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891.
Hungry rats were allowed to lick an 8% sucrose solution and then one of four lick-shock contingency conditions was superimposed on the licking baseline. These conditions were: free-operant avoidance, free shock, punishment, and no shock. From highest to lowest response rates, the groups fell in the order-avoidance, no shock, free shock, and punishment. Lick rates adjusted rapidly to introduction and removal of the contingencies. Post-shock responding was lowest in the punishment condition and highest in the free shock condition. No method was found simultaneously to equate shock frequency and separate response rates for the three shock contingency conditions. Only small, or no, reductions in shock rate occurred over sessions under the free-operant avoidance schedule when the shock-shock interval was 10 sec but large reductions occurred when the shock-shock interval was reduced to either 1 or 2 sec.  相似文献   
892.
893.
894.
This investigation continues the exploration of a largely neglected topic in the field of attention, levels of mental concentration, by ascertaining under optimal conditions the capacity for shifting quickly from one level to another. Previous research in our laboratory had applied a set of five post-hypnotically cued levels of concentration or “cognitive arousal”, covering a very wide range, to a variety of perceptual and cognitive tasks. In the present study two highly trained undergraduate hypnotic subjects, one male and one female, were given progressively shorter time durations in which to respond to the post-hypnotic cues before viewing tachisto-scopically flashed consonants under cue influence. The results indicate a striking capacity to shift degrees of cognitive arousal very rapidly to one extreme or the other, on the order of 100 ms or less.  相似文献   
895.
An investigation is reported into pausing and grouping during the serial learning of letter strings, when presented randomly by length and when presented in ascending order. Mean pause times for the reading and recall of longer lists were significantly greater than for lists of shorter span due to extended pausing at specific list positions. In general, reading rhythms were duplicated during recall. Subjects were highly consistent in maintaining their level of pause duration across lists and responded to additions in list length by increasing their number of groups, not by increasing group size. Triadic sequences were the most popular form of spontaneous organization. Pausing measures are discussed as indices of organizational strategies.  相似文献   
896.
This article describes a practical model for a systematic, sequential approach to career development in the K-12 curriculum. The model builds on career development principles and vocational development tasks; it is self-concept oriented and uses a variety of methods and media in its implementation. Several strategies for facilitating career development are suggested for each level.  相似文献   
897.
898.
Subjects were presented with simultaneously visual and auditory material. They were instructed to attend to only one modality but were required to recall materials from both modalities, one before the other. Results supported a previous suggestion that visual recall is minimum under conditions of simultaneous presentation. That is, in situations where S is allowed to divide his attention between both inputs, visual recall was no greater than when his attention was directed away from visual input and to auditory input. It was noted that this difference in recall between the two modalities was limited to verbal material, as other data indicate the opposite effect for nonverbal material.  相似文献   
899.
Two methods for training the absolute judgment of pitch, reference training and series training, were studied. Reference training concentrated during training on the identification of three reference tones in a set of nine pure tones, while series training gave equal weight during training to the identification of all nine tones. Results of pre- and posttraining tests, scored for the number of correct judgments, showed that reference training was more effective than series training for listeners with musical experience. In addition, discriminability (d′) scaling of pre- and posttest performance indicated that reference training was particularly effective for training listeners with musical experience when the nine tones of a set were grouped into three pitch classes—high, medium, and low pitch. Listeners without musical experience benefited from both training methods, but their overall improvement was less than that for musical listeners.  相似文献   
900.
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