Role of proprioceptive information in movement programming and control in 5 to 11-year old children

The role of proprioceptive inputs in the control of goal-directed movements was examined, by means of the tendon vibration technique, in 5 to 11-year old children performing a serial pointing task. Children pointed, with movements of various amplitudes and at various positions, by alternating wrist flexions and extensions. Tendon vibration was applied to both agonist and antagonist muscles to perturb relevant muscular proprioceptive inputs during the static or dynamic phase of the task, i.e., during stops on targets or during movement execution. Constant and variable amplitude errors as well as constant position error were evaluated. Vibratory perturbation applied during movement execution resulted in a similar reduction in movement amplitude, yielding an increased constant error in all age groups and a systematic position error in the direction of the movement starting point. Perturbing proprioception during static phases preceding movement resulted in an age-related increase in the variable amplitude error, which was maximal in 5-year old children performing extension movements. The results were interpreted in terms of the use of proprioceptive information in the feedforward and feedback based components of movement control in children. In particular, the results indicated (1) developmental changes in the relative weighting of each component, (2) an increased capacity to move from one strategy to the other, depending on the availability of information, and (3) developmental changes from an alternated to an integrated control of amplitude and position in serial pointing.     

Racial Stereotypes and Gender in Context: African Americans at Predominantly Black and Predominantly White Colleges

In this study, relationships among stereotype expectations, gender, and academic self-concept and performance of African American students in predominantly White and predominantly Black college contexts were examined. Stereotype expectations are students' perceptions of biased treatment and evaluation within their major classroom settings (SE). Findings indicated that students' majors were related to stereotype expectations, as well as to their academic competence. Our results also provide evidence of gender and institutional interactions in the relationships between stereotype expectations and academic outcomes. Results are discussed in terms of the need to examine issues of race and gender in the academic experiences of African Americans, as well as how their specific school and classroom contexts may influence their experiences.     

The Evolution of Gendered Political Behavior: Contributions from Feminist Evolutionists

This commentary discusses Rebecca Hannagan’s article “Gendered Political Behavior: A Darwinian Feminist Approach,” an interdisciplinary examination of how human female social and political behaviors are unique and have impacted the evolution of human societies. She reexamines the anthropological literature on egalitarian foraging societies to focus on female autonomy and leadership, and connects women’s evolved skills with their contemporary leadership experiences. As Hannagan’s work demonstrates, Darwinian feminists challenge sexist stereotypes from a variety of sub-disciplines that use evolutionary perspectives, build upon and expand the earlier ground-breaking work of other feminist evolutionists, and blaze new trails using the latest technology and models to gain further understanding of human behavior that will help promote greater equality and opportunities for women.     

The Temporal Dimension of Social Episodes: Position Effect in Time Judgments of Unfilled Intervals

An experiment was conducted to test the prediction, derived from field theory, that unfilled intervals at the core of a social episode (in-process) are perceived to last longer than unfilled intervals at the beginning (preprocess) or toward the end of the social episode (postprocess). As expected, individuals who judged in-process unfilled intervals overestimated their duration and judged them to last longer than individuals who judged preprocess or postprocess unfilled intervals. Moreover, this finding was observed in both immediate and delayed time duration estimates, and the overestimation effect for in-process intervals was stronger in the remote than in the immediate estimates. Relations to prior research on delays in services and implications for the management of services are discussed.     

Subjective valuation and asymmetrical motivational systems: implications of scope insensitivity for decision making

Studies using the Iowa Gambling Task have revealed individual differences in performance on the task. In this study, we tested the hypothesis that approach and avoidance motivations influence decision making through the process of subjective valuation. We examined the implications of a high sensitivity to gains or losses from two perspectives which we labeled scalar multiplication and valuation by feeling. Using two versions of the Iowa Gambling Task, we find evidence supporting the view that asymmetry in the systems regulating approach and avoidance leads to systematic biases that translate to differences in performance. Specifically, we find that high sensitivity in the Behavioral Activation System (BAS) translates to valuation by feeling and insensitivity to scope in the domain of gains, while high sensitivity in the Behavioral Inhibition System (BIS) translates to valuation by feeling and insensitivity to scope in the domain of losses. The basis for these findings is discussed. Copyright © 2007 John Wiley & Sons, Ltd.     

What is a Leather Iron or a Bird Phone? Using Conceptual Combinations to Generate and Understand New Product Concepts

This article introduces the framework of conceptual combinations, which underlies the creative ability to combine existing concepts to create new ones. Using this framework, two creative processes are identified, namely, (a) property mapping (PM), which entails combining concepts by transferring a property from one concept to another (e.g., shape in the case of notebook computers); and (b) relation linking (RL), which entails linking the two combining concepts by a thematic relation (e.g., the “locative” relation in desktop computers). The effect of these processes on the comprehension of new product concepts is investigated in two experimental studies. In Study 1 it is shown that novel products created by RL are easier to interpret than the ones created by PM. In Study 2 it is found that new products combining concepts from different super‐ordinate categories are more likely interpreted by RL, and are easier to comprehend than the ones from the same super‐ordinate category, which use PM. The theoretical and managerial implications of using conceptual combinations in the context of new product ideation are discussed.     

Information processing and movement optimization during development: kinematics of cyclical pointing in 5- to 11-year-old children

The authors studied the development of movement control in speed-accuracy tradeoff conditions in children aged 5-11 years and in adults performing cyclical pointings. Twelve difficulty levels (IDs), ranging from 2 to 6.58 bits, were defined (P. M. Fitts, 1954). Peak and time to peak velocity, acceleration, and deceleration, and acceleration profiles as a function of hand position (Hooke's portraits) were analyzed. Movement time decreased with age and was less affected by ID. Peak velocity and acceleration increased, acceleration and deceleration were decreasingly time consuming, and movement profiles turned to increased harmonicity with age and task easiness. Nevertheless, the developmental trends differed between parameters. Gain in velocity seemed chiefly dependent on improved muscular cooperation patterns before 7 years of age and on improved information processing from age 7 onward; achievement of an optimized strategy in the speed-accuracy tradeoff occurred at age 11 years.     

Sex Differences in the Presentation of Chronic Low Back Pain

Sex differences in 351 patients with chronic low back pain were examined. Biological, psychological, and psychosocial factors were considered. Sex differences in adaptive functioning were consistent with traditional gender roles. Significant interactions were found for sex and employment status, and sex and marital status. Retired women reported more pain and less activity than retired men. Retired men reported the least pain of any group. Outdoor work and social activities show opposite within–group patterns for men and women when stratified by employment status. Marriage was associated with more household work for women and less for men. The financial and social contexts of employment status and marriage are different for men and women. Results suggest the treatment of women with chronic low back pain requires attention to work in the home and the financial and social context of work outside the home.     

The content and structure of laypeople's concept of pleasure

Five studies were conducted to map the content and structure of laypeople's conceptions of pleasure. Instances of the pleasure concept collected in Study 1 consisted predominantly of objects, events or persons described as sources of pleasure. Content analysis suggested that the pleasure category, like emotional response categories, might be formed at an implicit level where various pleasure antecedents are grouped based on common phenomenological qualities of the affective experience. Studies 2 and 3a showed that the pleasure category possesses a graded structure and fuzzy boundaries. Results further revealed that, either when explicitly presented with labels (Study 3b) or left to their own implicit categories during a sorting task (Study 4), laypeople represented pleasure as a hierarchical concept in which differentiated pleasure types (i.e., intellectual, emotional, social and physical) were subsumed under a higher level unitary form of pleasure. In this structure, unitary and differentiated pleasures shared a set of common affective qualities but were also distinguishable by unique and distinctive affective characteristics (Study 5). Ties to prior theories of pleasure and implications for decision making and behavioural research are discussed.