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961.
Individuals with brain damage often encounter visual perceptual and visuo-motor difficulties. Studies have indicated an improvement in exceptional individuals' performances when the colors of figure-ground materials were reversed. Effects of reversals were studied for spastic cerebral palsied and normal children's scores on the Developmental Test of Visual-motor Integration and the Motor-free Visual Perception Test. Normal children performed better than the cerebral palsied children on all tests; the cerebral palsied children performed best on the reversed-format Motor-free Visual Perception Test. Reversal affected neither group's scores on visual-motor integration.  相似文献   
962.
Evidence relating to the hypothesis on facial feedback which ties the experience of discrete emotions to feedback from innately patterned facial expressions is discussed. Strong evidence is deduced for a more general form of the hypothesis, but the requirements of necessity and sufficiency representing the strictest form are only satisfied within narrow limits of experimental manipulations which are not common to all investigations. Evidence is deemed to support a relationship between facial expression and emotion, but facial expression is regarded as one of many systems and cannot be assigned an exclusive role (either as first system or as necessary system).  相似文献   
963.
A paradoxical instruction was used to treat a 10-yr.-old boy's complaint of crying when unable to sleep and the daytime equivalent of fearing the public display of crying when failing at sports performances. The instruction resolved both the sleep disturbance and the public crying. The results suggest that, like adults, children may experience anxiety about sleep difficulties and that paradoxical intention may have promise for the treatment of some children's insomnia.  相似文献   
964.
The relationship between cognitive style and illusion magnitude was examined using the assimilation and contrast Delboeuf distortions. As in previous research, field dependence correlated positively with assimilation; however, a significant negative correlation with contrast was also found, suggesting that, while field dependence may involve the illusory integration of the stimulus field, field independence may involve its equally illusory differentiation.  相似文献   
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968.
Rats were given backward pairings of a tone (CS) and shock (US) and were then tested for response to the CS in a lick suppression test. Animals given a cuing or reminder treatment prior to the test exhibited enhanced suppression in the presence of the tone relative to a variety of control conditions. The cue-induced suppression enhancement did not appear to result from sensitization or short-term motivational changes nor did it seem to depend on second-order conditioning of the test context. The effect appeared more robust as the number of backward conditioning trials preceding the cue increased. The results were discussed in terms of current explanations of backward conditioning effects.  相似文献   
969.
Handling time and choice in pigeons   总被引:2,自引:1,他引:1       下载免费PDF全文
According to optimal foraging theory, animals should prefer food items with the highest ratios of energy intake to handling time. When single items have negligible handling times, one large item should be preferred to a collection of small ones of equivalent total weight. However, when pigeons were offered such a choice on equal concurrent variable-interval schedules in a shuttlebox, they preferred the side offering many small items per reinforcement to that offering one or a few relatively large items. This preference was still evident on concurrent fixed-cumulative-duration schedules in which choosing the alternative with longer handling time substantially lowered the rate of food intake.  相似文献   
970.
The present experiments studied a three-event delayed sequence-discrimination (DSD) task: one arrangement (order) of two stimuli (red and yellow overhead lights) taken three in succession (e.g., red, yellow, red) was the positive sequence and the remaining seven arrangements were the negative sequences for responding and reward during the subsequent test stimulus. In Experiment 1, the final stimulus (recency) and the order of stimuli in the positive sequence controlled acquisition of discrimination. In Experiment 2, increasing the duration of memory intervals between stimuli reduced the discriminability of those negative sequences identical to the positive sequence after the delay. Three-event DSD performance in Experiments 1 and 2 was similar to two-event DSD performance in comparable published experiments. Models developed to explain pigeon performance in two-event DSD were extended to the three-event task. Results from both two- and three-event versions of the DSD task falsified a noncumulative model and several cumulative integration models (i.e., adding, averging, and some multiplying models), but corroborated one cumulative, multiplying model.  相似文献   
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