Adaptation in Visuomanual Tracking Depends on Intact Proprioception

The role of arm proprioception in motor learning was investigated in experiments in which, by moving the arm, subjects followed the motion of a target displayed on a monitor screen. Adaptive capabilities were tested in visuomanual tracking tasks following alterations in the relationship between the observer's actual arm movement and visual feedback of the arm movement given by a cursor motion on the screen. Tracking performance and adaptive changes, measured in terms of spatiotemporal error, tracking trajectory curvature, and spatial gain, were compared in 7 control subjects (CSs) and in 1 deafferented subject (DS). CSs adapted appropriately to altered visuomanual relationships; those changes were present in trials immediately after restoration of normal scaling. In contrast, although the DS modified his tracking strategy from trial to trial according to the altered conditions, he did not show plastic changes in internal visuomanual scaling. Like the results of prismatic adaptation experiments, the present results suggest that arm proprioception contributes to the plastic changes that follow alterations in the scaling of visuomanual gain.     

A Controlled Pilot-Outcome Study of Sensory Integration (SI) in the Treatment of Complex Adaptation to Traumatic Stress

This study tested whether sensory integration (SI) treatment combined with psychotherapy would improve symptom outcome over psychotherapy alone in the treatment of complex posttraumatic stress, as measured by the Disorders of Extreme Stress Not Otherwise Specified (DESNOS) clinical construct in a group of 10 adult patients with histories of childhood abuse. DESNOS symptoms were assessed at three time periods (T1, baseline; T2, after experimental group SI treatment; and T3, after wait-list control group SI treatment) using the Structured Interview for Disorders of Extreme Stress (SIDES). The Sensory Learning Program? (SLP), developed by the Sensory Learning Institute of Boulder, Colorado, was used as the SI treatment modality. Results indicated significant differential improvement for the group treated with SLP in SIDES Total Score (T1/T2 and T2/T3), Self Perception (T1/T2 and T2/T3), Affect Regulation (T2/T3), and Alterations in Meaning (T1/T2).     

Prism Exposure Aftereffects and Direct Effects for Different Movement and Feedback Times

The effects of movement time and time to visual feedback (feedback time) on prism exposure aftereffects and direct effects were studied. In Experiment 1, the participants' (N = 60) pointing limb became visible early in the movement (.2-s feedback time, and eye-head aftereffects increased with increasing movement time (.5 to 3.0 s), but larger hand-head aftereffects showed little change. Direct effects (terminal error during exposure) showed near-perfect compensation for the prismatic displacement (11.4 diopters) when movement time was short but decreasing compensation with longer movement times. In Experiment 2, participants' (N = 48) eye-head aftereffects increased and their larger hand-head aftereffects decreased with increasing movement time (2.0 and 3.0 s), especially when feedback time increased (.25 and 1.5 s). Direct effects showed increasing overcompensation for longer movement and feedback times. Those results suggest that aftereffects and direct effects measure distinct adaptive processes, namely, spatial realignment and strategic control, respectively. Differences in movement and feedback times evoke different eye -hand coordination strategies and consequent direct effects. Realignment aftereffects also depend upon the coordination strategy deployed, but not all strategies support realignment. Moreover, realignment is transparent to strategic control and, when added to strategic correction, may produce nonadaptive performance.     

Motivational and cognitive determinants of control during conflict processing

Previous studies suggest that both reward anticipation and expected or experienced conflicts activate cognitive control. The present study investigated how these factors interact during conflict processing. In two experiments, participants performed a variant of the Stroop task, receiving performance-dependent monetary rewards in some blocks. In addition, we manipulated the level of conflict-triggered reactive and expectancy-driven proactive control: In Experiment 1, we compared the Stroop effect after previously congruent and incongruent trials to examine the conflict adaptation effect (reactive control). We found that the level of motivation did not interact with conflict adaptation. In Experiment 2, we varied the proportion of congruent and incongruent trials to manipulate conflict expectancy (proactive control). The data suggest the effects of motivation to be less pronounced under conditions of high conflict expectancy. We conclude that the interaction of motivation with cognitive determinants of control depends on whether these activate proactive or reactive control processes.     

In- and out-of-school peer groups of immigrant youths

Multiethnic societies typically aim to have immigrant and native youths mix and be friends, preferably in all contexts in which they spend time. Schools and neighbourhoods are the two settings where youths spend the most time with peers during adolescence. The present study explored the in- and out-of-school peer groups of 174 immigrant junior high school pupils (Mean age = 14.39) who attended an integrated school but lived in a segregated neighbourhood. A person-oriented approach was used and cluster analyses were conducted both within and across the two settings. The results show that youths mostly have the same kind of friendship formations in both settings, regardless of the ethnic composition of each setting. In terms of adaptation, the results consistently show that for boys, having only immigrant friends is related to problematic adaptation in both settings. No relationship between peer formations and adaptation was found for girls. The study highlights the importance of considering gender and viewing youths as embedded in systems of multiple settings, in order to achieve true integration.     

Adaptation to a Nonlinear Visuomotor Amplitude Transformation With Continuous and Terminal Visual Feedback

The control of a cursor on a computer monitor offers a simple means of exploring the limits of the plasticity of human visuomotor coordination. The authors explored the boundary conditions for adaptation to nonlinear visuomotor amplitude transformations. The authors hypothesized that only with terminal visual feedback during practice, but not with continuous visual feedback, humans might develop an internal model of the nonlinear visuomotor amplitude transformation. Thus, 2 groups were engaged in a sensorimotor adaptation task receiving either continuous or terminal visual feedback during the practice phase. In contrast to expectations, adaptive shifts and aftereffects observed in visual open-loop tests were linearly related to target amplitudes for both groups. Although the 2 feedback groups did not differ with respect to adaptive shifts and aftereffects, terminal visual feedback resulted in stable visual open-loop performance for an extended period, whereas movement errors increased after continuous visual feedback during practice. The benefit of continuous visual feedback, on the other hand, was faster closed-loop performance, indicating an optimization of visual closed-loop control.     

Predictable Mispredictions in the Context of Physical Activity and Sport: A Review

Theoretical models and research that aim to identify antecedents of participation in physical activities or sport can measure antecedents of physical activity behaviour through instruments that involve subjective predictions. In this article, we argue that such instruments may not reflect physical activity experiences or behaviour accurately because people are not very good predictors of future states. Additionally, we propose that mispredictions may be predictable because they are “caused” by tendencies to neglect processes related to hedonic adaptation and competing alternatives. We also suggest that it may be possible to improve measurement of antecedents through methods that focus respondents' attention on factors that cause mispredictions or through experiential sampling methods.     

The Dimensionality of Right-Wing Authoritarianism: Lessons from the Dilemma between Theory and Measurement

The RWA Scale ( Altemeyer, 1981 , 1988 , 1996 ) is commonly regarded as the best measure of right-wing authoritarianism. The one-dimensional instrument assesses the covariation of three attitudinal clusters: authoritarian submission, authoritarian aggression, and conventionalism. The incongruence between the implicit conceptual dimensionality on the one hand and methodological operationalization on the other makes room for discussion about whether it would be advantageous to measure the 3 facets of RWA separately. I rely on three arguments: (1) confirmatory factor analyses showing that three-dimensional scales fit the data better than the conventional one-dimensional practice; (2) the dimensions showing a considerable interdimension discrepancy in their capability to explain validation criteria; and (3) the dimensions showing an intradimensional discrepancy which is dependent upon the research question. The argumentation is illustrated by empirical evidence from several Web-based studies among German Internet users.     

初一学生人格特征、学习适应性与学习成绩关系的研究

以《中学生个性测验量表》和《学习适应性测验量表》为研究工具,以320名初一学生为被试,探讨初一学生个性因素、学习适应性与学习成绩的关系。结果发现,初一学生的个性特征、学习适应性与学习成绩都存在一定的相关关系;初一学生的个性因素中自控及情绪性因素和智力性因素对其学习成绩具有更好的预测作用,学习适应性因素中学习期望和家庭环境对其学习成绩具有较好的预测作用;研究同时认为,个性特征与学习适应性对初一学生学习成绩的影响可能是非常有限的。