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61.
Reexamination of the role of the hypothalamus in motivation 总被引:3,自引:0,他引:3
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James R. Pomerantz Stephen Kaplan Rachel Kaplan 《Attention, perception & psychophysics》1969,6(3):129-132
When single letters were presented for five flashes, with S making a clarity judgment after each exposure, initial potentiation and subsequent satiation effects were found. A processing task and complete prior knowledge led to an increased probability of a “clear” response on the first exposure and to an earlier onset of the satiation effect. The results are discussed in terms of the neural network model underlying this research. 相似文献
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Most current commercial devices dispense dry food pellets by moving the pellets horizontally toward a discharge point. Individual pellets, captured by perforations in a horizontal metal disk, are discharged one by one by stepwise rotation of the disk within the pellet reservoir. In our laboratory, where the average pellet discharge rate is some 20,000 pellets per week, feeders of this type produced occasional problems. Some were electronic; others involved failure always to capture a pellet in each perforation, particularly when the pellet supply was low. But the most common problem was an accumulation of pellet chips and dust under and around the perforated disk, which ultimately jammed the mechanism. Despite weekly cleaning and maintenance, troubles arose at least twice a month, prompting a search for a simpler pellet-feeder design which would be more reliable and require less maintenance. The present pellet feeder employs a vertical rather than horizontal design principle. It has been used extensively in operant conditioning applications for more than a year. More than 200,000 pellets have been reliably discharged from a single feeder without a breakdown. No maintenance, other than a weekly cleaning of the discharge tube, has been required. 相似文献
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Stephen Arnold Weinstein 《Integrative psychological & behavioral science》1967,2(2):118-126
The effects of varying CO2 concentration, and intervals between CO2 presentations, were determined from the performance by five pigeons of a learned motor act which eliminates CO2 from the inspired air. The length of time from the onset of an externally-produced increase in inspired CO2 to the performance of the learned motor response terminating the CO2 presentation was inversely related to the CO2 concentration presented (3 per cent and 5 per cent) and directly related to the inter-trial interval (3 minutes and 1.5 minutes). Chemoreceptors on the ventrolateral surfaces of the medulla are postulated to be the initial site of stimulation in the chain of events leading to the behavioral bioregulation of inspired CO2 concentration. 相似文献
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Richard J. Phillips Brain Coe Eiichi Kono John Knapp Stephen Barrett Graham Wiseman Piers Eveleigh 《Applied cognitive psychology》1990,4(6):485-497
Graphic designers and an experimental psychologist worked together to improve the design of two map symbols which are frequently confused: the symbols for cuttings and embankments on topographic maps. The problem was analysed in terms of the function of the symbols and their likely cognitive representations. Tests were developed to evaluate alternative designs, including an intervisibility task which requirred users to visualize the landform from the symbols viewed in the context of a map. Tests were given to schoolchildren and to experienced map users in order to compare the standard symbols with five alternative designs. Children's performance was strongly affected by the symbols they used, but experienced users were much less affected. After some refinement of the symbols a further experiment demonstrated the superiority of a number of alternative designs over the existing symbols on a range of test: scores were almost double on the intervisibility task. The paper makes recommendations to cartographers and argues for greater consideration of the inexperienced map user in the design process. 相似文献
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