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121.
在阿尔都塞的马克思著作研究中,多元决定和结构因果性这两个概念是十分重要的。本文将通过考察阿尔都塞对这两个概念在理解马克思的“方法论”上的价值和应用的论述,来解释这两个概念。但这种研究方法并不认为在《资本论》或其他著作中,马克思实际上有一种具体的或明确的方法论。对我们来说,马克思主义中是否有方法论仍然是一个未解决的问题。对于任何的马克思方法论的探讨,这些概念都是重要的。本文的任务之一就是表明,马克思在政治经济学中的贡献和“理论革命”不能简单地用方法论来描绘。马克思对黑格尔的辩证法思  相似文献   
122.
The reliability of the Thematic Apperception Test   总被引:1,自引:0,他引:1  
Controversy over the TAT's reliability may stem largely from the mis-application of traditional psychometric measures, which are inappropriate to this test. The TAT is implicitly based on a multiple regression model, for which coefficient alpha is not appropriate. Also, test-retest correlations may be adversely affected by the standard instructions to write a "creative" story. In a test-retest study, 47 high school students retook the TAT after a year with instructions designed to break the implicit set to produce a new and different story from that previously written. The test-retest correlations were r = .48 (need for affiliation) and .56 (need for intimacy), or approximately the same as those for, e.g., the MMPI, 16PF, and CPI, It was demonstrated that this high stability over time was not due to subjects' recalling and repeating previous responses. Finally, it was shown that alpha considerably underestimated the test-retest reliability, contrary to assumptions of classical psychometrics.  相似文献   
123.
The growth of stability: postural control from a development perspective   总被引:5,自引:0,他引:5  
This study compared central nervous system organizational processes underlying balance in children of three age groups: 15-31 months, 4-6 years, and 7-10 years, using a movable platform capable of antero-posterior (A-P) displacements or dorsi-plantar flexing rotations of the ankle joint. A servo system capable of linking platform rotations to A-P sway angle allowed disruption of ankle joint inputs, to test the effects of incongruent sensory inputs on response patterns. Surface electromyography was used to quantify latency and response patterns. Surface electromyography was used to quantify latency and amplitude of the gastrocnemius, hamstrings, tibialis anterior, and quadriceps muscle responses. Cinematography provided biomechanical analysis of the sway motion. Results demonstrated that while directionally specific response synergies are present in children under the age of six, structured organization of the synergies is not yet fully developed since variability in timing and amplitude relationships between proximal and distal muscles is high. Transition from immature to mature response patterns was not linear but stage-like with greatest variability in the 4- to 6- year-old children. Results from balance tests under altered sensory conditions (eyes closed and/or ankle joint inputs altered) suggested that: (a) with development a shift in controlling inputs to posture from visual dependence to more adult-like dependence on a combination of ankle joint and visual inputs occurred in the 4- to 6-year-old, and reached adult form in the 7- to 10-year-old age group. It is proposed that the age 4-6 is a transition period in the development of posture control. At this time the nervous system (a) uses visual-vestibular inputs to fine tune ankle-joint proprioception in preparation for its increased importance in posture control and (b) fine tunes the structural organization of the postural synergies themselves.  相似文献   
124.
The role played by reflex pathways in the production of movement has been a significant issue for motor control theorists interested in a wide variety of motor behaviors. From studies of locomotion and chewing, it appears that gains in reflex pathways can be altered so that activity in these pathways does not produce destabilizing responses during movement. In speech production, recent experimental evidence has been interpreted to suggest that autogenetic lip reflexes (perioral reflexes) are suppressed during sustained phonation or speech production. The present study was conducted to assess the effects of phonation, direction of movement, and ongoing speech production on reflex responses of lip muscles. The present results suggest, in contrast to earlier work, that this reflex pathway is not suppressed or absent because the amplitude of the observed response depends upon the activation levels of the various muscles of the lower lip and, therefore, indirectly on the nature of the gesture the subject is instructed to produce.  相似文献   
125.
In Experiment 1 six monkeys were tested with discriminative relations that were backward relative to their training in a 0-second conditional (“symbolic”) matching procedure. Although there was some indication of backward associations, the evidence was generally weak, and statistical evaluations did not reach conventional significance levels. Unlike children, who show backward associations to the point of symmetry, monkeys and pigeons display at best only weak and transient backward associations. In Experiment 2 associative transitivity was assessed across two sets of conditional matching tasks. All four monkeys tested demonstrated strong transitivity. In contrast, in Experiment 3 there was no evidence of transitivity in three pigeons tested under conditions closely comparable to those of Experiment 2. These results may identify some key features of interspecies differences and contribute to analyses of serial learning in animals.  相似文献   
126.
Modulation of the responses to perturbation applied during different phases of three rhythmic movements in humans-running, cycling, and hopping-was studied. The perturbation was an electrical stimulus. The results showed gating and modulation of the responses in both ipsi- and contralateral limb muscles. The responses during running and cycling were only excitatory in nature, while during hopping an inhibitory response was observed. These responses were not correlated with the normal activity during the movement. The latency of the response in general was not altered for different stimulation phases. The alterations in the step cycle demonstrated overt behavioral changes due to the responses. There were differences between the responses observed during these movements and walking. In running, the major adaptation to perturbations appears to be in the contralateral side as seen in the changes in the step cycle. During cycling (except for one phase) and hopping, the same set of muscles was activated in response to perturbation. This represents a simplifying strategy in response organization. The dependency of the response on the task characteristics, postural stability requirement, and external constraints imposed on the subject is discussed. These studies provide insights into task-dependent strategies adopted by the nervous system to meet unexpected perturbation during rhythmic movements in humans.  相似文献   
127.
A behavior-analytic critique of self-efficacy theory is presented. Self-efficacy theory asserts that efficacy expectations determine approach behavior and physiological arousal of phobics as well as numerous other clinically important behaviors. Evidence which is purported to support this assertion is reviewed. The evidence consists of correlations between self-efficacy ratings and other behaviors. Such response-response relationships do not unequivocally establish that one response causes another. A behavior-analytic alternative to self-efficacy theory explains these relationships in terms of environmental events. Correlations between self-efficacy rating behavior and other behavior may be due to the contingencies of reinforcement that establish a correspondence between such verbal predictions and the behavior to which they refer. Such a behavior-analytic account does not deny any of the empirical relationships presented in support of self-efficacy theory, but it points to environmental variables that could account for those relationships and that could be manipulated in the interest of developing more effective treatment procedures.  相似文献   
128.
Persistence and its assessment have been studied since the 1920s. One common approach in measuring persistence has been through testing the subject's ability to solve difficult or monotonous problems. Another approach has been through questionnaires. Although persistence is very important in academic achievement and in the general development of personality, no questionnaires have been developed for measuring persistence in children. The present research concerns the development of such a scale. It includes 40 items and was tested on 322 Israeli children aged 7-13. The internal reliability of the scale (Cronbach alpha) was .66, and the test-retest reliability after 6 months was .77. The scale differentiated active gymnasts from non-gymnasts as well as persistent gymnasts from dropout gymnasts. In addition, significant correlations were found between the scale and the need-persistence measure of the Rosenzweig Picture Frustration Study, Locus of Control, and other measures. We discuss these findings along with the significance of persistence in everyday life.  相似文献   
129.
Variable-interval schedules of timeout from avoidance   总被引:2,自引:2,他引:0       下载免费PDF全文
Rats were trained on concurrent schedules in which pressing one lever postponed shock and pressing the other occasionally produced a 2-min timeout during which the shock-postponement schedule was suspended and its correlated stimuli were removed. Throughout, the shock-postponement schedule maintained proficient levels of avoidance. Nevertheless, in Experiment 1 responding on the timeout lever was established rapidly, was maintained at stable levels on variable-interval schedules, was extinguished by withholding timeout, was reestablished when timeout was reintroduced, and was brought under discriminative control with a multiple variable-interval extinction schedule of timeout. These results are in contrast with Verhave's (1962) conclusion that timeout is an ineffective reinforcer when presented to rats on intermittent schedules. In Experiment 2 the consequence of responding on the timeout lever was altered so that the shock-postponement schedule remained in effect even though the stimulus conditions associated with timeout were produced for 2 min. Responding extinguished, indicating that suspension of the shock-postponement schedule, not stimulus change, was the source of reinforcement. By establishing the reinforcing efficacy of timeout with standard variable-interval schedules, these experiments illustrate a procedure for studying negative reinforcement in the same way as positive reinforcement.  相似文献   
130.
目的、意向和意识   总被引:1,自引:0,他引:1  
本文提出了一个意向性目标搜寻的计算机模型,它有两个部分,静态部分包括一个目标表征和到达这个目标的程序。动态部分是一个感觉输入、中间信息加工,行为输出的重复的反馈循环。人类意向必然伴有意识,但机器人则可能无意识而有意向。 利用目标搜寻系统机器人模型,我们对目标搜寻系统的目的连续统下了定义;这个连续统从简单的直接反应系统一直到意向性系统。对这个目的连续统有两种传统的解释:一是柏拉图、亚里士多德和普罗提诺的终极原因理论,二是希腊原子论者和现代进化生物学家的还原主义学说。本文评价了这些学说。 本文考察了几种类型的意识机能,提出了以自动机为依据的意识理论,比较了人类和计算机。从计算机结构的角度来看,人类意识是一类特殊的计算机控制系统。  相似文献   
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