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891.
OPTIMAL MOVEMENT SELECTION   总被引:3,自引:0,他引:3  
  相似文献   
892.
893.
In spite of numerous demonstrations that America's youth can be effectively educated with behavior analytic teaching techniques, few of the country's children are benefiting from the technology. In addition scholarly reviews of effective teaching strategies have often omitted reference to behavior analysis. One way to look at this problem is as a two-step operation. First, it is necessary to determine procedures that work; second it is necessary to devise strategies for effective dissemination. The present issue of JOBE (Vol. 1, No. 3, Sept. 1991) contains the recommendations of six outstanding behavioral educators as to how to deal with the dissemination problem. The initial article by Pumroy and McIntire describes the activities of an organization which trains school psychologists and teachers to use behavioral procedures and advocates for the techniques with a number of audiences. Next, Engelmann suggests that the public have more control over school activities and that legal action be taken against irresponsible administrative decisions. Hall advocates for less labor-intensive procedures and the sale of curricular materials based on behavioral principles. Binder proposes that dissemination of the technology become a private endeavor that responds to consumer needs. Rosenfield describes a collaborative model of consultation that increases treatment adherence. Finally, Albers and Greer describe research that isolates a key teacher behavior that results in greater academic proficiency.  相似文献   
894.
Adult subjects were presented with two auditory stimuli per trial, and their task was to decide which of the two was longer in duration. An adaptive psychophysical procedure was used. In Experiments 1, 2, and 4, the base duration was 50 msec, whereas in Experiment 3, the base duration was 1 sec. In Experiments 1, 2, and 4, it was found that filled intervals (continuous tones) were discriminated more accurately than empty intervals (with onset and offset marked by clicks). It was concluded that this difference was perceptual rather than cognitive in nature, since performance on filled and empty intervals was not affected by increasing cognitive load in a dual-task procedure (Experiment 2) but was affected by backward masking (Experiment 4). In contrast, the results of Experiment 3 showed that duration discrimination of filled auditory intervals of longer duration was cognitively influenced, since performance was impaired by increasing cognitive load. Implications for notions of perceptual processing and timing mechanisms tanderlying differences in duration discrimination with filled and empty intervals are discussed.  相似文献   
895.
In these experiments, two plates were grasped between the thumb and forefinger and squeezed together along a linear track. An electromechanical system presented a constant resistance force during the squeeze up to a predetermined location on the track, whereupon the force effectively went to infinity (simulating a wall) or to zero (simulating a cliff). The task of the subject was to discriminate between two alternative levels of the constant resistance force (a reference level and a reference-plus-increment level). Results of these experiments indicate a just noticeable difference of roughly 7% of the reference force using a one-interval paradigm with trial-by-trial feedback over the ranges 2.5≤F o≤10.0 newtons, 5≤D≤30 mm, 45≤S≤125 mm, and 25≤V≤160 mm/sec, whereF o is the reference force,D is the distance squeezed,S is the initial finger-span, andV is the mean velocity of the squeeze. These results, based on tests with 5 subjects, are consistent with a wide range of previous results, some of which are associated with other body surfaces and muscle systems and many of which were obtained with different psychophysical methods.  相似文献   
896.
In a series of experiments, the ability of a single lithium preexposure to disrupt CS effectiveness was assessed using a latent inhibition procedure. Lithium preexposure administered proximal (90 min) to a saccharin familiarization trial reduced latent inhibition whereas a similar administration more distal (360 min) to flavor familiarization failed to do so. Additional experiments demonstrated that this socalled “US overshadowing” effect was not attributable to sensitization (Experiment 2), excitatory backward conditioning (Experiment 3), or state dependency (Experiment 4). The implications of US overshadowing for proximal US-preexposure effects are discussed.  相似文献   
897.
898.
Efron'sMonte Carlo bootstrap algorithm is shown to cause degeneracies in Pearson'sr for sufficiently small samples. Two ways of preventing this problem when programming the bootstrap ofr are considered.  相似文献   
899.
A brief review is provided of the capacity of neural tissue transplants to reinnervate the deafferented hippocampus and repair functional deficits induced by the lesion. The techniques for transplantation of solid pieces of embryonic septum, locus coeruleus or raphe nuclei, or tissue suspensions of embryonic septum, to the adult rat hippocampus are described. Such grafts manifest good long-term survival, provide a good reinnervation of the hippocampus that is histochemically and biochemically appropriate and specific, can establish ultrastructural synaptic contacts with the host, and are electrophysiologically active. Rats with septal grafts manifest recovery of the capacity to learn certain aspects of radial 8-arm maze, T-maze alternation and Morris water-maze tasks. Rats with locus coeruleus grafts manifest an amelioration of lesion-induced hyperactivity. It is concluded that neural tissue transplantation provides a powerful new tool in the study of the functional organization of the hippocampus and its various neurotransmitter-specific afferent systems.  相似文献   
900.
Premenstrual syndrome is a condition with cyclical mood changes occurring in 30 % of the female population of fertile ages. The symptom development is very closely related to the luteal phase indicating the existence of one or more factors during the luteal phase that provoke mental symptoms in sensitive patients. This is further supported by the fact that hysterectomized women with no menstrual bleedings but with the ovarian hormone cycle continue to show cyclical mood changes without having the cycle phase. The nature of the symptom provocating factor is still unknown but the ovarian hormones progesterone and/or estradiol are suspected. This as certain women taking oral contraceptives and sequential postmenopausal estrogen-progestagen treatment achieve mood changes. Psychological and personality factors are probably also involved, at least in the degree of the mood change and the type of mood experienced.  相似文献   
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