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61.
Three experiments are described which elaborate some of the conditions under which rats will contact and manipulate a periodically presented retractable lever. Experiment 1 demonstrated that (i) initial manipulative oral and manual contact with the lever was facilitated if the rat had previous experience of food delivery in the experimental chamber; (ii) persistence in contacting the lever on successive presentations was a function of whether food continued to be presented in the experimental environment; and (iii) food satiation significantly reduced the tendency of the rat to contact the lever even though an expectancy of food had previously been established under conditions of food deprivation. Experiment 2 suggested that the tendency to approach and contact the lever was in part a function of the local moment-to-moment conditional probability of food delivery. Experiment 3 found that the probability of contacting the lever was higher during presentation of an auditory CS signaling a high rate of food delivery than during stimuli signaling no food at all. These results are interpreted as suggesting that the food-signaling aspects of an appetitive CS and that CS's ability to generate signal-directed behaviors are experimentall separable properties. 相似文献
62.
63.
Harvey Charles Peters Bagmi Das Mina Attia Maggie M. Parker 《Journal of Employment Counseling》2023,60(1):2-16
Higher education faculty worldwide experienced heightened stressors due to the COVID-19 pandemic, from completing their professional roles and responsibilities virtually to balancing personal and professional stressors. Consequently, the pandemic created many adjustments for pre-tenure counseling faculty across research, teaching, and service. In response to this pandemic, we explored the impact of the COVID-19 pandemic on the personal and professional lives of four pre-tenure counseling faculty members. Accordingly, we used collaborative autoethnography to investigate our experiences and narratives as pre-tenure counseling faculty, which resulted in seven overarching themes. We discussed the implications for practice, advocacy, education, and faculty training. 相似文献
64.
David S. Emmerich James L. Gray Charles S. Watson David C. Tanis 《Attention, perception & psychophysics》1972,11(1):65-72
Response latencies were obtained from 10 Ss in auditory signal-detection experiments. The response latencies were inversely related to certainty that a signal was (or was not) presented. The S’s decision criterion was found to have an influence on response latency, which was consistent with the hypothesis that stimuli close to the current criterion elicit longer response latencies than stimuli more distant from the criterion. Comparisons among receiver operating characteristics derived from binary decisions, from the latencies of binary decisions, and from confidence ratings show that response latencies and binary decisions together yield more information about the stimulus than does the binary decision alone. However, the increment in information gained from the measurement of response latencies is in general (though not for every S) smaller than that gained by shifting from yes-no responses to a confidence-rating procedure. 相似文献
65.
A circuit to permit an electronic drinkometer to operate during footshock is described. The circuit employs a diode matrix that allows all grid bars to be connected at one point to form one electrode of the drinkometer; it is isolated at another point so as not to shortcircuit the impressed footshock. 相似文献
66.
Measures of test parsimony and factor parsimony are defined. Minimizing their weighted sum produces a general rotation criterion
for either oblique or orthogonal rotation. The quartimax, varimax and equamax criteria are special cases of the expression.
Two new criteria are developed. One of these, the parsimax criterion, apparently gives excellent results. It is argued that
one of the most important factors bearing on the choice of a rotation criterion for a particular problem is the amount of
information available on the number of factors that should be rotated.
This research was supported by the National Research Council of Canada research grant 291-13 to Dr. G. A. Ferguson. 相似文献
67.
68.
Pressurized air was repeatedly associated with one of two frequencies of flashing light during performance of a VI 30-sec positive reinforcement schedule by stump-tailed monkeys. As revealed by the relative suppression of bar presses to each of the two visual stimuli, the Ss learned to discriminate between the different flicker frequencies. However, they also showed signs of adapting to the airblast during the course of training, and its location had to be changed in order to maintain discriminative suppression. 相似文献
69.
The detection of luminance increments in a homogeneously lighted field was studied as a function of the area and perimeter of the luminance increment. Sixteen targets representing all possible combinations of four values of area and four values of perimeter were foveally presented. Exposure durations were short (25 to 40 msec). Results of both an analysis of variance and linear discriminant analysis indicated that detection probability increases as area increases, but neither variations in perimeter nor perimeter-area combinations produced effects that were significant oyer the experiment as a whole. The linear discriminant analysis revealed individual differences in the effects of perimeter and area on detection probability. Results were contradictory to Kristofferson’s (1957) “element contribution theory” and gave only slight support to Hecht’s (Lamar, Hecht, Shlaer, & Hendley, 1947) “border-quantum theory.” 相似文献
70.