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991.
Turning biases in humans and animals are known to be related to dopaminergic asymmetry between the brain hemispheres. A laboratory method, in which turning preference was evaluated, was adapted based upon the turning of the subject toward a particular sound in a square room. One of the aims of this study was to investigate the reliability of this method with children, and the other aim was to research the turning preference in boys and girls. 31 children between 7 and 13 yr. old volunteered as subjects, and 17 subjects were retested. The subjects tended significantly to turn leftward (60.1%), and fewer girls (53.7%) turned to the left than boys (66.2%). The correlation between the test and the retest was significant (r=.79, p< .01). Most studies have indicated that humans in childhood and adulthood exhibit left-turning preference, but conflicts between the results obtained on different types of rotation tasks have suggested that hemispheric dopaminergic activity might affect preference. That needs study.  相似文献   
992.
10 male collegiate runners (M age = 21.4, SD = 1.5 yr.) ran on a treadmill with no body-weight support (BWS), 20% BWS, and 40% BWS conditions. In addition, they wore three different commercially available harnesses at the 20% and 40% BWS conditions. The aim was to run on the treadmill at a fast speed while maintaining an adequate step length. The purpose was to investigate how each harness changed running gait, and the differences in running gait between the harnesses with various body-weight support. Analysis of variance indicated significant restriction of upper body torso rotation between the harnesses at the 40% BWS conditions. Body-weight support resulted in a longer stride, decreased cadence, less vertical displacement of the center of mass, and diminished hip and ankle joint excursions. These changes indicated that increased body-weight support results in longer steps with the foot contacting the belt for a shorter period of time with less leg angular changes throughout the running cycling.  相似文献   
993.
Recent reports have shown that saccades can deviate either toward or away from distractors. However, the specific conditions responsible for the change in initial saccade direction are not known. One possibility, examined here, is that the direction of curvature (toward or away from distractors) reflects preparatory tuning of the oculomotor system when the location of the target and distractor are known in advance. This was investigated by examining saccade trajectories under predictable and unpredictable target conditions. In Experiment 1, the targets and the distractors appeared unpredictably, whereas in Experiment 2 an arrow cue presented at fixation indicated the location of the forthcoming target prior to stimulus onset. Saccades were made to targets on the horizontal, vertical, and principal oblique axis, and distractors appeared simultaneously at an adjacent location (a separation of +/- 45 degrees of visual angle). On average, saccade trajectories curved toward distractors when target locations were unpredictable and curved away from distractors when target locations were known in advance. There was no overall difference in mean saccade latencies between the two experiments. The magnitude of the distractor modulation of saccade trajectory (either toward or away from) was comparable across the different saccade directions (horizontal, vertical, and oblique). These results are interpreted in terms of the time course of competitive interactions operating in the neural structures involved in the suppression of distractors and the selection of a saccade target. A relatively slow mechanism that inhibits movements to distractors produces curvature away from the distractor. This mechanism has more time to operate when target location is predictable, increasing the likelihood that the saccade trajectory will deviate away from the distractor.  相似文献   
994.
The study was designed to examine the sport achievement orientations of male wheelchair basketball athletes who differed by onset of experienced disability (congenital and acquired). The full Sport Orientation Questionnaire was administered to 166 U.S. national athletes. Athletes with congenital disabilities had higher mean scores than their peers with acquired disabilities on the three subscales of the full form and on the extraction items as a short form (Competitiveness, Win Orientation, and Goal Orientation). Multivariate analysis of variance yielded no significant differences between groups. Significant differences on Competitiveness and Goal Orientation, with a higher mean were found for the group with congenital disabilities than for the group with acquired disabilities. The results are discussed in relation to the literature, nature of wheelchair basketball, and application of the test to such athletes.  相似文献   
995.
The aim of this study was to adapt the Multisource Assessment of Social Competence Scale to the Greek language. The validity and reliability of the scale were examined in three studies with 209, 192, and 147 sixth-grade students, respectively. The subscale structure of the Multisource Assessment of Social Competence Scale was supported through exploratory and confirmatory factor analysis. The hypothesized two main dimensions, Prosocial and Antisocial behavior, were divided into two factors, Cooperating skills and Empathy for Prosocial behavior and Quick-temperedness and Disruptiveness for Antisocial behavior. Internal consistency and test-retest reliability were high. Additionally, correlations between each factor and social desirability scores were nonsignificant. The resultant model of the present study is a behavior rating scale that should be considered a reliable choice for assessing Greek middle school students' social skills.  相似文献   
996.
This study explores the effects of stress, trauma, coping and growth orientation on subjective well-being. Based on cognitive stress theory, it was hypothesized that adversity may contribute to increased or decreased well-being, depending on the subsequent meaning these experiences are given. Survey data from Norwegian UN/NATO veterans (N= 142) showed that stress and well-being were negatively associated (r=-0.20, p < 0.05) at the level of zero-order correlations. However, a full structural equation model revealed that the effect of stress on well-being was mediated positively through a problem-focused coping process combined with a growth component. Stress was negatively mediated through an avoidant-focused coping process and a distress component. The effect from stress was fully mediated in the model. The hypothesis that stress can produce both increased and decreased subjective well-being was confirmed.  相似文献   
997.
We have previously proposed that cortical auditory-vocal networks of the monkey brain can be partly homologized with language networks that participate in the phonological loop. In this paper, we suggest that other linguistic phenomena like semantic and syntactic processing also rely on the activation of transient memory networks, which can be compared to active memory networks in the primate. Consequently, short-term cortical memory ensembles that participate in language processing can be phylogenetically tracked to more simple networks present in the primate brain, which became increasingly complex in hominid evolution. This perspective is discussed in the context of two current interpretations of language origins, the "mirror-system hypothesis" and generativist grammar.  相似文献   
998.
The present study compared the automaticity levels of persons who stutter (PWS) and persons who do not stutter (PNS) on a practiced finger sequencing task under dual task conditions. Automaticity was defined as the amount of attention required for task performance. Twelve PWS and 12 control subjects practiced finger tapping sequences under single and then dual task conditions. Control subjects performed the sequencing task significantly faster and less variably under single versus dual task conditions while PWS' performance was consistently slow and variable (comparable to the dual task performance of control subjects) under both conditions. Control subjects were significantly more accurate on a colour recognition distracter task than PWS under dual task conditions. These results suggested that control subjects transitioned to quick, accurate and increasingly automatic performance on the sequencing task after practice, while PWS did not. Because most stuttering treatment programs for adults include practice and automatization of new motor speech skills, findings of this finger sequencing study and future studies of speech sequence learning may have important implications for how to maximize stuttering treatment effectiveness. Educational objectives: As a result of this activity, the participant will be able to: (1) Define automaticity and explain the importance of dual task paradigms to investigate automaticity; (2) Relate the proposed relationship between motor learning and automaticity as stated by the authors; (3) Summarize the reviewed literature concerning the performance of PWS on dual tasks; and (4) Explain why the ability to transition to automaticity during motor learning may have important clinical implications for stuttering treatment effectiveness.  相似文献   
999.
The generalized optic acceleration cancellation theory of catching   总被引:6,自引:0,他引:6  
The generalized optic acceleration cancellation (GOAC) theory of catching proposes that the path of a fielder running to catch a ball is determined by the attempt to satisfy 2 independent constraints. The 1st is to keep the angle of elevation of gaze to the ball increasing at a decreasing rate. The 2nd is to control the rate of horizontal rotation necessary to maintain fixation on the ball. Depending on the lateral velocity of the ball relative to the fielder, this rate may be zero or constant at a negative or positive value. The authors show that a simulated fielder implementing the GOAC strategy follows a path indistinguishable from that of real fielders running to catch balls thrown on the same trajectories.  相似文献   
1000.
This research focused on the syllable as a processing unit in handwriting. Participants wrote, in uppercase letters, words that had been visually presented. The interletter intervals provide information on the timing of motor production. In Experiment 1, French participants wrote words that shared the initial letters but had different syllable boundaries. In Experiment 2, French- and Spanish-speaking participants wrote cognates and pseudowords with a letter sequence that was always intrasyllabic in French and intersyllabic in Spanish. In Experiment 3, French-Spanish bilinguals wrote the cognates and pseudowords with the same type of sequences. In the 3 experiments, the critical interletter intervals were longer between syllables than within syllables, indicating that word syllable structure constrains motor production both in French and Spanish.  相似文献   
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