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961.
Joint presentations of a conditioned stimulus (CS) and an unconditioned stimulus (US) strengthen the contingency between them, whereas presentations of one stimulus without the other degrade this contingency. For example, the CS can be presented without the US either before conditioning (CS–no US and then CS–US; latent inhibition) or after conditioning (CS–US and then CS–no US; extinction). In vertebrate subjects and several invertebrate species, a time lapse usually results in a return of the conditioned response, or spontaneous recovery. However, in land mollusks, spontaneous recovery from extinction has only recently been reported, and response recovery after latent inhibition has not been reported. In two experiments, using conditioned aversion to a food odor as a measure of learning and memory retention, we observed contingency degradation via latent inhibition (Experiment 1) and extinction (Experiment 2) in the common garden slug, Lehmannia valentiana. In both situations, the contingency degradation procedure successfully attenuated conditioned responding, and delaying testing by several days resulted in recovery of the conditioned response. This suggests that the CS–US association survived the degradation manipulation and was retained over an interval of several days. 相似文献
962.
Kenneth J. Leising Jared Wong Chad M. Ruprecht Aaron P. Blaisdell 《Learning & behavior》2014,42(4):357-364
Many studies investigating cue competition have focused on the blocking effect. We investigated the blocking effect with pigeons using a landmark-based spatial search task in both a touchscreen preparation (Exp. 1a) and an automated remote environmental navigation apparatus (Exp. 1b). In Phase 1, two landmarks (LMs: A and Z) appeared on separate trials as colored circles among a row of eight (touchscreen) or six (ARENA) identical response units. Subjects were rewarded for pecking at a target response unit to the right of LM A and to the left of an extraneous LM, Z. During the blocking trials in Phase 2, LM X was presented in compound with a second LM (A) that had been previously trained. On control trials, LM Y was presented in compound with LM B and a target in the same manner as in the trials of AX, except that neither landmark had previously been trained with the target. All subjects were then tested with separate trials of A, X, B, and Y. Testing revealed poor spatial control by X relative to A and Y. We report the first evidence for a spatial-blocking effect in pigeons and additional support for associative effects (e.g., blocking) occurring under similar conditions (e.g., training sessions, spatial relationships, etc.) in 3-D and 2-D search tasks. 相似文献
963.
M. P. Biktimirov S. A. Polikarpov A. Yu. Scherbakov P. V. Efremov D. L. Solodkin 《Scientific and Technical Information Processing》2014,41(3):178-182
The main aspects related to the development of a system for the aggregation and use of scientific results (hereinafter, the System) are discussed. A unified comprehensive approach to the development of the System and the qualitative improvement of the information about the performance of the Russian research sector provided to the target audience is being suggested for use by academic institutions, government regulators, and the business community. The improvement is meant to be achieved through the development of technology that provides access to the relevant electronic resources. The presented conclusions lay the basis for a range of research and development works in the field related to the collection of scientific results. 相似文献
964.
Most extant research on end-of-life communication in families has been based on the assumption that more communication is better communication. We used a multiple goals theoretical perspective to demonstrate that the quality of communication about end-of-life decisions matters. Members of 121 older parent/adult child dyads (N = 242) engaged in an elicited conversation about end-of-life health choices and reported their assessments of the conversation. Using multilevel linear modeling, we found that outside ratings of a person's communication quality (i.e., attention to task, identity, and relational goals) as well as outside ratings of the partner's communication quality were positively associated with the person's reported conversational satisfaction and hopefulness and negatively associated with the person's hurt feelings and relational distancing. 相似文献
965.
Study on the Fuzzy COntrol Strategy of Automobile with CVT 总被引:3,自引:0,他引:3
In order to study the dynamic characteristics of automobile with a CVT system, a bond graph analysis model of continuously variable transmission is established.On the base of the simulation state space equations that are established with bond graph theory,a fuzzy control strategy with an expert system of starting process has been introduced.Considering uncertain system parameters and exterior resistance disturbing,the effect of the profile of membership function and the defuzzification algorthm on the capacity of the fuzzy controller has been studied.The result of simulation proves that the proposed fuzzy controller is effective and feasible,Such controller has been employed in the actual control and has proved practicable.The study lays a foundation for design of the fuzzy controller for automobile with a CVT system. 相似文献
966.
The subject of this work is the assessment on the stability of an excavated high slope in order to insure the security of the building site adjacent to the slope,which is frequently encountered in town construction in mountainous areas due to terrain limit.On the base of some typical engineering cases in Chongqing,several crucial problems on security assessment of building site adjacent to an excavated high slope,including the natural geological conditions and man-destroyed degree,engineering environment,potential failure pattern of the high slope,calculation parameters and analysis methods,are roundly discussed.It is demonstrated that the conclusion of security assessment can be determined according to the aspects above-mentioned,and the security assessment is one of the fundamental data to insure the safety of the related construction,site and buildings. 相似文献
967.
968.
对体操教学中的诱导练习的特点、类型以及对动作技能形成的影响进行了论述.教师可根据教学的目的任务、场地器材条件、学生身体技术素质等具体条件,灵活运用. 相似文献
969.
从“学生投入”的角度,对体育教学中普遍存在的学生外显的积极行为和内隐的消极心理这一矛盾进行深入分析,认为体育教学应该重视学生积极情感的投入,减少遵守规范式和消极情感式的情感投入;重视学生积极性的认知投入,减少表面性的认知投入;重视学生积极的行为投入,减少消极的行为投入。 相似文献
970.
优秀赛艇运动员血色素的分析 总被引:9,自引:0,他引:9
对湖北优秀赛艇运动员的血色素进行了分析。结果表明,数年的赛艇运动使他们的血色素约增加了12.3%。 相似文献