Saccade landing point selection and the competition account of pro- and antisaccade generation: the involvement of visual attention--a review

This paper presents a review and summary of experimental findings on the role of attention in the preparation of saccadic eye movements. The focus is on experiments where performance of prosaccades (saccades towards a suddenly appearing item) and antisaccades (saccades of equal amplitude in the direction opposite to where the target moved) is compared. Evidence suggests that these two opposite responses to the same stimulus event entail competition between neural pathways that generate reflexive movements to the target and neural mechanisms involved in inhibiting the reflex and generating a voluntary gaze shift in the opposite direction to the target appearance. Evidence for such a competition account is discussed in light of a large amount of experimental findings and the overall picture clearly indicates that this competition account has great explanatory power when data on saccadic reaction times and error rates are compared for the two types of saccade. The role of attention is also discussed in particular in light of the finding that the withdrawal of attention by a secondary task 200 to 500 ms before the saccade target appears, leads to speeded antisaccades (without a similar increase in error rates), showing that the results do not simply reflect a speed-accuracy trade-off. This result indicates that the tendency for "reflexive" prosaccades is diminished when attention is engaged in a different task. Furthermore, experiments are discussed that show that as the tendency for a reflexive prosaccade is weakened, antisaccades are speeded up, further supporting the competition account of pro- and antisaccade generation. In the light of evidence from neurophysiology of monkeys and humans, a tentative model of pro- and antisaccade generation is proposed.     

三校大学生竞争／合作策略取向的特点及影响因素

为研究大学生竞争／合作策略取向的特点及影响因素,采用”合作与竞争策略标度”量表对144名大学生进行测查,并从能力变量、期望变量及背景变量进一步研究其影响因素。结果表明大学生竞争策略均分值普遍显著高于合作策略均分值,提示学生更崇尚竞争策略;女生的竞争策略均分值明显高于男生分值,表现出策略取向的性别差异。通过相关分析和多元逐步回归分析,表明学习能力、总体能力与父母期望对学生的竞争策略取向有一定的预测性,而性别和母亲受教育程度可部分预测学生合作策略取向。     

Ambiguity in Our Technical Society

The spiritual situation at the turn of the millennium can be interpreted through Paul Tillich's appropriation of modernity, by analysis of the determinative structures and decisive trends of our age. The methods and organization of industry determine modern society. Spiritually, this situation results in the proliferation of means without ends, the objectification of natural structures, and the reduction of persons to things. Extrapolating from Tillich's analysis, the spiritual situation at the turn of the millennium can be understood as a quasi-religious struggle between the movements of liberal individualism and multiculturalism, both of which lose the sense of ambiguity. The communitarian movement and related interpretations remain the minority voice offering a mediating position.     

在校大学生捐精现状调查分析

了解在校大学生对捐精、精子库及供精人工授精后代的认知及其影响因素。对河南省4所高校在校学生发放“河南省在校大学生捐精认知调查问卷”进行调查，并进行统计学分析。结果显示，大多数学生知道捐精，但了解程度不够。男生、独生子女、医学生、城市学生对捐精知识的认知程度较高；影响捐精的主要因素为捐精知识的宣传程度、捐精对健康的影响等；担心个人隐私泄露、后代之间恋爱或结婚是在校大学生不支持捐精的主要原因。     

课堂情境中学生竞争对其成就归因和成就行为的影响

本研究把成就归因区分为倾向性成就归因和情境性成就归因两种类型,并分别检验了在课堂情境中学生之间的竞争对二者以及对成就行为的影响。被试是80名初中一年级学生。结果表明,(1)竞争对学生的倾向性成就归因没有明显影响,而显著地影响着学生的情境性成就归因;(2)竞争对学生随后成就行为没有明显影响;(3)倾向性成就归因对学生的成就行为的影响是显著的,但是它的这种影响却是间接发挥作用的。     

Effects of d-amphetamine, diazepam, and pentobarbital on the schedule-controlled pecking and locomotor activity of pigeons

Pigeons were trained on a variant of the autoshaping procedure devised by Matthews and Lerer (1987) in which a keylight stimulus ramp of increasing brightness signaled the passing of a 30-s interfood interval. This procedure generates two distinct behavioral components: key pecking and locomotor activity. The effects of three psychoactive drugs on these behavior classes were measured. d-Amphetamine had negligible effects on both types of behavior, whereas diazepam and pentobartital increased key pecking and decreased activity in a dose-dependent fashion. In Experiment 2, the possibility that drug effects were suppressed by excessively strong stimulus control exerted in Experiment 1 was tested by decreasing the discriminability of the stimulus ramp. The direction of the effects of diazepam and pentobarbital was the same as in Experiment 1 but the magnitude of the effects tended to be larger. The effects of d-amphetamine, however, remained quite small, suggesting that, under these conditions, locomotor activity and key pecking are less sensitive to d-amphetamine. In Experiments 3 and 4, key pecking was eliminated by removing the keylight. Reinforcers were presented at fixed intervals in Experiment 3 and at variable intervals in Experiment 4. The drug effects on activity observed in Experiments 1 and 2 disappeared in both Experiments 3 and 4. The results suggest that diazepam and pentobarbital affect activity indirectly by increasing key-pecking behavior, which, in turn, competitively decreases activity.     

Interpersonal contingencies: Performance differences and cost-effectiveness

Three reinforcement contingencies were compared with regard to performance differences and cost-effectiveness (i.e., responses per unit reinforcer). Pairs of college students were studied under individual, cooperative, or competitive contingencies using a concurrent setting that included one of these three contingencies as one alternative and a lower paying individual contingency as the other alternative. With the individual and the cooperative contingencies, overall response rates were typically high; under competitive contingencies the overall response rates were substantially lower. Subjects responded at very high rates when competing, but chose not to compete most of the time. Competition and cooperation produced the most cost-effective responding, assessed as the number of responses made per $.01 of reinforcer. High overall rates of competitive responding were obtained when the contests were longer and the lower paying alternative contingency was not available.     

Some parameters of behavioral contrast and allocation of interim behavior in rats

Two experiments examined the effects of baseline reinforcement rate and component duration on behavioral contrast and on re-allocation of interim behavior in rats. Positive behavioral contrast occurred during multiple variable-interval 10-second extinction (VI 10 EXT) after a multiple VI 10 VI 10 baseline condition, but not during multiple VI 60 EXT following multiple VI 60 VI 60 baseline. Component duration had no significant effect on contrast. These results differed from those found in studies of pigeons' key pecking. Contrast was accompanied by an increased rate of drinking in the changed component, but drinking in the constant component did not decrease. These results are not consistent with the competition theory of contrast, but are consistent with the predictions based on the matching law. However, no current theory seems to account for all instances of behavioral contrast.     

精子捐赠与伦理

引起男性不育的一个重要原因是无精症、死精症。精子捐赠的出现为这些患者带来了福音,使其享受天伦之乐成为可能,但同时也带来了一系列伦理学、社会学上的问题,包括子代的知情权问题、近亲结婚问题、家庭内部矛盾问题等等。因此要准确认识、运用和完善新的医学技术,并对其进行伦理和法律的规范,防止滥用。     

Enclosure shape influences cue competition effects and goal location learning

In virtual-environment spatial-learning procedures, Experiment 1 investigated blocking of learning about distal landmarks beyond the walls of an enclosure following preliminary training to find a goal using local landmarks within the enclosure. Separate sets of blocking and control groups searched within enclosures that, in plan view, formed either a square or a circle. Blocking was apparent when training and testing occurred in the circular but not the square enclosure. In Experiment 2, preliminary training to find a goal using local landmarks blocked spatial learning based on a circular enclosure divided into four differently coloured sections. The results are discussed in relation to theories of incidental versus error-correcting learning linked to different types of spatial cue.