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21.
Reactions to published accounts of research with human subjects, as well as research with nonhuman subjects, were assessed by examining citations in several samples of empirical articles in the Journal of the Experimental Analysis of Behavior. A stable, asymmetrical pattern emerged: Nonhuman research was cited in both human and nonhuman articles, but human research was cited primarily in human articles. Thus, human operant research appears to have had little influence on the nonhuman research which constitutes the bulk of the experimental analysis of behavior. Interpretation of this lack of impact depends on the functions one envisions for human research, several of which are discussed.  相似文献   
22.
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   
23.
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   
24.
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   
25.
一、历史运动心理学的基础在于运动学习和动作操作。1920年之前,就有少数人单独地进行一些零星分散的调查。这些调查推动了各种心理变量影响动作操作的研究。首先在美国发表的是观众对自行车比赛的影响。在1918年,伊利诺斯大学的心理学家C·R·格里菲斯对足球运动员和篮球运动员的反应时进行了比较,这仅仅为以后的研究播下了一些种子。在此期间,其它国家(苏联、德国和日本)也有类似的研究。 1920—1940年间,有些人对运动心理学的研究发生了特殊的兴趣。美国的运动心理学之父 C·R·  相似文献   
26.
Three experiments describe the effects of manipulating the frequency of response-reinforcer contiguity in a recycling conjunctive schedule. The schedule arranged that a reinforcer was delivered after 30 s provided at least one response had occurred; otherwise the next cycle started immediately. In Experiment 1, this schedule produced the typical pause–respond–pause pattern, with most responses at mid-interval; and, when a limited number of contiguities between responses and food delivery were added, the pattern became more like the monotonic scallop seen on fixed-interval schedules. In Experiment 2, the schedule was initially presented with an additional contingency that allowed contiguity on every trial. Fixed-interval-like behavior occurred and tended to persist as contiguities were gradually eliminated. In Experiment 3, the recycling conjunctive schedule alternated with a condition in which a large number of contiguities occurred. The pause–respond–pause pattern and fixed-interval-like performance occurred with few or many contiguities, respectively. The results of all three experiments illustrate how contiguity interacts with a small number of other variables to determine performance on interval schedules and illuminate previous findings with fixed-interval and fixed-time schedules.  相似文献   
27.
28.
ABSTRACT 'Ulysses contracts' are an instrument through which a psychiatric patient may prearrange involuntary commitments to be put into effect if the patient satisfies certain diagnostic criteria in the future. Proposals for Ulysses contracts typically impose numerous safeguards. This paper argues against the intuitively plausible safeguard which permits only presently remitted patients to contract. Instead of requiring a patient's remission, it is argued that the appropriate safeguard is the patient's ability, whether remitted or not, to offer good reasons for wishing to contract. In short, what matters is not an executive's character, but an executive's reasons, and a bad executive may have good reasons. Attempts to deny the accessibility of good reasons in unremitted patients are rejected on the ground that psychiatric diagnosis requires psychiatrists to be able to distinguish between good and bad reasons in both remitted and unremitted patients. If psychiatrists cannot do that, psychiatric diagnosis is impossible.  相似文献   
29.
The timing of natural prehension movements   总被引:39,自引:0,他引:39  
Prehension movements were studied by film in 7 adult subjects. Transportation of the hand to the target-object location had features very similar to any aiming arm movement, that is, it involved a fast-velocity initial phase and a low-velocity final phase. The peak velocity of the movement was highly correlated with its amplitude, although total movement duration tended to remain invariant when target distance was changed. The low-velocity phase consistently began after about 75% of movement time had elapsed. This ration was maintained for different movement amplitudes. Formation of the finger grip occurred during hand transportation. Fingers were first stretched and then began to close in anticipation to contact with the object. The onset of the closure phase was highly correlated to the beginning of the low velocity phase of transportation. This pattern for both transportation and finger grip formation was maintained in conditions whether visual feedback from the moving limb was present or not. Implications of these findings for the central programming of multisegmental movements are discussed.  相似文献   
30.
This study examined the relationship between job stress and employees' performance and withdrawal behavior among nurses (N = 440) in two hospitals in a metropolitan Canadian city on the east coast. Job stressors assessed included role ambiguity, role overload, role conflict, and resource inadequacy. Employees' performance was operationalized in terms of job performance, motivation, and patient care skill. Withdrawal behaviors assessed were absenteeism, tardiness, and anticipated turnover. Multiple regressions, curvilinear correlation coefficients, and canonical correlations were computed to test the nature of the relationship between stressors and the criterion variables of the study. In general, data were more supportive of the negative linear relationship between stress and performance than for positive linear or curvilinear relationship. However, the stressor role ambiguity did exhibit a monotonic nonlinear relationship with a number of criterion variables. Employees' professional and organizational commitment were proposed to moderate the stress-performance relationship. However, the data only partially supported the role of the moderators.  相似文献   
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