Space-based visual attention models and object selection: Constraints,problems, and possible solutions

Summary One of the functions of visual attention is the selection of object information. This seems to be in line with an influential group of attentional models that assume that attentional selection is space based. These models assume that the selection of an object in vision is realized by selection of the location of that object. Whether this relatively simple idea of space-based attention and the corresponding, more elaborated space-based models are sufficient to handle selected constraints and problems of object selection is the main issue of this article. The first step toward an answer is to describe the common computational structure of space-based attentional models. Two model classes will be distinguished: capacity-limited models (e.g., Treisman, 1988; LaBerge & Brown, 1989) and models that do not assume a capacity limitation (e. g., Van der Heijden, 1992). Next, three kinds of task and data on object selection are introduced that are especially challenging for space-based models. The first type of data refers to experiments that require selection between overlapping objects. The second type of data concerns the influence of early perceptual grouping - a strong object-defining factor- on late response competition, and the third type consists of a selection task in which a high-level (semantic) attribute defines an object and controls selection. In all three cases, problems of space-based models are analyzed and possible solutions are sketched. Finally, a brief evaluative summary is given.     

Motor skill acquisition and retention as a function of average feedback, summary feedback, and performance variability

Summary feedback involves withholding feedback from subjects until the last trial in a block is completed, and then presenting feedback about each trial. A variation of this method, called average feedback (Young & Schmidt, 1992), presents subjects with only the mean of the trial block. We investigated whether these methods have similar effects on acquisition and retention of a simple motor skill. Five groups of subjects (n = 16 per group) performed 60 acquisition trials of an aiming task involving both spatial and temporal accuracy. We presented average and summary feedback based on either 5-trial blocks or 15-trial blocks and compared these schedules with every-trial feedback. During acquisition, all groups improved with practice, with a slight tendency for the every-trial condition to have less absolute error than the longer summary and average conditions. Analysis of delayed no-feedback retention tests, however, revealed a strong advantage for the 5-trial summary and average conditions compared with the every-trial condition. In addition, we found that for long blocks of acquisition trials without augmented feedback, the performance variability of those trials was associated with retention performance. Results are discussed in terms of how these different manipulations may make feedback less useful during acquisition, but foster the use of certain information processing activities that enhance overall learning.     

杏仁复合体损毁对大鼠空间认知能力的影响

杏仁复合体损毁大鼠Ｍｏｒｒｉｓ迷宫作业学习成绩显著低于控制组,记忆成绩较显著低于控制组。其搜索目标时主要采用与控制组的图式策略相异的趋向式策略。策略差异提示：杏仁复合体参与大鼠空间认知的辅助加工。     

教师评分用语词义赋值特征的分析

本研究运用模糊统计试验方法对教师的六组定性的评分用语词 (符号 )进行了经验赋值。参加赋值的是 2 66名小学教师。结果表明 ,六组评分用语词 (符号 )都是模糊概念 ,其中每种评分方式中处于最高等级的词 (符号 )的模糊度最小 ,处于中间等级的词 (符号 )的模糊度居中 ,处于最低等级的词 (符号 )的模糊度最大。词 (符号 )义的模糊度与评价的把握度呈现负相关 ,即词 (符号 )义越具体 ,模糊度越小 ,赋值的把握度就越大 ;反之 ,词义越含混 ,模糊度越大 ,赋值的把握度就越小。教师对各种评分用语词 (符号 )的赋值受百分制的“及格—不及格”的划分的影响 ,受评分方式中等级数目的影响 ,即增加评分等级会减少评分用语词 (符号 )的模糊度 ,增加赋值的把握度 ,还受评分用语词 (符号 )本身数量特征的影响。在各种评分方式中 ,评语词 (符号 )在心理量表上的距离是不等的。本研究的结果对教育评价的实践具有一定的参考价值。     

A revised list of Spanish translations of operant terminology

The experimental analysis of behavior has grown enormously in Latin America within the last decade. This paper offers an updating revision of suggested Spanish translations of operant expressions.     

Manual discrimination of force using active finger motion

In these experiments, two plates were grasped between the thumb and forefinger and squeezed together along a linear track. An electromechanical system presented a constant resistance force during the squeeze up to a predetermined location on the track, whereupon the force effectively went to infinity (simulating a wall) or to zero (simulating a cliff). The task of the subject was to discriminate between two alternative levels of the constant resistance force (a reference level and a reference-plus-increment level). Results of these experiments indicate a just noticeable difference of roughly 7% of the reference force using a one-interval paradigm with trial-by-trial feedback over the ranges 2.5≤F _o≤10.0 newtons, 5≤D≤30 mm, 45≤S≤125 mm, and 25≤V≤160 mm/sec, whereF _o is the reference force,D is the distance squeezed,S is the initial finger-span, andV is the mean velocity of the squeeze. These results, based on tests with 5 subjects, are consistent with a wide range of previous results, some of which are associated with other body surfaces and muscle systems and many of which were obtained with different psychophysical methods.     

Sexual experience, sex guilt, and sexual moral reasoning

Two studies are described in which the relations between sexual experience, sex guilt, and sexual moral reasoning were examined. Subjects were asked to articulate their opinions on each of six sexual activities, and then choose one of six statements (corresponding to Kohlberg's six stages of reasoning) that most clearly reflected why they had, or had not, engaged in three of those activities. An analysis of the moral reasoning present in each of the six articulated responses indicated that level of reasoning was inversely related to sex guilt. Analysis of the preference data indicated that subjects endorsed reasoning (statements) at a higher stage than they had articulated, and that this “gap” between articulation and preference was much greater for less experienced subjects. Results are discussed in terms of the utility of using situation-specific moral dilemmas when assessing moral reasoning, and in terms of the possible role that lack of sexual experience plays in inhibiting sexual moral development.