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191.
Second-order conditioning of the rabbit’s nictitating membrane response (NMR) was investigated when second-order trials (CS1-CS2) were intermixed with first-order trials (CS2-US) from the outset of training. Experiment 1 showed that CR acquisition to CS1 was inversely related to the CS1-CS2 interval but nevertheless extended to an interval of 8,400 ms. Experiment 2 revealed that CR acquisition of CS1 was an inverted-U function of the number of CS1-CS2 trials relative to a fixed number of CS2-US trials. Experiment 3 directly contrasted second-order conditioning with a reinforced serial compound procedure (CS1-CS2-US) and a mixed procedure in which second-order trials were intermixed with the reinforced serial compound. Second-order conditioning was about half the strength of either the reinforced serial compound or the mixed procedure, which were similar. The present results are discussed with respect to the relative strength of excitatory and inhibitory processes in second-order conditioning.  相似文献   
192.
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   
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Two studies were conducted in all-electric townhouses and apartments in the winter (N = 83) and summer (N = 54) to ascertain how energy conservation strategies focusing on thermostat change and set-backs and other low-cost/no-cost approaches would affect overall electricity use and electricity used for heating and cooling, the home thermal environment, the perceived comfort of participants, and clothing that was worn. The studies assessed the effectiveness of videotape modeling programs that demonstrated these conservation strategies when used alone or combined with daily feedback on electricity use. In the winter, the results indicated that videotape modeling and/or feedback were effective relative to baseline and to a control group in reducing overall electricity use by about 15% and electricity used for heating by about 25%. Hygrothermographs, which accurately and continuously recorded temperature and humidity in the homes, indicated that participants were able to live with no reported loss in comfort and no change in attire at a mean temperature of about 62 degrees F when home and about 59 degrees F when asleep. The results were highly discrepant with prior laboratory studies indicating comfort at 75 degrees F with the insulation value of the clothing worn by participants in this study. In the summer, a combination of strategies designed to keep a home cool with minimal or no air conditioning, in conjunction with videotape modeling and/or daily feedback, resulted in overall electricity reductions of about 15% with reductions on electricity for cooling of about 34%, but with feedback, and feedback and modeling more effective than modeling alone. Despite these electricity savings, hygrothermograph recordings indicated minimal temperature change in the homes, with no change in perceived comfort or clothing worn. The results are discussed in terms of discrepancies with laboratory studies, optimal combinations of video-media and personal contact to promote behavior change, and energy policies that may be mislabeled as sacrificial and underestimate the effectiveness of conservation strategies such as those investigated in these studies.  相似文献   
196.
The possibility of isolating personality types using 16 PF profiles was studied by utilizing a Q-type factor analytic procedure. Four modal profiles, characteristic of major clusters of subjects, were derived and cross validated. These four major types successfully classified approximately 2/3 of the 16 PF protocols (n = 1037), and classified similar proportions of previously published profiles. Variation of classification rates as a function of race and sex was described, and strategies for utilizing the profiles for research and interpretive purposes were outlined.  相似文献   
197.
Two experiments were carried out to investigate whether visual imagery was used in representing transitive linear ordering relationships. Subjects were presented with passages describing either a linear ordering or a set inclusion relationship, while being subjected to either visual or verbal interference. Performance was tested by asking subjects to judge the truth or falsity of statements concerning both the information presented in the passages and inferences that could be drawn from this information. In neither experiment was there any evidence for the linear ordering material being selectively disrupted by the visual interference task, as would have been predicted by the imagery theory. Thus it is concluded that linear orderings are probably not represented as visual images.  相似文献   
198.
Nineteen agoraphobic outpatients were randomly assigned to four sessions of either (1) Exposure: planning and discussion of exposure homework tasks requiring patients to enter and remain in phobic situations hitherto avoided; or (2) Control: discussion of marital, family and social difficulties and strategies for dealing with these.A small but significant effect was found at post-test and at one month follow-up in favour of the exposure condition. It is suggested that this variable should be controlled in future relevant experiments and is worth including as an inexpensive expedient of active treatment of phobias.  相似文献   
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