论儿童心理发展的动力及其机制

本文依据马克思主义的唯物史观和唯物辩证法原理,从儿童的实际社会生活过程出发,运用系统方法论证了儿童心理发展的动力是主客体之间的结构性矛盾,而由“主体──活动──客体”三项格式构成的反馈回路系统则是心理发生发展的动力场。本文还运用儿童心理发展的控制论模型,从活动的机能性方面探讨了同化和顺应之间的平衡化动力机制,揭示了主客体之间矛盾运动的原理和过程;平衡化机制是受社会文化历史的发展规律支配的。     

Polanyi's Finalism

Although Michael Polanyi's model of science and his construal of the nature of the real are usually thought to be congenial to religion and although Polanyi himself says that "the stage on which we thus resume our full intellectual powers is borrowed from the Christian scheme of Fall and Redemption" (Polanyi 1958, 324), theologians have given little attention to the model of God he presents. The metaphysical and theological vision unfolded in part 4 of Personal Knowledge is a thoughtful alternative to materialist versions of neo-Darwinism and provides a platform for revisiting four long-standing controversies at the interface of science and religion: whether life and mind can be completely specified in terms of physical analysis, whether nature can be adequately understood without appeal to final causes, whether natural selection adequately explains life's diverse forms, and whether knowledge can be fully objectified. Through an exploration of Polanyi's contribution to these discussions, we undertake to show not only that his treatment of God as a cosmic field is strikingly original but also that in reinstating activity as a metaphysical category, he reconstructs our understanding of our creaturely hope and calling.     

Occupational conditions and workers' sense of community: Variations by gender and race

The literature is reviewed to define a sense of community in the workplace and to identify factors that may foster it. A model is developed and estimated with survey data from a culturally diverse sample of men and women performing lower-level jobs at a medium-sized manufacturing firm. Results of regression analyses are reported that correct for sample selection bias resulting from the lower response rates of minority workers. Findings suggest that well-designed jobs and supportive workplace relationships and policies are important in explaining workers' sense of community, defined as workers' perceptions of mutual commitment between employee and employer. Informal sources of support play a larger role in explaining men's sense of community, while formal sources of support are more important in explaining women's sense of community. Findings further suggest that African American workers, especially women, have a difficult time experiencing a sense of community at work. The authors thank the employees of Fel-Pro for their participation in this study and Melissa Roderick, Michael Sosin, and anonymous reviewers for their thoughtful comments. This research was funded by the Fel-Pro/Mecklenberger Foundation and the Lois and Samuel Silberman Fund.     

Force and rate relations in responding during variable-interval reinforcement

Four rats responded on one-minute variable-interval schedules with several variations in peak-force of response required for food reinforcement. Measures of peak force and rate were taken for the responses, which were the downward exertions of force against a static force-transducing operandum. The analysis distinguished responses, a generic class of measured behavior, from criterion responses, an operationally specified subclass required for reinforcement. Absolute rate of response showed no systematic change, but the rate of responses meeting a newly required criterion of peak-force invariably increased through changes in the absolute rate of response, the relative-frequency distributions of peak force, or some combination of both. The relative frequency of responses meeting an elevated force criterion during variable-interval reinforcement exceeded that maintained with the same criterion with continuous reinforcement. The requirement of more effortful responding for reinforcement does not necessarily reduce response rate. Conformity of the behavior to the requirement for reinforcement is the salient effect.     

Examination of the PC-PTSD in previously deployed Air Force Medical Service personnel

This study assessed the performance of the PC-PTSD in diagnosing postdeployment posttraumatic stress disorder (PTSD) in a cohort of Air Force Medical Services personnel (N = 18,530). The prevalence of PTSD in the cohort was 5.18% based on medical record data. The area under the receiver operating characteristic curve was 0.69, indicating poor classification accuracy. Sensitivity was 47.55%, specificity was 90.68%, positive predictive value was 21.79%, and negative predictive value was 96.94%. The positive and negative likelihood ratios were 5.10 and 0.58, respectively. Several risk factors were found to be associated with a diagnosis of postdeployment PTSD: being a nurse, being enlisted in the medical service career field, being enlisted in the mental health service career field, those over age 30, being a member of the Active Duty service component, and having one’s first deployment be to Iraq. Being an officer was found to be a protective characteristic. These factors could potentially improve screening for PTSD among Air Force healthcare personnel.     

Comparison of tongue muscle characteristics of preterm and full term infants during nutritive and nonnutritive sucking

Background

Independent oral feeding requires coordination of suck, swallow and breathe and the lingual musculature plays a significant role in this coordinative action. However, clinical benchmarks of lingual function fundamental to successful feeding have not been explored.

Aims

The present study tests our model for quantifying infant lingual force and size and compares the muscle measures of interest in two cohorts: healthy full-term infants (FT) (N = 5) and healthy preterm infants (PT) (N = 6).

Method

Using an instrumented pacifier and bottle nipple, we determined the resultant compressive forces applied to the nipple by the tongue during nutritive (NS) and nonnutritive sucking (NNS). Muscle size was estimated from measures of posterior tongue thickness using ultrasonography.

Results

After controlling for weight and post menstrual age, statistically significant differences were found between FT and PT infants beginning to feed for NNS frequency and NS tongue force. Clinically significant differences were detected for NNS tongue force and posterior tongue thickness. Additionally, PT infants demonstrated a significant difference in mean tongue force between NS and NNS and FT infants did not. FT infants demonstrated a significant difference in mean frequency between NS and NNS and PT infants did not. Linear regression indicated that mean posterior tongue thickness alone predicted 55% of the variance in NS force.

Conclusions

Results demonstrate the feasibility of our approach and suggest that infant tongue muscle characteristics necessary for successful feeding differ between healthy full term infants and preterm infants who are beginning oral feeding.     

Exchange‐based communication training may not consistently facilitate communication in the absence of the requested item

The role of stimulus presence on spontaneous communication was assessed with 3 participants in a nonconcurrent multiple baseline with embedded reversals design. Participants were taught to request 2 highly preferred items. Once mastery criterion was met, test sessions were conducted with stimuli either visible or absent from the room, and request rate was measured. For 2 participants, training produced requests in both the presence and absence of the stimulus. For one participant, however, the presence of the stimulus was necessary to evoke the response. Results suggest that teaching individuals to request items when they are present may not consistently lead to requests when those items are absent.     

An examination of lower limb asymmetry in ankle isometric force control

While asymmetries have been observed between the dominant and non-dominant legs, it is unclear whether they have different abilities in isometric force control (IFC). The purpose of this study was to compare ankle IFC between the legs. IFC is important for stabilization rather than object manipulation, and people typically use their non-dominant leg for stabilization tasks. Additionally, studies suggested that a limb can better acquire a motor task when the control mechanism of the task is related to what the limb is specialized for. We hypothesized that the non-dominant leg would better (1) control ankle IFC with speed and accuracy, and (2) acquire an ankle IFC skill through direct learning and transfer of learning. Two participant groups practiced an IFC task using either their dominant or non-dominant ankle. In a virtual environment, subjects moved a cursor to hit 24 targets in a maze by adjusting the direction and magnitude of ankle isometric force with speed (measured by the time required to hit all targets or movement time) and accuracy (number of collisions to a maze wall). Both groups demonstrated similar movement time and accuracy between the dominant and non-dominant limbs before practicing the task. After practice, both groups showed improvement in both variables on both the practiced and non-practiced sides (p < .01), but no between-group difference was detected in the degree of improvement on each side. The ability to control and acquire the IFC skill was similar between the legs, which did not support the brain is lateralized for ankle IFC.     

Impact of Tactile Sensation on Dexterity: A Cross-Sectional Study of Patients With Impaired Hand Function After Stroke

The authors sought to explore the impact of tactile sensation on manual dexterity and the validity of the strength-dexterity test in subjects with chronic impairments after stroke in a cross-sectional study of 24 patients with impaired hand function after stroke. Dexterity was assessed by the strength-dexterity test, Box and Blocks, and Nine-Hole Peg Test, and the ABILHAND questionnaire. Sensation was measured by pinprick, cotton-wool, graphesthesia, and 2-point discrimination tests. Sensation in the paretic hand had strong association with paretic hand performance in the strength-dexterity test and Nine-Hole Peg Test and explained 13% of the variance. Sensation in the nonparetic hand was associated with the results of the ABILHAND questionnaire. Among sensory tests, 2-point discrimination had the strongest association with dexterity tests. No significant correlations between sensation, pinch force, and dexterity tests were found for the nonparetic hand. The strength-dexterity test exhibited strong correlations with the other dexterity measures and with pinch force. There is an association between tactile sensation and dexterous performance in the paretic hand; activity level performance is associated with sensation in the nonparetic hand. The study supports the validity of the strength-dexterity test when applied in subjects in the chronic stage after stroke.     

Force and Directional Force Modulation Effects on Accuracy and Variability in Low-Level Pinch Force Tracking

The authors investigated how varying the required low-level forces and the direction of force change affect accuracy and variability of force production in a cyclic isometric pinch force tracking task. Eighteen healthy right-handed adult volunteers performed the tracking task over 3 different force ranges. Root mean square error and coefficient of variation were higher at lower force levels and during minimum reversals compared with maximum reversals. Overall, the thumb showed greater root mean square error and coefficient of variation scores than did the index finger during maximum reversals, but not during minimum reversals. The observed impaired performance during minimum reversals might originate from history-dependent mechanisms of force production and highly coupled 2-digit performance.