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991.
The aim of this research is to show the impact of linguistic (the feminine inflexion was audible or not) and cognitive (the complexity of the task in which the agreement is realized) factors about the acquisition and the use of adjectival gender inflexions in written French. In this perspective, we compared the production of the mark of the agreement in three tasks not mobilizing the same levels of linguistic treatment: transcribe sentences under dictation, recall sentences presented orally, and produce two sentences ending with an adjective from a syntactical priming. The results show that the systematic application of the adjectival agreement in gender is not totally mastered at the end of primary. Besides, the use of the adjectival gender inflexions is more difficult when the written inflexion is mute. Finally, the children forgot more the gender inflexion in written production task than in a dictate or recall task. These results are interpreted within the framework of a functional approach of language production. 相似文献
992.
This research captures the diversity of family patterns among gifted adolescents (IQ ≥ 130). Data on the perceived parental's support and investment in schooling, family relationships and sociobiographic characteristics were collected by questionnaire from 255 French junior high school gifted students (48 girls, 207 boys), aged 9 to 15 (M = 12.5; SD = 1.51). A hierarchical cluster analysis highlights the existence of four types differentiated, thereby going against a standardized and stereotypical representation of this population. 相似文献
993.
Objective
Variability in infant sleep and negative affective behavior (NAB) is a developmental phenomenon that has long been of interest to researchers and clinicians. However, analyses and delineation of such temporal patterns were often limited to basic statistical approaches, which may prevent adequate identification of meaningful variation within these patterns. Modern statistical procedures such as additive models may detect specific patterns of temporal variation in infant behavior more effectively.Method
Hundred and twenty-one mothers were asked to record different behaviors of their 4–44 weeks old healthy infants by diaries for three days consecutively. Circadian patterns as well as individual trajectories and day-to-day variability of infant sleep and NAB were modeled with generalized linear models (GLMs) including a linear and quadratic polynomial for time, a GLM with a polynomial of the 8th order, a GLM with a harmonic function, a generalized linear mixed model (GLMM) with a polynomial of the 8th order, a generalized additive model, and a generalized additive mixed model (GAMM).Results
The semi-parametric model GAMM was found to fit the data of infant sleep better than any other parametric model used. GLMM with a polynomial of the 8th order and GAMM modeled temporal patterns of infant NAB equally well, although the GLMM exhibited a slightly better model fit while GAMM was easier to interpret. Besides the well-known evening clustering in infant NAB we found a significant second peak in NAB around midday that was not affected by the constant decline in the amounts of NAB across the 3-day study period.Conclusion
Using advanced statistical procedures (GAMM and GLMM) even small variations and phenomena in infant behavior can be reliably detected. Future studies investigating variability and temporal patterns in infant variables may benefit from these statistical approaches. 相似文献994.
To maximize swimming speed athletes copy fish undulatory swimming during the underwater period after start and turn. The anatomical limitations may lead to deviations and may enforce compensating strategies. This has been investigated by analyzing the kinematics of two national female swimmers while swimming in a still water pool. Additionally, the flow around and behind the swimmers was measured with the aid of time-resolved particle image velocimetry (TR-2D-PIV). As compared to fish, the swimmers used undulatory waves characterized by much higher Strouhal numbers but very similar amplitude distributions along the body and Froude efficiencies. Vortices generated in the region of strongly flexing joints are suitable to be used pedally to enhance propulsion (vortex re-capturing). Complementing studies using numerical and technical modeling will help us to probe the efficiency of observed mechanisms and further improvements of the human strategy. 相似文献
995.
Humans have unique abilities in using tools. The skilled and goal-directed use of a tool implies that processes of motor control can be adjusted to the transformation of the movement of a part of the body into the movement of the effective part of the tool. A common example is the transformation of a hand movement in the motion of a cursor on a computer monitor. In part the adjustments to such transformations are implicit, that is, without conscious awareness of the novel transformation and the appropriate change of one’s own movements. However, the adjustments can also be explicit and intentional. We review a series of experiments which show that implicit and explicit adjustments to a novel visuo-motor gain are additive. This finding suggests that the processes which generate different types of adjustment are functionally independent. In a second series of experiments it turned out that at older adult age explicit adjustments to novel visuo-motor transformations are impaired, whereas implicit adjustments remain unaffected across working age. 相似文献
996.
R.C. Schmidt Paula Fitzpatrick Robert Caron Joanna Mergeche 《Human movement science》2011,30(5):834-845
Recently there has been much interest in social coordination of motor movements, or as it is referred to by some researchers, joint action. This paper reviews the cognitive perspective’s common coding/mirror neuron theory of joint action, describes some of its limitations and then presents the behavioral dynamics perspective as an alternative way of understanding social motor coordination. In particular, behavioral dynamics’ ability to explain the temporal coordination of interacting individuals is detailed. Two experiments are then described that demonstrate how dynamical processes of synchronization are apparent in the coordination underlying everyday joint actions such as martial art exercises, hand-clapping games, and conversations. The import of this evidence is that emergent dynamic patterns such as synchronization are the behavioral order that any neural substrate supporting joint action (e.g., mirror systems) would have to sustain. 相似文献
997.
Jenni OG Chaouch A Locatelli I Thoeni I Diezi M Werner H Caflisch J Rousson V 《Human movement science》2011,30(6):1272-1282
This study investigates the intra-individual stability of the speed of several motor tasks and the intensity of associated movements in 256 children (131 girls, 125 boys) from the Zurich generational study using the Zurich neuromotor assessment battery (ZNA) over a 12-year period from the age of 6 to 18 years. The stability was assessed by correlograms of standard deviation scores calculated from age- and gender-adjusted normative values and compared with standing height and full scale intelligence quotient (IQ). While motor tasks of hand, finger and foot (HFT) and contralateral associated movements (CAM) exhibited a moderate stability (summary measure as correlation coefficients between two measurements made 4 years apart: .61 and .60), other tasks (dynamic balance, static balance and pegboard) were only weakly stable (.46, .47 and .49). IQ and height were more stable than neuromotor components (.72 and .86). We conclude that the moderately stable HFT and CAM may reflect “motor traits”, while the stability of the pegboard and balance tasks is weaker because these skills are more experience related and state-dependent. 相似文献
998.
During anti-phased locomotor tasks such as cycling or walking, hemiparetic phasing of muscle activity is characterized by inappropriate early onset of activity for some paretic muscles and prolonged activity in others. Pedaling with the paretic limb alone reduces inappropriate prolonged activity, suggesting a combined influence of contralesional voluntary commands and movement-related sensory feedback. Five different non-target leg movement state conditions were performed by 15 subjects post-stroke and 15 nonimpaired controls while they pedaled with the target leg and EMG was recorded bilaterally. Voluntary engagement of the non-lesioned motor system increased prolonged paretic vastus medialis (VM) activity and increased phase-advanced rectus femoris (RF) activity. We suggest bilateral descending commands are primarily responsible for the inappropriate activity in the paretic VM during anti-phase pedaling, and contribute to the dysfunctional motor output in the paretic RF. Findings from controls suggest that even an undamaged motor system can contribute to this phenomenon. 相似文献
999.
Prior studies of postural coordination have shown inconsistencies between hip-ankle coordination in redundant and non-redundant coordination tasks as well as predictions of the HKB model. These inconsistencies were investigated by testing the hypothesis that there are different hierarchical control structures for redundant (multiple potential task solutions) and non-redundant (a single task solution) coordination tasks (Bernstein, 1996). The transfer between a non-redundant postural tracking task and a redundant scanning task consisting of 16 hip-ankle relative phase patterns from 0° to 337.5° was investigated. The results showed that the transfer between the tasks was transitory, negative and occurred only from the non-redundant to the redundant task. This finding supports the hypothesis that inconsistencies between redundant and non-redundant coordination dynamics may be due to a hierarchical relation between control structures for the performance of these types of tasks. 相似文献
1000.
The primary purpose of the present study was to examine kinematic characteristics and force control during a golf-putting task under a pressure condition. The secondary purpose was to provide an exploratory investigation of the relationship between changes in behavior (kinematics and force control) and performance on the one hand, and psychological (attention and affect) and physiological (arousal level) changes on the other hand. Twenty male novices performed 150 acquisition trials, followed by 10 test trials during a pressure condition induced by performance-contingent distracters: a cash reward or punishment. A three-dimensional motion analysis revealed that, during the pressure test, angular displacements of rotational movements at the horizontal plane and movement time of the arms and club during the backswing and downswing phases all decreased, while acceleration of the elbows during the downswing phase increased. Mean performance indices in all participants’ were unchanged in spite of the kinematic changes under the pressure condition. Multiple regression analyses indicated that the decrement in performance, as well as increased variability of movement time and speed, were more likely to increase when participants shifted their attention to movements. Furthermore, changes in heart rate and negative affect were related to both the increase in movement acceleration and a decrease in grip force. These findings suggest that performance and behavioral changes during golf-putting under pressure can be associated with attentional changes, along with the influences of physiological-emotional responses. 相似文献