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141.
Despite its frequent use to assess effects of environmental and pharmacological variables on short-term memory, little is known about the development of delayed matching-to-sample (DMTS) performance. This study was designed to examine the dimensions and dynamics of DMTS performance development over a long period of exposure to provide a more secure foundation for assessing stability in future research. Six pigeons were exposed to a DMTS task with variable delays for 300 sessions (i.e., 18,000 total trials; 3,600 trials per retention interval). Percent-correct and log-d measures used to quantify the development of conditional stimulus control under the procedure generally and at each of five retention intervals (0, 2, 4, 8 and 16-s) individually revealed that high levels of accuracy developed relatively quickly under the shorter retention intervals, but increases in accuracy under the longer retention intervals sometimes were not observed until 100-150 sessions had passed, with some still increasing at Session 300. Analyses of errors suggested that retention intervals induced biases by shifting control from the sample stimulus to control by position, something that was predicted by observed response biases during initial training. These results suggest that although it may require a great deal of exposure to DMTS prior to obtaining asymptotic steady state, quantification of model parameters may help predict trends when extended exposure is not feasible. 相似文献
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讨论医院重点专科发展过程的阶段划分及特征,对于我们在重点专科建设中正确地把握方向、恰当地评估成效和有力地予以推进都有十分重大和现实的意义。本文把医院重点专科发展过程分为科室建设、学科建设、科学建设阶段,并从功能目标、效率效益、人才队伍、场地设施、技术设备、技术特色、教学培训、科学研究、文化氛围、能级水平十个方面对各阶段的特征进行归纳描述。三个阶段各具不同内涵特征,又存在相互内在关联,具有方向性、连续性、可加速性、交叉性和包涵性等规律。 相似文献
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We investigated how women’s hair color (blond, brown, black) and length (short, medium, long) influences males’ judgments about the women’s age, health, physical attractiveness, relationship potential, and parenting capability. Results, which are generally consistent with evolutionary psychology approaches, indicate that hair color and, to a lesser extent, length can affect perceptions of personal characteristics. More specifically, we found that lighter hair (blond and brown) compared to darker hair (black) is generally associated with perceptions of youth, health and attractiveness, and generally leads to more positive perceptions of relationship and parenting potential. Furthermore, the relationships between variables suggest that characteristics directly related to reproductive potential may be inferred from more obvious indirect characteristics. These results suggest that males are able to make complex judgments about women concerning their desirable relationship and parenting potential based on discernable characteristics such as hair color and length. 相似文献
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Melissa Swisher Peter J. Urcuioli 《Journal of the experimental analysis of behavior》2018,109(1):125-147
Until now, the equivalence property of reflexivity—matching physically identical stimuli to themselves after training on a set of arbitrary matching relations—has not been demonstrated in any animal, human or nonhuman. Previous reports of reflexivity have either implicitly or explicitly involved reinforced training on other identity matching relations. Here we demonstrate reflexivity without prior identity matching training. Pigeons received concurrent successive matching training on three arbitrary matching tasks: AB (hue–form), BC (form–hue), and AC (hue–hue with different hues in the A and C sets). Afterwards, pigeons were tested for BB (form–form) reflexivity. Consistent with the predictions of Urcuioli's ( 2008 ) theory, pigeons preferentially responded to B comparison stimuli that matched the preceding B sample stimuli in testing (i.e., BB reflexivity). A separate experiment showed that a slightly different set of arbitrary matching baseline relations yielded a theoretically predicted “anti‐reflexivity” (or emergent oddity) effect in two of five pigeons. Finally, training on just two arbitrary successive matching tasks (AB and BC) did not yield any differential BB responding in testing for five of eight pigeons, with two others showing reflexivity and one showing antireflexivity. These data complement previous findings of symmetry and transitivity (the two other properties of equivalence) in pigeons. 相似文献
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本研究设计了两种基于汉语全拼输入的提示性软键盘:加粗加黑和颜色提示,并通过实证性研究验证了这两种提示性软键盘对汉字输入绩效的影响。结果表明,两种提示性软键盘均优于非提示性软键盘,在打字速度、使用方便程度、喜爱程度和总体评价上均更好,加粗加黑提示性软键盘还显著提升了输入正确率。该结果为基于汉字输入的提示性软键盘的研发和使用提供了科学依据和数据支持,也将为相关键盘的投入市场做出贡献。 相似文献
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Mazur JE 《Journal of the experimental analysis of behavior》2006,86(2):211-222
Pigeons responded on concurrent-chains schedules with equal variable-interval schedules as initial links. One terminal link delivered a single reinforcer after a fixed delay, and the other terminal link delivered either three or five reinforcers, each preceded by a fixed delay. Some conditions included a postreinforcer delay after the single reinforcer to equate the total durations of the two terminal links, but other conditions did not include such a postreinforcer delay. With short initial links, preference for the single-reinforcer alternative decreased when a postreinforcer delay was present, but with long initial links, the postreinforcer delays had no significant effect on preference. In conditions with a postreinforcer delay, preference for the single-reinforcer alternative frequently switched from above 50% to below 50% as the initial links were lengthened. This pattern of results was consistent with delay-reduction theory (Squires & Fantino, 1971), but not with the contextual-choice model (Grace, 1994) or the hyperbolic value-added model (Mazur, 2001) as they have usually been applied. However, the hyperbolic value-added model could account for the results if its calculations were expanded to include reinforcers delivered in later terminal links. The implications of these findings for models of concurrent-chains performance are discussed. 相似文献