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871.
Snake fearful college students underwent Standardized Systematic Desensitization (SSD) treatment in which they received instructions designed to induce cognitions of either self- or drug-produced relaxation. Half of the subjects in each of these conditions were also given high expectancy therapy instructions and low expectancy therapy instructions respectively. All four SSD groups showed significantly greater improvement than a no-treatment control group on both the behavior avoidance test (BAT) and the self-report measure of fear. No differences between self- and drug-attributions of relaxation were found on any measure. Subjects' high expectancy ratings were significantly correlated with improvement on self-report measures but not related to BAT performance. 相似文献
872.
873.
Thomas R. Herzog 《Attention, perception & psychophysics》1971,10(4):273-277
Single letters were presented for varying numbers of repeated brief exposures. The S reported on the target after each presentation, identifying only those symbols perceived with certainty. A d’ analysis of the results revealed that target-uncertainty reduction produced significant facilitation in the average level of perceptual sensitivity only in a condition in which the target symbol was exposed prior to each trial. Prior knowledge of the target symbol without prior exposure produced a measurable, but nonsignificant, facilitation in sensitivity. The data suggested that the growth curve normally associated with the repeated-presentations paradigm may be the result of a progressive liberalization of the S’s criterion for reporting in some studies. The data further showed that prior exposure and perhaps prior knowledge can significantly alter the shape of the repetition curve when the target is a single letter. These findings were interpreted as an indication that both amount and kind of target-uncertainty reduction can produce significant changes in the repetition effect for single letters. 相似文献
874.
A. John Ernst Larry Engberg David R. Thomas 《Journal of the experimental analysis of behavior》1971,16(2):177-180
Twelve pigeons were given successive discrimination training involving variable-interval reinforcement for key pecking in the presence of one intensity of monochromatic light randomly alternated with extinction for pecking during another intensity. All of the pigeons were then tested in extinction for generalization along the intensity dimension, and all showed a displacement of maximal responding from the positive stimulus in the direction opposite the negative stimulus. For six of the pigeons, for which the test included only three values beyond the positive stimulus, four showed peaked gradients but two did not, showing monotonic gradients with maximal responding to the most extreme test value. For another six pigeons tested over a wider range, all showed peaked gradients. Thus, when a sufficiently wide range of test values is employed, generalization gradients for visual intensity have the same peaked form as do gradients for qualitative visual dimensions such as wavelength or line angle. 相似文献
875.
876.
877.
Warning responses are described on the basis of interviews with 278 randomly selected families who were evacuated from their homes prior to a flood in Denver, Colorado, on June 16, 1965. Response patterns are analyzed in detail for families who were geographically separated at the time initial warnings were received. Numerous implications for community disaster planning are explicated. 相似文献
878.
Milton D. Hakel Thomas D. Hollmann Marvin D. Dunnette 《Journal of counseling and development : JCD》1968,46(8):762-764
Forty-two years ago, Counts (1925) surveyed the social status of occupations and found a well-defined prestige order, with banker at the top and ditch digger at the bottom. Because of changes wrought by the depression and World War II, Deeg and Paterson (1947) repeated Counts' study and found only minor relative changes in social status. Because of the extensive social and cultural changes since World War II, Counts' study was repeated again, and again only minor relative changes in the social status of occupations were found. The prestige order of the occupations surveyed is remarkably stable. 相似文献
879.
John R. Thomas 《Journal of the experimental analysis of behavior》1968,11(5):609-616
Pigeons' responding was maintained by two concurrently available variable-interval reinforcement schedules. A fixed-ratio punishment schedule of timeout periods from the concurrent reinforcement schedules was arranged for responding during one of the variable-interval schedules. The greater the probability of a timeout after a response on the punished variable-interval schedule (the smaller the fixed ratio that produced timeout), the greater the decline in the relative punished response rates. Relative reinforcement rates remained invariant when relative response rates declined. Both behavioral contrast and induction effects were observed on the unpunished variable-interval schedule as a function of timeout punishment of the other schedule. 相似文献
880.
The five pigeons in Group 1 were given successive intradimensional discrimination training in which responses to a line of 49 degrees were reinforced on a variable-interval schedule and responses to a line of 33 degrees were not reinforced. Subsequent generalization testing with other line orientations revealed a peak shift from the positive stimulus in the direction away from the negative stimulus in all subjects. The four pigeons in Group 2 received successive discrimination training with the 49 degrees value on the key during both stimuli. During the negative stimulus, however, the floor was tilted 16 degrees counterclockwise. When tested (with the floor flat) these subjects showed peak shifts similar to those observed with Group 1. A third group of three pigeons, given successive interdimensional discrimination training with the 49 degrees line as the positive stimulus and the absence of the line as the negative, showed no peak shift in a subsequent generalization test. It was concluded that tilting the floor on which the pigeon stood systematically distorted the bird's visual perception of the orientation of the line in a manner consistent with the results of other studies in this laboratory. 相似文献