导航线路和个体认知风格对超文本搜索绩效的影响

本研究考察了导航线路和个体认知风格对主题性问题搜索绩效的影响效应。实验采用 2× 3的被试间设计 ,自变量为导航线路和个体认知风格 ,因变量为被试回答每个相关问题所需要的平均时间、搜索过程中打开的平均节点数和重复节点数。结果表明 ,导航线路的主效应达到显著的水平 ,而认知风格的主效应和两者的交互作用没有显著性。结论认为 :采用“关键点线路”导航有利于超文本信息的搜索     

物体位置与空间关系的心理表征

外界环境中物体位置与空间关系在记忆中如何表征,一直是空间认知研究领域探讨和争论的热点问题。该文从空间表征的参照框架、朝向特异性、组织结构和存储内容四个方面,系统回顾了近年来对空间表征形成机制与内在特征的理论探讨。在此基础上,进一步讨论了当前空间表征研究中存在的生态效度问题,以及以后将虚拟环境技术引入到空间认知研究中的发展趋势     

Relative reinforcing effects of different oral ethanol doses in rhesus monkeys

The relative reinforcing effects of different doses of orally delivered ethanol were evaluated. Mouth-contact responding by rhesus monkeys was measured under concurrent fixed-ratio fixed-ratio schedules of liquid delivery (0.67 ml/delivery) from each of two spouts during daily 3-hr sessions. Experiment 1 examined persistence of responding with ethanol (2%, 8%, and 32% wt/vol) and water available. When fixed-ratio values from 8 to 128 were tested, the number of ethanol deliveries obtained per session decreased as the response requirement increased. The decrease in deliveries was less at higher than at lower ethanol concentrations, however. Experiment 2 examined choice between two ethanol concentrations under concurrent fixed-ratio 16 schedules (4% vs. 8%, 4% vs. 16%, 8% vs. 16%, 2% vs. 8%, 2% vs. 32%, 8% vs. 32%). Higher concentrations (16%, 32%) generally maintained more responding than concurrently available concentrations of 8% or less. An exception was the observation of a preference for 8% over 32% ethanol. When the fixed-ratio value was increased, however, the relative preference for these two doses was reversed so that 32% ethanol maintained more responding than 8% ethanol. Thus, the direction of the preference depended on the size of the response requirement. These results indicate that the reinforcing effects of ethanol increase with dose.