Conditional discrimination in mentally retarded subjects: programming acquisition and learning set.

In Experiment 1, 3 subjects with retardation were exposed to two visual-visual arbitrary matching-to-sample problems each day. One conditional discrimination was presented under trial-and-error conditions, and the other was presented under a component training procedure. The latter began by establishing the comparison discrimination and its rapid reversal. The successive discrimination between the sample stimuli was established through differential naming. Then, sample naming was maintained in conditional discrimination sessions in which the same sample was presented in blocks of consecutive trials. Block size was decreased across sessions until sample presentation was randomized as in trial-and-error training (but with naming maintained). Two subjects initially learned only with component training. The performance of the 3rd subject was inconsistent across conditional discriminations. One of the successful subjects ultimately learned rapidly and consistently with trial-and-error procedures. Experiment 2 sought to demonstrate learning set in the other 2 subjects. Elements of the component training procedure were withdrawn over successive conditional discriminations. Ultimately, 1 subject nearly always learned under trial-and-error conditions, and the other learned under trial-and-error conditions combined with differential sample naming.     

注意定势对基于空间位置的返回抑制的影响

将研究注意定势的比例控制范式与基于空间位置的返回抑制范式相结合。系统地探讨了与空间位置相关的注意定势对基于空间位置的返回抑制的影响。结果表明。在20％和50％有效条件下均出现了显著的返回抑制。但由于注意定势的作用。20％有效条件下的返回抑制量要明显高于50％有效条件;而在80％有效条件下．没有出现返回抑制。并且外显地形成相关注意定势的被试显示出显著的返回抑制的反转。而没有外显地形成相关注意定势的被试则显示出了返回抑制效应。这表明,内源性的注意定势对返回抑制的质和量都有重要影响。适当的注意定势可以在任意方向上改变返回抑制。     

A First Order Nonmonotonic Extension of Constructive Logic

Certain extensions of Nelson's constructive logic N with strong negation have recently become important in arti.cial intelligence and nonmonotonic reasoning, since they yield a logical foundation for answer set programming (ASP). In this paper we look at some extensions of Nelson's .rst-order logic as a basis for de.ning nonmonotonic inference relations that underlie the answer set programming semantics. The extensions we consider are those based on 2-element, here-and-there Kripke frames. In particular, we prove completeness for .rst-order here-and-there logics, and their minimal strong negation extensions, for both constant and varying domains. We choose the constant domain version, which we denote by QN^c₅, as a basis for de.ning a .rst-order nonmonotonic extension called equilibrium logic. We establish several metatheoretic properties of QN^c₅, including Skolem forms and Herbrand theorems and Interpolation, and show that the .rst-oder version of equilibrium logic can be used as a foundation for answer set inference.     

Weakly higher order cylindric algebras and finite axiomatization of the representables

We show that the variety of n-dimensional weakly higher order cylindric algebras, introduced in Németi [9], [8], is finitely axiomatizable when n > 2. Our result implies that in certain non-well-founded set theories the finitization problem of algebraic logic admits a positive solution; and it shows that this variety is a good candidate for being the cylindric algebra theoretic counterpart of Tarski’s quasi-projective relation algebras. Supported by the Hungarian National Foundation for Scientific Research grant T73601.     

Stereotype threat and inflexible perseverance in problem solving

The present research examines whether women burdened by stereotype threat, a threat of confirming negative ingroup stereotypes (Steele, C. M., & Aronson, J. (1995). Stereotype threat and the intellectual test performance of African Americans. Journal of Personality and Social Psychology, 69(5), 797-811), are less able to abandon old strategies and employ newer, more efficient ones when conditions change. In two studies, stereotype threat was found to increase inflexible perseverance: women made to believe they were taking a diagnostic math/spatial ability test, compared to those not threatened by stereotypes, were more likely to use previously successful but presently inefficient or incorrect strategies. In Study 1, participants under stereotype threat also suppressed relevant stereotypes to the greatest degree, and their inflexible perseverance was predicted by the degree to which they suppressed these stereotypes. Implications for test performance and potential decision-making effects of stereotype threat are discussed.     

Executive control of thought and action: in search of the wild homunculus

Executive control is studied in many areas of psychological research using a wide variety of procedures. This article focuses on studies of the executive processes involved in switching between tasks. The experiments discussed were designed to isolate and measure the duration of the executive processes required to switch from one task to another. However, the research is open to alternative interpretations that do not hypothesize executive processes, suggesting that task-switching procedures may not measure the duration of executive control. Further research is required to determine whether or not behavioral effects reflect the involvement of executive processes.     

注意定势及时间不确定性对基于空间的返回抑制的影响

在两个实验中使用比例控制范式 ,研究了基于空间位置的注意定势及时间不确定性对检测任务中IOR出现时程的影响。实验 1以 75名本科生为被试 ,将SOA水平作为组间变量 ,从而消除了时间不确定性。结果发现 ,当被试形成“更依赖于提示位置”的注意定势时 ,IOR出现的时程延长。实验 2以 2 2名本科生为被试 ,将SOA作为组内变量 ,从而将时间不确定性引入实验任务。结果表明 ,存在时间不确定性时 ,IOR出现的时程恢复到正常水平。两个实验的结果表明 ,IOR的时程受到内源和外源性注意之间交互作用的影响 ,而注意定势和时间不确定性是决定IOR何时出现及持续时间的两个十分关键的因素。     

Bets and Boundaries: Assigning Probabilities to Imprecisely Specified Events

Uncertainty and vagueness/imprecision are not the same: one can be certain about events described using vague predicates and about imprecisely specified events, just as one can be uncertain about precisely specified events. Exactly because of this, a question arises about how one ought to assign probabilities to imprecisely specified events in the case when no possible available evidence will eradicate the imprecision (because, say, of the limits of accuracy of a measuring device). Modelling imprecision by rough sets over an approximation space presents an especially tractable case to help get one’s bearings. Two solutions present themselves: the first takes as upper and lower probabilities of the event X the (exact) probabilities assigned X’s upper and lower rough-set approximations; the second, motivated both by formal considerations and by a simple betting argument, is to treat X’s rough-set approximation as a conditional event and assign to it a point-valued (conditional) probability. With rough sets over an approximation space we get a lot of good behaviour. For example, in the first construction mentioned the lower probabilities are n-monotone, for every . When we examine other models of approximation/imprecision/vagueness, and in particular, proximity spaces, we lose a lot of that good behaviour. In the literature there is not (even) agreement on the definition of upper and lower approximations for events (subsets) in the underlying domain. Betting considerations suggest one choice and, again, ways to assign upper and lower and point-valued probabilities, but nothing works well. Special Issue on Vagueness Edited by Rosanna Keefe and Libor Bêhounek     

Why good thoughts block better ones: the mechanism of the pernicious Einstellung (set) effect

The Einstellung (set) effect occurs when the first idea that comes to mind, triggered by familiar features of a problem, prevents a better solution being found. It has been shown to affect both people facing novel problems and experts within their field of expertise. We show that it works by influencing mechanisms that determine what information is attended to. Having found one solution, expert chess players reported that they were looking for a better one. But their eye movements showed that they continued to look at features of the problem related to the solution they had already thought of. The mechanism which allows the first schema activated by familiar aspects of a problem to control the subsequent direction of attention may contribute to a wide range of biases both in everyday and expert thought - from confirmation bias in hypothesis testing to the tendency of scientists to ignore results that do not fit their favoured theories.