Pigeons can discriminate locations presented in pictures

The present experiments were designed to teach pigeons to discriminate two locations represented by color photographs. Two sets of photographs were taken at two distinctive locations on a university campus. These sets represented several standpoints at each location. For the true-discrimination group, pictures from the two locations were differentially associated with reward; for the pseudodiscrimination group, half of the views from each location were arbitrarily but consistently associated with reward. The former group acquired the discrimination much more rapidly. These birds also showed good transfer to new views from the standpoints used in training and to a new standpoint at each location not used in training. In a second experiment, another group of pigeons could terminate any training trial by pecking an “advance” key. Three of 4 subjects used this option to reduce the duration of trials in which pictures from the negative location were presented. These data suggest that pigeons can integrate views shown in pictures into a “concept” of a location. The method used here may be the experimental analogue of a common, natural process by which animals learn to identify locations.     

On the limits of the matching concept in monkeys (Cebus apella).

Two cebus monkeys, with many years of experience matching a variety of static visual stimuli (forms and colors) within a standard matching-to-sample paradigm, were trained to press a left lever when a pair of displayed static stimuli were the same and to press a right lever when they were different. After learning the same/different task, the monkeys were tested for transfer to dynamic visual stimuli (flashing versus steady green disks), with which they had no previous experience. Both failed to transfer to the dynamic stimuli. A third monkey, also with massive past experience matching static visual stimuli, was tested for transfer to the dynamic stimuli within our standard matching paradigm, and it, too, failed. All 3 subjects were unable to reach a moderate acquisition criterion despite as many as 52 sessions of training with the dynamic stimuli. These results provide further evidence that, in monkeys, the matching (or identity) concept has a very limited reach; they consequently do not support the view held by some theorists that an abstract matching concept based on physical similarity is a general endowment of animals.     

Transfer of matching-to-figure samples in the pigeon

Three pigeons were trained on a modified six-key matching-to-sample procedure. The third peck on the figure-sample key (which presented a bird, hand, face, beetle, rabbit, fish, flower, or red hue, as the sample) lighted only one comparison key. Every three additional pecks on the sample lighted another comparison key, up to a maximum of five keys. Pecks on keys of matching figures produced grain. Pecks on nonmatching keys (mismatches) turned off all lights on the comparison keys and repeated the trial. Three figures were used during acquisition. The birds learned to peck each sample until the matching comparison stimulus appeared on one of three comparison stimulus keys, and then to peck that key. Later, five novel stimuli, employed as both sample and comparison stimuli, and two additional matching keys were added. Each bird showed matching transfer to the novel samples. The data suggest that the birds may have learned the concept of figure matching rather than a series of two-component chains or discrete five-key discriminations.     

Arguing about definitions

What are the implications of taking seriously Chaïm Perelman's proposition that “definitions are rhetorical”? Efforts to find Real Definitions are dysfunctional to the extent they direct argumentation toward pseudo “is” claims and away from explicit “ought” claims about how words are to be used. Addressing definitional disputes explicitly as propositions ofought rather thanis could put on the agenda the pragmatic concerns of definitional choice that might otherwise remain tacit.     

Category discrimination by pigeons using five polymorphous features

Eight pigeons were trained to discriminate between sets of color photographs of natural scenes. The scenes differed along five two-valued dimensions (site, weather, camera distance, camera orientation, and camera height), and all combinations of the feature values were used. One value of each dimension was designated as positive, and slides containing three or more positive feature values were members of the positive stimulus set. Thus, each feature had an equal, low, correlation with reinforcement, and all features had zero correlations with each other. Seven of the 8 pigeons learned this discrimination, and their responding came under the control of all five features. Within the positive and negative stimulus sets, response rates were higher to stimuli that contained more positive feature values. Once discrimination had been achieved, reversal training was given using a subset of the slides. In this subset, only a single feature was correlated with reinforcement. All pigeons learned this reversal successfully and generalized it to additional photographs with the same feature content. After reversal, the original reinforcement contingencies were reinstated, and training was continued using all the slides except those that had been used in reversal. Reversal generalized to these slides to some extent. Analysis of the response rates to individual slides showed that, compared with prereversal training, only the feature that had been subjected to reversal contingencies showed a reversed correlation with response rate. The remaining features showed the same correlation with response rate as they had before reversal training. Thus, reversal on some members of a category following category discrimination training led to generalization to stimuli within the category that were not involved in the reversal, but not to features that were not reversed. It is therefore inappropriate to refer to the pigeons as learning a concept.     

小学儿童合取概念的形成及其与元认知的关系

采用个别访谈与问卷相结合的方法．研究了小学四、五、六年级共48名儿童合取概念的形成及其元认知的发展。结果表明．小学儿童形成合取概念的能力发展既具有渐进性,又有不均衡性;其元认知知识水平和元认知监控能力的发展均呈现出稳中有变的趋势;各年级的元认知能力与形成合取概念的步数之间均存在非常显著的相关。     

Critical Rationalism in the Test Tube? Lecture given at the ’’International Summer School on the Philosophy of Chemistry and Biochemistry‘‘, Bradford & Ilkley Community College, 11. – 14. July 1994.

Popper's critical rationalism is widely accepted under scientists and philosophers of science as a proper method for the reconstruction of scientific theories. On occasion of the application of the Popperian ideas for the reconstruction of chemistry by Akeroyd the flaws of the critical rationalist approach are criticised and a methodical alternative is proposed, involving the operational definition of scientific terms. This revised version was published online in July 2006 with corrections to the Cover Date.     

Circular definitions,circular explanations,and infinite regresses

This paper discusses some of the ways in which circular definitions and circular explanations entail or fail to entail infinite regresses. And since not all infinite regresses are vicious, a few criteria of viciousness are examined in order to determine when the entailment of a regress refutes a circular definition or a circular explanation.I would like to thank Professors Robert Tully, Howard Sobel, and Derek Allen for their constructive comments.     

飞行错觉水平评定方法的初步研究

本文从飞行错觉发生的类型和频率出发,尝试对飞行员在实际飞行中所产生的错觉水平或空间定向能力做出基本的评定。本研究采用区间模糊统计的方法,对飞行错觉的类型（倾斜错觉、俯仰错觉、方位错觉、反旋转错觉和倒飞错觉）和频率（从无、偶尔、时有、经常、总是）做了经验的赋值工作,分别计算出了这些模糊概念（除从无外）的心理量表值和模糊度。同时我们认为,飞行错觉水平是频率与类型的函数,其数学表达式为：,并将这一表达式作为评定飞行员飞行错觉水平的基本模型。     

心理治疗中的脱落

脱落是指在心理咨询与治疗中, 来访者由于种种原因在导致他前来寻求帮助的心理困扰或问题尚未解决之前就终止治疗的现象。研究者对脱落概念内涵的理解比较一致, 但脱落的操作性定义存在多种且各有利弊。脱落在临床治疗中普遍存在; 脱落率在跨研究间的结果差异很大, 并受到脱落的操作性定义和研究设计类型的重要影响。传统的静态的变量在预测脱落时存在明显局限, 治疗同盟等治疗过程预测变量近年来得到更多重视, 并丰富了我们对来访者脱落的深入理解。为减少脱落, 研究者建议为来访者提供治疗前准备, 对治疗过程中的关键变量进行评估并根据具体情况采用合适的干预策略。未来研究需要完善脱落的操作性定义, 更多地在自然治疗设置下进行研究, 进一步深化脱落的预测变量研究, 并关注治疗外重要事件及文化背景对脱落的影响。