Correlations Between Input and Output Units in Neural Networks

Correlation analyses of recent back-propagation neural networks show that network results are due to imbalances in stimulus input. Conclusions concerning the effects of receptive field size, hemispheric specialization, and other issues of relevance to psychology cannot therefore be drawn until the dominating effects of low-level correlations are removed. Statistical techniques for evaluating the stimulus materials for neural networks are introduced.     

Differences in performance of young and old monkeys on a visuospatial memory task

Two groups of stumptailed macaques (Macaca arctoides) were compared in terms of performance on a visuospatial working memory task involving repeated presentations of an array of 15 doors, each of which concealed one food reward at the start of a session. Rewards obtained by the subject were not replaced. Errors were defined as responses to doors previously pushed open during the session. Both groups generally obtained all rewards and showed improved performance across sessions, but old monkeys consistently made more errors than young ones, especially in the latter half of a given session. Further, old monkeys were less diverse in the errors they made, indicating different response strategies by the two groups.     

第三世界的"毛主义"

用于描述亚洲、非洲和拉丁美洲的第三世界的观念随着第二次世界大战而产生.当美国领导的资本主义第一世界和苏联领导的社会主义第二世界在冷战中为争夺全球的统治地位而斗争时,第三世界常常成为战场或者军事行动的演出场所.