These effects likely contribute to the development of dependence and difficulty stopping use. Criteria for cannabis withdrawal are proposed.     

Customers' perceptions of salespersons' orientation and susceptibility to salespersons' influence

This study examined correlations of scores for salespersons' and customers' orientation, as indicated by a modified Salesperson Orientation-Customer Orientation scale, with self-reported consumers' susceptibility to salespersons' information, recommendations, and relational influence. Vehicle purchasers provided 508 useable survey responses. Correlations for customers' perceptions of both salespersons' orientation (-.39 and -.21) and customers' orientation (.39 and .24) were related to self-reports of susceptibility to salespersons' information and relational influence.     

Terminal decline and cognitive performance in very old age: does cause of death matter?

Cross-sectional differences and longitudinal changes in cognitive functioning in relation to mortality across a 7-year follow-up period, with 3 times of measurement, were examined in a population-based sample of very old adults. The authors also sought to determine whether cause of death (cerebro/cardiovascular disease [CVD]; non-CVD) modified the magnitude of mortality-related cognitive deficits. Cognitive performance was indexed by tests of general cognitive ability, episodic memory, primary memory, verbal fluency, and visuospatial ability. Results indicated cross-sectional differences on all domains of functioning, with persons who would die within 3 years after baseline testing performing more poorly. Longitudinally, greater decrements were observed on all domains for persons who would die after the first follow-up period, as compared with survivors. Cause of death failed to modify the magnitude of the cross-sectional and longitudinal deficits. The pattern of results point to the general nature of this phenomenon.     

Field Independence and Change Agent Correlation in Emerging Communities of Irian Jaya,Indonesia

Communities that are limited by oral traditions find theological truths communicated by missions a challenge to understand. Currently, linguists work in many of these minority language groups in order to create vital written languages and produce various literature titles that include the Scriptures. Development of a writing system requires indigenous language assistants who are adept in drawing meaning from unfamiliar cultural paradigms and accurately articulating them. Empirical studies in cognitive style conducted among the minority language groups of Irian Jaya, Indonesia show a correlation between field independence (a dimension of cognitive style) and the ability to grasp abstract linguistic concepts. The Brantley/Larsen Test was developed to identify language assistants, also known as change agents, in a culturally appropriate manner for Irian Jaya. Furthermore, this study suggests that the church would benefit from community lay counselors who manifest field independence, which indicates comprehension of abstract and complex linguistic notions found in Scriptures.Indonesia as Organizational Consultant;     

What People Want From Their Professionals: Attitudes Toward Decision‐making Strategies

Attitudes toward four types of decision‐making strategies—clinical/fully rational, clinical/heuristic, actuarial/fully rational, and actuarial/heuristic—were examined across three studies. In Study 1, undergraduate students were split randomly between legal and medical decision‐making scenarios and asked to rate each strategy in terms of the following: (i) preference; (ii) accuracy; (iii) fairness; (iv) ethicalness; and (v) its perceived similarity to the strategies used by actual legal and medical professionals to make decisions. Studies 2 and 3 extended Study 1 by using a more relevant scenario and a community sample, respectively. Across the three studies, the clinical/fully rational strategy tended to be rated the highest across all attitudinal judgments, whereas the actuarial/heuristic strategy tended to receive the lowest ratings. Considering the two strategy‐differentiating factors separately, clinically based strategies tended to be rated higher than actuarially based strategies, and fully rational strategies were always rated higher than heuristic‐based strategies. The potential implications of the results for professionals' and those affected by their decisions are discussed. Copyright © 2011 John Wiley & Sons, Ltd.